Search Results

Search found 19606 results on 785 pages for 'the thing'.

Page 515/785 | < Previous Page | 511 512 513 514 515 516 517 518 519 520 521 522  | Next Page >

  • Need help on a problemset in a programming contest

    - by topher
    I've attended a local programming contest on my country. The name of the contest is "ACM-ICPC Indonesia National Contest 2013". The contest has ended on 2013-10-13 15:00:00 (GMT +7) and I am still curious about one of the problems. You can find the original version of the problem here. Brief Problem Explanation: There are a set of "jobs" (tasks) that should be performed on several "servers" (computers). Each job should be executed strictly from start time Si to end time Ei Each server can only perform one task at a time. (The complicated thing goes here) It takes some time for a server to switch from one job to another. If a server finishes job Jx, then to start job Jy it will need an intermission time Tx,y after job Jx completes. This is the time required by the server to clean up job Jx and load job Jy. In other word, job Jy can be run after job Jx if and only if Ex + Tx,y = Sy. The problem is to compute the minimum number of servers needed to do all jobs. Example: For example, let there be 3 jobs S(1) = 3 and E(1) = 6 S(2) = 10 and E(2) = 15 S(3) = 16 and E(3) = 20 T(1,2) = 2, T(1,3) = 5 T(2,1) = 0, T(2,3) = 3 T(3,1) = 0, T(3,2) = 0 In this example, we need 2 servers: Server 1: J(1), J(2) Server 2: J(3) Sample Input: Short explanation: The first 3 is the number of test cases, following by number of jobs (the second 3 means that there are 3 jobs for case 1), then followed by Ei and Si, then the T matrix (sized equal with number of jobs). 3 3 3 6 10 15 16 20 0 2 5 0 0 3 0 0 0 4 8 10 4 7 12 15 1 4 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 4 8 10 4 7 12 15 1 4 0 50 50 50 50 0 50 50 50 50 0 50 50 50 50 0 Sample Output: Case #1: 2 Case #2: 1 Case #3: 4 Personal Comments: The time required can be represented as a graph matrix, so I'm supposing this as a directed acyclic graph problem. Methods I tried so far is brute force and greedy, but got Wrong Answer. (Unfortunately I don't have my code anymore) Could probably solved by dynamic programming too, but I'm not sure. I really have no clear idea on how to solve this problem. So a simple hint or insight will be very helpful to me.

    Read the article

  • How do I maintain a really poorly written code base?

    - by onlineapplab.com
    Recently I got hired to work on existing web application because of NDA I'm not at liberty to disclose any details but this application is working online in sort of a beta testing stage before official launch. We have a few hundred users right now but this number is supposed to significantly increase after official launch. The application is written in PHP (but it is irrelevant to my question) and is running on a dual xeon processor standalone server with severe performance problems. I have seen a lot of bad PHP code but this really sets new standards, especially knowing how much time and money was invested in developing it. it is as badly coded as possible there is PHP, HTML, SQL mixed together and code is repeated whenever it is necessary (especially SQL queries). there are not any functions used, not mentioning any OOP there are four versions of the app (desktop, iPhone, Android + other mobile) each version has pretty much the same functionality but was created by copying the whole code base, so now there are some differences between each version and it is really hard to maintain the database is really badly designed, which is causing severe performance problems also for fixing some errors in PHP code there is a lot of database triggers used which are updating data on SELECT and on INSERT so any testing is a nightmare Basically, any sin of a bad programming you can imagine is there for example it is not only possible to use SQL injections in literally every place but you can log into app if you use a login which doesn't exist and an empty password. The team which created this app is not working on it any more and there is an outsourced team which suggested that there are some problems but was never willing to deal with the elephant in the room partially because they've got a very comfortable contract and partially due to lack of skills (just my opinion). My job was supposed to be fixing some performance problems and extending existing functionality but first thing I was asked to do was a review of the existing code base. I've made my review and it was quite a shock for the management but my conclusions were after some time finally confirmed by other programmers. Management made it clear that it is not possible to start rewriting this app from scratch (which in my opinion should be done). We have to maintain its operable state and at the same time fix performance errors and extend the functionality. My question is, as I don't want just to patch the existing code, how to transform this into properly written app while keeping the existing code working at the same time? My plan is: Unify four existing versions into common code base (fixing only most obvious errors). Redesign db and use triggers to populate it with data (so data will be maintained in two formats at the same time) All new functionality will be written as separate project. Step by step transfer existing functionality into the new project After some time everything will be in the new project Some explanation about #2, right now it is practically impossible to make any updates in existing db any change requires reviewing whole code and making changes in many places. Is such plan feasible at all? Another solution is to walk away and leave the headache to someone else.

    Read the article

  • Many sources of movement in an entity system

    - by Sticky
    I'm fairly new to the idea of entity systems, having read a bunch of stuff (most usefully, this great blog and this answer). Though I'm having a little trouble understanding how something as simple as being able to manipualate the position of an object by an undefined number of sources. That is, I have my entity, which has a position component. I then have some event in the game which tells this entity to move a given distance, in a given time. These events can happen at any time, and will have different values for position and time. The result is that they'd be compounded together. In a traditional OO solution, I'd have some sort of MoveBy class, that contains the distance/time, and an array of those inside my game object class. Each frame, I'd iterate through all the MoveBy, and apply it to the position. If a MoveBy has reached its finish time, remove it from the array. With the entity system, I'm a little confused as how I should replicate this sort of behavior. If there were just one of these at a time, instead of being able to compound them together, it'd be fairly straightforward (I believe) and look something like this: PositionComponent containing x, y MoveByComponent containing x, y, time Entity which has both a PositionComponent and a MoveByComponent MoveBySystem that looks for an entity with both these components, and adds the value of MoveByComponent to the PositionComponent. When the time is reached, it removes the component from that entity. I'm a bit confused as to how I'd do the same thing with many move by's. My initial thoughts are that I would have: PositionComponent, MoveByComponent the same as above MoveByCollectionComponent which contains an array of MoveByComponents MoveByCollectionSystem that looks for an entity with a PositionComponent and a MoveByCollectionComponent, iterating through the MoveByComponents inside it, applying/removing as necessary. I guess this is a more general problem, of having many of the same component, and wanting a corresponding system to act on each one. My entities contain their components inside a hash of component type - component, so strictly have only 1 component of a particular type per entity. Is this the right way to be looking at this? Should an entity only ever have one component of a given type at all times?

    Read the article

  • Wrapping REST based Web Service

    - by PaulPerry
    I am designing a system that will be running online under Microsoft Windows Azure. One component is a REST based web service which will really be a wrapper (using proxy pattern) which calls the REST web services of a business partner, which has to do with BLOB storage (note: we are not using azure storage). The majority of the functionality will be taking a request, calling our partner web service, receiving the request and then passing that back to the client. There are a number of reasons for doing this, but one of the big ones is that we are going to support three clients: our desktop application (win and mac), mobile apps (iOS), and a web front end. Having a single API which we then send to our partner protects us if that partner ever changes. I want our service to support both JSON and XML for the data transfer format, JSON for web and probably XML for the desktop and mobile (we already have an XML parser in those products). Our partner also supports both of these formats. I was planning on using ASP.NET MVC 4 with the Web API. As I design this, the thing that concerns me is the static type checking of C#. What if the partner adds or removes elements from the data? We can probably defensively code for that, but I still feel some concern. Also, we have to do a fair amount of tedious coding, to setup our API and then to turn around and call our partner’s API. There probably is not much choice on it though. But, in the back of my mind I wonder if maybe a more dynamic language would be a better choice. I want to reach out and see if anybody has had to do this before, what technology solutions they have used to (I am not attached to this one, these days Azure can host other technologies), and if anybody who has done something like this can point out any issues that came up. Thanks! Researching the issue seems to only find solutions which focus on connecting a SOAP web service over a proxy server, and not what I am referring to here. Note: Cross posted (by suggestion) from http://stackoverflow.com/questions/11906802/wrapping-rest-based-web-service Thank you!

    Read the article

  • Managing accounts on a private website for a real-life community

    - by Smudge
    Hey Pro Webmasters, I'm looking at setting-up a walled-in website for a real-life community of people, and I was wondering if anyone has any experience with managing member accounts for this kind of thing. Some conditions that must be met: This community has a set list of real-life members, each of whom would be eligible for one account on the website. We don't expect or require that they all sign-up. It is purely opt-in, but we anticipate that many of them would be interested in the services we are setting up. Some of the community members emails are known, but some of them have fallen off the grid over the years, so ideally there would be a way for them to get back in touch with us through the public-facing side of the site. (And we'd want to manually verify the identity of anyone who does so). Their names are known, and for similar projects in the past we have assigned usernames derived from their real-life names. This time, however, we are open to other approaches, such as letting them specify their own username or getting rid of usernames entirely. The specific web technology we will use (e.g. Drupal, Joomla, etc) is not really our concern right now -- I am more interested in how this can be approached in the abstract. Our database already includes the full member roster, so we can email many of them generated links to a page where they can create an account. (And internally we can require that these accounts be paired with a known member). Should we have them specify their own usernames, or are we fine letting them use their registered email address to log-in? Are there any paradigms for walled-in community portals that help address security issues if, for example, one of their email accounts is compromised? We don't anticipate attempted break-ins being much of a threat, because nothing about this community is high-profile, but we do want to address security concerns. In addition, we want to make the sign-up process as painless for the members as possible, especially given the fact that we can't just make sign-ups open to anyone. I'm interested to hear your thoughts and suggestions! Thanks!

    Read the article

  • Dadaism and Agility

    - by alexhildyard
    We all have our little bugbears, and something that has given me particular pause over the years is the place of Agility in the software development life cycle. While I have seen it used successfully on both small and Enterprise-level projects, I have also seen many instances in which long-standing technical debt has also originated under its watch. Ironically the problem in such cases seems to me not that the practitioners in question have failed to follow due process (Test, Develop, Refactor -- a common "what" of Agile), but basically that they have missed the point (the "why" of Agile). It's probably a sign of my age that I'm much more interested in the "why" than the "what", since I feel that the latter falls out naturally from the former, but that this is not a reciprocal relationship.Consider Dadaism, precursor to the Surrealist movement in the early part of the twentieth century. Anyone could stand up and proclaim he or she was Dada; anyone could write cut-ups, or pull words out a hat, or produce gibberish on duelling typewriters under the inspiration of Dada. And all that took place at such performances was a manifestation of Dada, and all the artefacts that resulted were also Dada. Hence one commentator's engimatic observation that 'when one speaks of Dada, then one speaks of Dada. But when one does not speak of Dada, one still speaks of Dada.'What is Dada? Literally, Dada is what you say it is. But that's also missing the point. Dada is about erecting a framework within which utterances like this are valid; Dada is about preparing a stage for itself. Dadaism exemplifies the purity of a process-driven ideology -- in fact an ideology that is almost pure process, with nothing extraneous in the way of formal method, and while perhaps Agile delivery should not embrace the liberties of Dadaism too literally, some of the similarities nevertheless are salutary.Agile -- like Dada -- is an attitude; it is about *being* agile; it is not really about doing a specific set of things that are somehow *part* of being Agile. It is an abstract base rather than an implementation, a characteristic rather than a factor. It is the pragmatic response to the need for change in the face of partial information, ephemeral requirements and a healthy dose of systematic uncertainty. In practice this will usually mean repeatedly making the smallest useful changes to a system, recognising that systems evolve, and that all change carries risk. It will usually mean that instead of investing effort in future-proofing a system against a known technology roadmap, one instead invests one's energies in the daily repetition and incremental development of processes best designed to accommodate change quickly. But though it may mean these things in practice, it isn't actually *about* either of these things; it's about the mindset, the attitude that conceives of such responses as sensible solutions given the larger and ultimately unclassifiable thing that constitutes the development lifecycle of a specific project.

    Read the article

  • Motivating yourself to actually write the code after you've designed something

    - by dpb
    Does it happen only to me or is this familiar to you too? It's like this: You have to create something; a module, a feature, an entire application... whatever. It is something interesting that you have never done before, it is challenging. So you start to think how you are going to do it. You draw some sketches. You write some prototypes to test your ideas. You are putting different pieces together to get the complete view. You finally end up with a design that you like, something that is simple, clear to everybody, easy maintainable... you name it. You covered every base, you thought of everything. You know that you are going to have this class and that file and that database schema. Configure this here, adapt this other thingy there etc. But now, after everything is settled, you have to sit down and actually write the code for it. And is not challenging anymore.... Been there, done that! Writing the code now is just "formalities" and makes it look like re-iterating what you've just finished. At my previous job I sometimes got away with it because someone else did the coding based on my specifications, but at my new gig I'm in charge of the entire process so I have to do this too ('cause I get payed to do it). But I have a pet project I'm working on at home, after work and there is just me and no one is paying me to do it. I do the creative work and then when time comes to write it down I just don't feel like it (lets browse the web a little, see what's new on P.SE, on SO etc). I just want to move to the next challenging thing, and then to the next, and the next... Does this happen to you too? How do you deal with it? How do you convince yourself to go in and write the freaking code? I'll take any answer.

    Read the article

  • How do you automate a SharePoint 2010 deployment?

    - by Enrique Lima
    In the last couple of months SharePoint traffic (consulting, training and speaking) has picked up.  And with that also the requests for deployments.  There are good, great, bad and really bad things around this. But that is for another topic.  However part of the good and great has been the fact of organizations wanting to do a proof of concept deployment (even when WSS or MOSS has been deployed). We can go through a session (Microsoft has the SDPS concept, SharePoint Deployment Planning Services) of discovering what the customer wants to achieve from their investment in the platform and then also proceed to model the solution that would fit their needs.  But it should not stop there.  The next step should be a POC (as many have requested) to test out. Now, on to the meat of this post.  How do I deploy?  While it is a good process to watch and see all of it take place, not many have the time to sit through that.  Even more so, when that has been part of the description of deploying the platform in the sessions mentioned above. I will, though, break it into a deployment for development purposes and a deployment of a farm. Two tools (or scripts) for those two different types of deployment. First, let me address the development environment.  Around the last week in October, Chris Johnson (SharePoint Product Team) announced a SharePoint Easy Setup for Developers.  The kit itself will assist you in installing SharePoint Server (in standalone mode), the tools that go around Visual Studio, Expression Studio and the Office 2010 tools. Here is the link to Chris’ post: http://blogs.msdn.com/b/cjohnson/archive/2010/10/28/announcing-sharepoint-easy-setup-for-developers.aspx The other scenario is the use of a script in assisting you through the deployment of a farm. Now, this is not to override planning.  It should highlight the need for planning even more.  How?  Having your service accounts planned, the structure of the sites and the scale of your deployment.  Enter AutoSPInstaller.  This is a CodePlex project, and the intent behind this is not only to automate the installation but to give some meaning and get some sense out of what goes on during a SharePoint deployment. How?  Take for example the creation of the databases, when we do the initial OOB deployment by using the wizard, more times than not, we leave the names as they are.  How is that a “bad thing”?  Let’s make it a better practice to rename those Databases, and have them take on a name that is not “GUID-ized”. Having a better naming convention will not hurt, on the other hand will allow for consistency. Here is the link to AutoSPInstaller’s site on CodePlex: http://autospinstaller.codeplex.com/

    Read the article

  • How to keep a data structure synchronized over a network?

    - by David Gouveia
    Context In the game I'm working on (a sort of a point and click graphic adventure), pretty much everything that happens in the game world is controlled by an action manager that is structured a bit like: So for instance if the result of examining an object should make the character say hello, walk a bit and then sit down, I simply spawn the following code: var actionGroup = actionManager.CreateGroup(); actionGroup.Add(new TalkAction("Guybrush", "Hello there!"); actionGroup.Add(new WalkAction("Guybrush", new Vector2(300, 300)); actionGroup.Add(new SetAnimationAction("Guybrush", "Sit")); This creates a new action group (an entire line in the image above) and adds it to the manager. All of the groups are executed in parallel, but actions within each group are chained together so that the second one only starts after the first one finishes. When the last action in a group finishes, the group is destroyed. Problem Now I need to replicate this information across a network, so that in a multiplayer session, all players see the same thing. Serializing the individual actions is not the problem. But I'm an absolute beginner when it comes to networking and I have a few questions. I think for the sake of simplicity in this discussion we can abstract the action manager component to being simply: var actionManager = new List<List<string>>(); How should I proceed to keep the contents of the above data structure syncronized between all players? Besides the core question, I'm also having a few other concerns related to it (i.e. all possible implications of the same problem above): If I use a server/client architecture (with one of the players acting as both a server and a client), and one of the clients has spawned a group of actions, should he add them directly to the manager, or only send a request to the server, which in turn will order every client to add that group? What about packet losses and the like? The game is deterministic, but I'm thinking that any discrepancy in the sequence of actions executed in a client could lead to inconsistent states of the world. How do I safeguard against that sort of problem? What if I add too many actions at once, won't that cause problems for the connection? Any way to alleviate that?

    Read the article

  • Simple rendering produces minor stutter

    - by Ben
    For some reason, this game loop renders the movement of a simple rectangle with no stuttering. double currTime; double prevTime = System.nanoTime() / NANO_TO_SEC; double FPSTIMER = System.nanoTime(); double maxTimeDiff = 100.0 / 1000.0; double delta = 1.0 / 60.0; int processes = 0, frames = 0; while(true){ currTime = System.nanoTime() / NANO_TO_SEC; if(currTime - prevTime > maxTimeDiff) prevTime = currTime; if(currTime >= prevTime){ process(); processes++; prevTime += delta; if(currTime < prevTime){ render(); frames++; } } else{ try{ Thread.sleep((long) (1000 * (prevTime - currTime))); } catch(Exception e){} } if(System.nanoTime() - FPSTIMER > 1000000000.0){ System.out.println("Process: " + (1000 / processes) + "ms FPS: " + (1000 / frames) + "ms"); processes = frames = 0; FPSTIMER += 1000000000.0; } } But for this game loop, I get really minor stuttering where the movement does not look smooth. long prevTime = System.currentTimeMillis(); long prevRenderTime = 0; long currRenderTime = 0; long delta = 0; long msPerTick = 1000 / 60; int frames = 0; int ticks = 0; double FPSTIMER = System.currentTimeMillis(); while (true){ long currTime = System.currentTimeMillis(); delta += (currTime - prevTime) / msPerTick; prevTime = currTime; while (delta >= 1){ ticks++; process(); delta -= 1; } prevRenderTime = System.currentTimeMillis(); render(); frames++; currRenderTime = System.currentTimeMillis(); try{ Thread.sleep((long) ((1000 / FPS) - (currRenderTime - prevRenderTime))); } catch(Exception e){} if(System.currentTimeMillis() - FPSTIMER > 1000.0){ System.out.println("Process: " + (1000.0 / ticks) + "ms FPS: " + (1000.0 / frames) + "ms"); ticks = frames = 0; FPSTIMER += 1000.0; } Is there any critical difference that I'm missing here? The one thing I noticed is that if I uncap the fps for the second game loop, the stuttering goes away. It doesn't make sense to me. Also, the second game loop came from Notch's Minicraft code with just my thread sleeping code added in.

    Read the article

  • Multiplayer tile based movement synchronization

    - by Mars
    I have to synchronize the movement of multiple players over the Internet, and I'm trying to figure out the safest way to do that. The game is tile based, you can only move in 4 directions, and every move moves the sprite 32px (over time of course). Now, if I would simply send this move action to the server, which would broadcast it to all players, while the walk key is kept being pressed down, to keep walking, I have to take this next command, send it to the server, and to all clients, in time, or the movement won't be smooth anymore. I saw this in other games, and it can get ugly pretty quick, even without lag. So I'm wondering if this is even a viable option. This seems like a very good method for single player though, since it's easy, straight forward (, just take the next movement action in time and add it to a list), and you can easily add mouse movement (clicking on some tile), to add a path to a queue, that's walked along. The other thing that came to my mind was sending the information that someone started moving in some direction, and again once he stopped or changed the direction, together with the position, so that the sprite will appear at the correct position, or rather so that the position can be fixed if it's wrong. This should (hopefully) only make problems if someone really is lagging, in which case it's to be expected. For this to work out I'd need some kind of queue though, where incoming direction changes and stuff are saved, so the sprite knows where to go, after the current movement to the next tile is finished. This could actually work, but kinda sounds overcomplicated. Although it might be the only way to do this, without risk of stuttering. If a stop or direction change is received on the client side it's saved in a queue and the char keeps moving to the specified coordinates, before stopping or changing direction. If the new command comes in too late there'll be stuttering as well of course... I'm having a hard time deciding for a method, and I couldn't really find any examples for this yet. My main problem is keeping the tile movement smooth, which is why other topics regarding synchronization of pixel based movement aren't helping too much. What is the "standard" way to do this?

    Read the article

  • root issues in softwarecenter, synaptic and update manager

    - by user188977
    i have a notebook samsung ativ 2 and ubuntu 12.04 precise, cinnamon desktop. after logging in today my update manager, synaptic and ubuntu softwarecenter stopped working. synaptic i can only launch from terminal the others from panel.when choosing to update, nothing happens. same thing when trying to install programms from syn. or softw.center.when launching softwarec. from terminal i get: marcus@ddddddddd:~$ software-center 2013-11-10 22:30:46,206 - softwarecenter.ui.gtk3.app - INFO - setting up proxy 'None' 2013-11-10 22:30:46,217 - softwarecenter.db.database - INFO - open() database: path=None use_axi=True use_agent=True (software-center:4772): Gtk-WARNING **: Theme parsing error: softwarecenter.css:34:20: Not using units is deprecated. Assuming 'px'. (software-center:4772): Gtk-WARNING **: Theme parsing error: softwarecenter.css:34:22: Not using units is deprecated. Assuming 'px'. (software-center:4772): Gtk-WARNING **: Theme parsing error: softwarecenter.css:56:20: Not using units is deprecated. Assuming 'px'. (software-center:4772): Gtk-WARNING **: Theme parsing error: softwarecenter.css:56:22: Not using units is deprecated. Assuming 'px'. (software-center:4772): Gtk-WARNING **: Theme parsing error: softwarecenter.css:60:20: Not using units is deprecated. Assuming 'px'. (software-center:4772): Gtk-WARNING **: Theme parsing error: softwarecenter.css:60:22: Not using units is deprecated. Assuming 'px'. 2013-11-10 22:30:46,977 - softwarecenter.backend.reviews - WARNING - Could not get usefulness from server, no username in config file 2013-11-10 22:30:47,320 - softwarecenter.ui.gtk3.app - INFO - show_available_packages: search_text is '', app is None. 2013-11-10 22:30:48,057 - softwarecenter.db.pkginfo_impl.aptcache - INFO - aptcache.open() 2013-11-10 22:31:00,646 - softwarecenter.fixme - WARNING - logs to the root logger: '('/usr/share/software-center/softwarecenter/utils.py', 201, 'get_title_from_html')' 2013-11-10 22:31:00,645 - root - WARNING - failed to parse: '<div style="background-color: #161513; width:1680px; height:200px;">  <div style="background: url('/site_media/exhibits/2013/09/AAMFP_Leaderboard_700x200_1.jpg') top left no-repeat; width:700px; height:200px;"></div> </div>' ('ascii' codec can't encode character u'\xa0' in position 70: ordinal not in range(128)) 2013-11-10 22:31:02,268 - softwarecenter.db.update - INFO - skipping region restricted app: 'Comentarios Web' (not whitelisted) 2013-11-10 22:31:02,769 - softwarecenter.db.update - INFO - skipping region restricted app: 'reEarCandy' (not whitelisted) 2013-11-10 22:31:04,821 - softwarecenter.db.update - INFO - skipping region restricted app: 'Flaggame' (not whitelisted) 2013-11-10 22:31:05,622 - softwarecenter.db.update - INFO - skipping region restricted app: 'Bulleti d'esquerra de Calonge i Sant Antoni ' (not whitelisted) 2013-11-10 22:31:08,352 - softwarecenter.ui.gtk3.app - INFO - software-center-agent finished with status 0 2013-11-10 22:31:08,353 - softwarecenter.db.database - INFO - reopen() database 2013-11-10 22:31:08,353 - softwarecenter.db.database - INFO - open() database: path=None use_axi=True use_agent=True 2013-11-10 22:33:32,319 - softwarecenter.backend - WARNING - _on_trans_error: org.freedesktop.PolicyKit.Error.Failed: ('system-bus-name', {'name': ':1.72'}): org.debian.apt.install-or-remove-packages 2013-11-10 22:36:01,818 - softwarecenter.backend - WARNING - daemon dies, ignoring: <AptTransaction object at 0x48e4b40 (aptdaemon+client+AptTransaction at 0x645aaa0)> exit-failed 2013-11-10 22:36:01,820 - softwarecenter.db.pkginfo_impl.aptcache - INFO - aptcache.open()

    Read the article

  • SQL Azure Security: DoS Part II

    - by Herve Roggero
    Ah!  When you shoot yourself in the foot... a few times... it hurts! That's what I did on Sunday, to learn more about the behavior of the SQL Azure Denial Of Service prevention feature. This article is a short follow up to my last post on this feature. In this post, I will outline some of the lessons learned that were the result of testing the behavior of SQL Azure from two machines. From the standpoint of SQL Azure, they look like one machine since they are behind a NAT. All logins affected The first thing to note is that all the logins are affected. If you lock yourself out to a specific database, none of the logins will work on that database. In fact the database size becomes "--" in the SQL Azure Portal.   Less than 100 sessions I was able to see 50+ sessions being made in SQL Azure (by looking at sys.dm_exec_sessions) before being locked out. The the DoS feature appears to be triggered in part by the number of open sessions. I could not determine if the lockout is triggered by the speed at which connection requests are made however.   Other Databases Unaffected This was interesting... the DoS feature works at the database level. Other databases were available for me to use.   Just Wait Initially I thought that going through SQL Azure and connecting from there would reset the database and allow me to connect again. Unfortunately this doesn't seem to be the case. You will have to wait. And the more you lock yourself out, the more you will have to wait... The first time the database became available again within 30 seconds or so; the second time within 2-3 minutes and the third time... within 2-3 hours...   Successful Logins The DoS feature appears to engage only for valid logins. If you have a login failure, it doesn't seem to count. I ran a test with over 100 login failures without being locked.

    Read the article

  • Generate MERGE statements from a table

    - by Bill Graziano
    We have a requirement to build a test environment where certain tables get reset from production every night.  These are mainly lookup tables.  I played around with all kinds of fancy solutions and finally settled on a series of MERGE statements.  And being lazy I didn’t want to write them myself.  The stored procedure below will generate a MERGE statement for the table you pass it.  If you have identity values it populates those properly.  You need to have primary keys on the table for the joins to be generated properly.  The only thing hard coded is the source database.  You’ll need to update that for your environment.  We actually used a linked server in our situation. CREATE PROC dba_GenerateMergeStatement (@table NVARCHAR(128) )ASset nocount on; declare @return int;PRINT '-- ' + @table + ' -------------------------------------------------------------'--PRINT 'SET NOCOUNT ON;--'-- Set the identity insert on for tables with identitiesselect @return = objectproperty(object_id(@table), 'TableHasIdentity')if @return = 1 PRINT 'SET IDENTITY_INSERT [dbo].[' + @table + '] ON; 'declare @sql varchar(max) = ''declare @list varchar(max) = '';SELECT @list = @list + [name] +', 'from sys.columnswhere object_id = object_id(@table)SELECT @list = @list + [name] +', 'from sys.columnswhere object_id = object_id(@table)SELECT @list = @list + 's.' + [name] +', 'from sys.columnswhere object_id = object_id(@table)-- --------------------------------------------------------------------------------PRINT 'MERGE [dbo].[' + @table + '] AS t'PRINT 'USING (SELECT * FROM [source_database].[dbo].[' + @table + ']) as s'-- Get the join columns ----------------------------------------------------------SET @list = ''select @list = @list + 't.[' + c.COLUMN_NAME + '] = s.[' + c.COLUMN_NAME + '] AND 'from INFORMATION_SCHEMA.TABLE_CONSTRAINTS pk , INFORMATION_SCHEMA.KEY_COLUMN_USAGE cwhere pk.TABLE_NAME = @tableand CONSTRAINT_TYPE = 'PRIMARY KEY'and c.TABLE_NAME = pk.TABLE_NAMEand c.CONSTRAINT_NAME = pk.CONSTRAINT_NAMESELECT @list = LEFT(@list, LEN(@list) -3)PRINT 'ON ( ' + @list + ')'-- WHEN MATCHED ------------------------------------------------------------------PRINT 'WHEN MATCHED THEN UPDATE SET'SELECT @list = '';SELECT @list = @list + ' [' + [name] + '] = s.[' + [name] +'],'from sys.columnswhere object_id = object_id(@table)-- don't update primary keysand [name] NOT IN (SELECT [column_name] from INFORMATION_SCHEMA.TABLE_CONSTRAINTS pk , INFORMATION_SCHEMA.KEY_COLUMN_USAGE c where pk.TABLE_NAME = @table and CONSTRAINT_TYPE = 'PRIMARY KEY' and c.TABLE_NAME = pk.TABLE_NAME and c.CONSTRAINT_NAME = pk.CONSTRAINT_NAME)-- and don't update identity columnsand columnproperty(object_id(@table), [name], 'IsIdentity ') = 0 --print @list PRINT left(@list, len(@list) -3 )-- WHEN NOT MATCHED BY TARGET ------------------------------------------------PRINT ' WHEN NOT MATCHED BY TARGET THEN';-- Get the insert listSET @list = ''SELECT @list = @list + '[' + [name] +'], 'from sys.columnswhere object_id = object_id(@table)SELECT @list = LEFT(@list, LEN(@list) - 1)PRINT ' INSERT(' + @list + ')'-- get the values listSET @list = ''SELECT @list = @list + 's.[' +[name] +'], 'from sys.columnswhere object_id = object_id(@table)SELECT @list = LEFT(@list, LEN(@list) - 1)PRINT ' VALUES(' + @list + ')'-- WHEN NOT MATCHED BY SOURCEprint 'WHEN NOT MATCHED BY SOURCE THEN DELETE; 'PRINT ''PRINT 'PRINT ''' + @table + ': '' + CAST(@@ROWCOUNT AS VARCHAR(100));';PRINT ''-- Set the identity insert OFF for tables with identitiesselect @return = objectproperty(object_id(@table), 'TableHasIdentity')if @return = 1 PRINT 'SET IDENTITY_INSERT [dbo].[' + @table + '] OFF; 'PRINT ''PRINT 'GO'PRINT '';

    Read the article

  • What to do when opensource project starts to tear apart? (or a manager tries to write code and than shouts at the team)

    - by Kabumbus
    Imagine there is an open source cross-platform project on Google code. It has lots of revisions (1000). It concentrates in itself lots technological stuff - rare stuff - it mixes top tech. It contains server, and more than one client. The project was created by a well-connected team of developers (friends) and a manager that was sponsoring project at its start up during its first few months (project now is more than a year old-sponsoring oss project is a big good deal- also gave the idea of project to developers). The project was growing in complexity and effort reqiered to continue development. Once upon a time a manager - team leader started trying to write code (he was a programmer in some other projects - not the best, but he felt like he was one). He started because one of the developers suggested an idea at the team meeting and he felt he just needed to do it on his own. He failed, and he told the dev team about it. The dev team did what he failed to do in a few days. After that, the manager feels that team codes with out him perfectly and gets the job done in short time. He felt sorry and lost and he started to crash like an old bad PC. Firstly, he started to scream (in forms of messages not in voice) he tried to tell developers that what they were doing was a bad, not-needed thing - developers kindly told him that his "beginnings" were not compilable while dev team product worked as needed. He told the developers that all work they do should be firstly discussed with him. Here is the part where we need to mention that all team members are "project owners" and logically have equal rights. The team leader suggested to the developers these options: change their dev process to go through him, or be moved from project owners to contributers. So what are our options as developers? What arguments we can provide to the team leader/manager for him to calm down? Is it possible to save the project or is it better to fork out now? An important issue is that lately we had no active ticket system, and I personally think that this was the reason the mess appeared. So... any ideas?

    Read the article

  • What is SOA ?

    - by llaszews
    First, let’s mention what SOA is not: • SOA is not the same thing as web services. Web Services implies the use of standard such as Java/JAX-RPC, .NET or REST. Web Services also implies the use of a WSDL, SOAP, and/or J2EE Connector Architecture (J2EE CA) and HTTP. SOA architectures can be implemented using J2EE CA, XML file transfer or Remote Procedural Call (RPC) over File Transfer Protocol (FTP), TCP/IP, Remote Method Invocation (RMI) or other protocols. In other words, Web Services are a very specific set of technologies. SOA is a concept and can be implemented in many different ways. Some very rudimentary, such as transfering flat files between applications. • SOA will not solve all of your problems. It will make your business more agile, increase business visibility, reduce integration costs and provide better reuse. However, if you don’t need help in these area or expect SOA to cure all of your IT problems, you are looking in the wrong place. • The concepts behind SOA are not new, but SOA is also not mature. SOA as it stands today has really only been around for 5 years. The concepts of standards based protocol handlers, predefined communication schemas and remote method invocation have been around for decades. So, what is SOA? SOA is an architectural blueprint, a way of developing applications, and a set of best practices. SOA is not an ‘out of the box’ solution you buy, install and then have up and running in a matter of months. SOA is a journey to a better way of doing business and the technology architecture to support this better way of doing business. SOA is also a broader set of technologies including more then just web services. Techologies like an Enterpirse Service Bus (ESB), Business Processs Execution Language (BPEL), message queues and Business Activity Monitoring (BAM) all are part of a SOA architecture. So, what is SOA? SOA is an architectural blueprint, a way of developing applications, and a set of best practices. SOA is not an ‘out of the box’ solution you buy, install and then have up and running in a matter of months. SOA is a journey to a better way of doing business and the technology architecture to support this better way of doing business. SOA is also a broader set of technologies including more then just web services. Techologies like an Enterpirse Service Bus (ESB), Business Processs Execution Language (BPEL), message queues and Business Activity Monitoring (BAM) all are part of a SOA architecture. Read more here: Oracle Modernization Solutions

    Read the article

  • Ubuntu 11.10 crashes all browsers often

    - by murat
    I have been using ubuntu 11.10 for 1 year,today it made me surprised. When I open google chrome it just closes itself. Firstly i thought that it is just for chrome and tried Firefox : It also closes itself and one thing more : I tried desktop programs such as image viewer it also closes itself.I restarted it but there is no changing.What can do this ? is it virus or another system problem ? I did not have any problem like this until today.. $ google-chrome (google-chrome:7064): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (google-chrome:7064): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (google-chrome:7064): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (google-chrome:7064): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", --2012-04-04 19:33:14-- https://clients2.google.com/cr/report Resolving clients2.google.com... 173.194.70.100, 173.194.70.101, 173.194.70.102, ... Connecting to clients2.google.com|173.194.70.100|:443... connected. HTTP request sent, awaiting response... 200 OK Length: unspecified [text/html] 2012-04-04 19:33:19 (888 KB/s) - `/dev/fd/3' saved [16] (exe:7166): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (exe:7166): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (exe:7166): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (exe:7166): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", Moonlight: 3.99.0.3 Moonlight: Attempting to load libmoonloaderxpi (exe:7201): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (exe:7201): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (exe:7201): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", (exe:7201): Gtk-WARNING **: Unable to locate theme engine in module_path: "pixmap", Failed to open VDPAU backend libvdpau_nvidia.so: cannot open shared object file: No such file or directory Segmentation fault After trying to install libvdpau1 error is changed : google-chrome --2012-04-04 20:05:03-- https://clients2.google.com/cr/report Resolving clients2.google.com... 173.194.70.113, 173.194.70.138, 173.194.70.139, ... Connecting to clients2.google.com|173.194.70.113|:443... connected. HTTP request sent, awaiting response... Moonlight: 3.99.0.3 Moonlight: Attempting to load libmoonloaderxpi 200 OK Length: unspecified [text/html] Saving to: `/dev/fd/3' [<=> ] 0 --.-K/s f4c55117d1b4656e [ <= ] 16 --.-K/s in 0s 2012-04-04 20:05:12 (337 KB/s) - `/dev/fd/3' saved [16] Segmentation fault

    Read the article

  • Help with Strategy-game AI

    - by f20k
    Hi, I am developing a strategy-game AI (think: Final Fantasy Tactics), and I am having trouble coming up for the design of the AI. My main problem is determining which is the optimal thing for it to do. First let me describe the priority of what action I would like the AI to take: Kill nearest player unit Fulfill primary directive (kill all player units, kill target unit, survive for x turns) Heal ally unit / cast buffer Now the AI can do the following in its turn: Move - {Attack / Ability / Item} (either attack or ability or item) {Attack / Ability / Item} - Move Move closer (if targets not in range) {Attack / Ability / Item} (if move not available) Notes Abilities have various ranges / effects / costs / effects. Each ai unit has maybe 5-10 abilities to choose from. The AI will prioritize killing over safety unless its directive is to survive for x turns. It also doesn't care about ability cost much. While a player may want to save a big spell for later, the AI will most likely use it asap. Movement is on a (hex) grid num of player units: 3-6 num of ai units: 3-7 or more. Probably max 10. AI and player take turns controlling ONE unit, instead of all at the same time. Platform is Android (if program doesnt respond after some time, there will be a popup saying to Force Quit or Wait - which looks really bad!). Now comes the questions: The best ability to use would obviously be the one that hits the most targets for the most damage. But since each ability has different ranges, I won't know if they are in range without exploring each possible place I can move to. One solution would be to go through each possible places to move to, determine the optimal attack at that location - which gives me a list of optimal moves for each location. Then choose the optimal out of the list and execute it. But this will take a lot of CPU time. Is there a better solution? My current idea is to move as close as possible towards the closest, largest group of people, and determine the optimal attack/ability from there. I think this would be a lot less work for the CPU and still allow for wide-range attacks. Its sub-optimal but the AI will still seem 'smart'. Other notes/questions: Am I over-thinking/over-complicating it? Better solution? I am open to all sorts of suggestions I have taken a look at the spell-casting question, but it doesn't take into account the movement - so perhaps use that algo for each possible move location? The top answer mentioned it wasn't great for area-of-effect and group fights - so maybe requires more tweaking? Please, if you mention a graph/tree, let me know basically how to use it. E.g. Node means ability, level corresponds to damage, then search for the deepest node.

    Read the article

  • Eloqua Sales Awareness Training for Partners - London, November 28-29

    - by Richard Lefebvre
    We are pleased to invite you to the free of charge Oracle Eloqua Sales Awareness Training for Partners - London, November 28&29 - COME LEARN WHAT ALL THE BUZZ IS ABOUT! WHEN SALES & MARKETING BOND, REVENUE GROWS It’s not one thing that makes a company successful with marketing automation – it’s the combination of the best implementation, flexible long-term support and access to a community of marketing innovation that ensures you have the assistance you need every step of the way. Our customers choose Oracle|Eloqua because they know when sales and marketing work together, leads are called upon, quotas are crushed and revenues climb. Learn how Oracle|Eloqua can help you put marketing to work for you! COVERED IN THIS TRAINING Eloqua and the Customer Experience Strategy How Modern Marketing Works Introduction to Eloqua – Whiteboard POV Go To Market Playbook Competitive Landscape Integration Options Service Offerings With case studies, workshops and product demos to help you on your way to a new world of marketing expertise LOGISTICS If you are ready to join us on this journey, now’s the time to let us know! Tell us a little about your experience – complete this form to help us know you better (Please ignore if your firm has already completed) Complete this form to RSVP by Thursday, November 21, 2013. Find out more about the Oracle|Eloqua, join the Oracle Eloqua Marketing Cloud Service Knowledge Zone and keep up on all the news! QUESTIONS? Contact [email protected] Please note that similar events will take place in other cities (Brussels, Istanbul and more come) later in 2014. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman","serif";}

    Read the article

  • How to be successful at BDD Specifications Workshops?

    - by sigo
    Today we tried to introduce BDD in our software development process by having a specification workshop. For this workshop we had 2 developers, 1 tester and 1 business analyst. The workshop lasted 1h30 and by the end of it we managed to figure out some BDD scenarios for our new feature. We tried to focus on finding the scenarios that we could miss, and the difficult ones. At the end of the workshop some people were actually unhappy with the workshop. One developer felt he wasted his time as he was used to be given out the scenarios directly by the business analyst and review them with her. The business analyst didn't feel confident with our scenario coverage (Had a feeling that we could have missed out other important stuff) but more importantly felt that this workshop was also a waste of time as she could have figured out all these scenarios by herself and in a shorter period of time. So my question is how that kind of workshop can actually work. In the theory, given you have a new feature to develop, you put the tree 'amigos' (dev/tester/ba) in the same room so that they can collaborate together on writing the differents requirements for the new feature using examples. I can see all the benefits from that. Specially in term of knowledge sharing and common product/end goal/done vision. But in practice, we still think it is more cost effective to first have a BA to work on his own on the examples and only then to have the scenarios to be reviewed/reworked by the 3 'amigos'. By having the BA to work on his own, we actually feel more confident that we are less going to miss out stuff + we still get to review the scenarios afterward to double check. We don't think than simple brainstorming/deliberate discovery is actually enought to seriously cover all the requirement for a feature. The business analyst is actually the best person for that kind of stuff. The thing we just do is to review what she wrote and see if then we have a common understanding (which could then lead to rewrite some of her scenarios or add new ones she could have missed). This workshop lasted 1h30, and by the end of it, we didn't feel confident enought about wha we did...sure we could have spent more time on it but honestly most people get exhausted after 1h30 of brainstorming. So how can you get that to work effectively in practice ?

    Read the article

  • Determining cause of random latency/loading issues

    - by Sherwin Flight
    I'm not sure exactly what details to post in regards to my issue, because I'm not sure what is relevant. Prior to the end of September my websites all loaded quickly, in almost all cases. Loading time wasn't usually more than a few seconds. However, since the end of September I noticed a big increase in page loading times. In some cases pages were taking 30 seconds or more to load. I do have a remote monitoring service monitoring some of the sites as well, and the image below shows the response times over the past month. The response times shown at the beginning of this graph were what the usual response times were prior to this issue occurring. You can see that there has been a significant increase in response times from the beginning to the end of this graph. The thing is, the problem is not happening 100% of the time. If I click through the site, or even just keep refreshing the page, about 25% of the time the pages load quickly, the remaining 75% of the time they load slowly. Sometimes the pages take so long to load that they time out, and don't load at all. I have contacted my hosting provider, and they said things at their end was fine. I don't believe the problem is my home internet provider, because all other websites load without a problem. The server is located in Texas, USA. This also raises another interesting point. My remote monitor checks my site from two locations, California, USA, and London, England. As you can see in the chart below the response time is actually shorter when checked from London, which doesn't seem to make sense, since the server is physically closer to the California monitoring location. I would have expected the London monitoring location to have higher response times since they are physically farther away. I should also point out that in some traceroute test I've done it seem like the first connection to the server seems to take the longest, then after that the rest of the page loads quickly. Below is a little chart showing the times for the first connection to the server. So, what could be causing this problem, and what steps can I take to resolve it or at least narrow down the problem? Sending the request to the server was very quick, and receiving the reply back seems pretty quick, but the WAIT time is really long. So it connects, sends the request, but then waits close to 30 seconds before it starts receiving data back. I am also aware that there are things I can do to speed up page loading times, like reducing the number of css/js files used on a page, compressing images, etc. This is not really what the source of the problem is though, because nothing has really changed on the site since before the problem started, and other sites on the same server are loading slowly as well. Any help or advice is much appreciated.

    Read the article

  • SSH from external network refused

    - by wulfsdad
    I've installed open-ssh-server on my home computer(running Lubuntu 12.04.1) in order to connect to it from school. This is how I've set up the sshd_config file: # Package generated configuration file # See the sshd_config(5) manpage for details # What ports, IPs and protocols we listen for #Port 22 Port 2222 # Use these options to restrict which interfaces/protocols sshd will bind to #ListenAddress :: #ListenAddress 0.0.0.0 Protocol 2 # HostKeys for protocol version 2 HostKey /etc/ssh/ssh_host_rsa_key HostKey /etc/ssh/ssh_host_dsa_key HostKey /etc/ssh/ssh_host_ecdsa_key #Privilege Separation is turned on for security UsePrivilegeSeparation yes # Lifetime and size of ephemeral version 1 server key KeyRegenerationInterval 3600 ServerKeyBits 768 # Logging SyslogFacility AUTH #LogLevel INFO LogLevel VERBOSE # Authentication: LoginGraceTime 120 PermitRootLogin no StrictModes yes RSAAuthentication yes PubkeyAuthentication yes #AuthorizedKeysFile %h/.ssh/authorized_keys # Don't read the user's ~/.rhosts and ~/.shosts files IgnoreRhosts yes # For this to work you will also need host keys in /etc/ssh_known_hosts RhostsRSAAuthentication no # similar for protocol version 2 HostbasedAuthentication no # Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication #IgnoreUserKnownHosts yes # To enable empty passwords, change to yes (NOT RECOMMENDED) PermitEmptyPasswords no # Change to yes to enable challenge-response passwords (beware issues with # some PAM modules and threads) ChallengeResponseAuthentication no # Change to no to disable tunnelled clear text passwords #PasswordAuthentication yes # Kerberos options #KerberosAuthentication no #KerberosGetAFSToken no #KerberosOrLocalPasswd yes #KerberosTicketCleanup yes # GSSAPI options #GSSAPIAuthentication no #GSSAPICleanupCredentials yes X11Forwarding no X11DisplayOffset 10 PrintMotd no PrintLastLog yes TCPKeepAlive yes #UseLogin no #MaxStartups 10:30:60 #Banner /etc/issue.net Banner /etc/sshbanner.net # Allow client to pass locale environment variables AcceptEnv LANG LC_* Subsystem sftp /usr/lib/openssh/sftp-server # Set this to 'yes' to enable PAM authentication, account processing, # and session processing. If this is enabled, PAM authentication will # be allowed through the ChallengeResponseAuthentication and # PasswordAuthentication. Depending on your PAM configuration, # PAM authentication via ChallengeResponseAuthentication may bypass # the setting of "PermitRootLogin without-password". # If you just want the PAM account and session checks to run without # PAM authentication, then enable this but set PasswordAuthentication # and ChallengeResponseAuthentication to 'no'. UsePAM yes #specify which accounts can use SSH AllowUsers onlyme I've also configured my router's port forwarding table to include: LAN Ports: 2222-2222 Protocol: TCP LAN IP Address: "IP Address" displayed by viewing "connection information" from right-click menu of system tray Remote Ports[optional]: n/a Remote IP Address[optional]: n/a I've tried various other configurations as well, using primary and secondary dns, and also with specifying remote ports 2222-2222. I've also tried with TCP/UDP (actually two rules because my router requires separate rules for each protocol). With any router port forwarding configuration, I am able to log in with ssh -p 2222 -v localhost But, when I try to log in from school using ssh -p 2222 onlyme@IP_ADDRESS I get a "No route to host" message. Same thing when I use the "Broadcast Address" or "Default Route/Primary DNS". When I use the "subnet mask", ssh just hangs. However, when I use the "secondary DNS" I recieve a "Connection refused" message. :^( Someone please help me figure out how to make this work.

    Read the article

  • Dual booting windows 8/ubuntu 12.04.2, Grub doesn't appear and machine never boot in ubuntu

    - by black sensei
    i got a new ACER predator AG3620-UR308 which came with windows 8, so i wanted to run ubuntu 12.04.2 on it as a dual booting. To be honest, i've been doing dual booting for a while now so, i did the right thing. the box came with 2TB HDD. so i made 4 partitions with a raw partition just after the windows installation partition I always do manual installation so even if ubuntu didn't detect windows 8, it was ok for me. So i created swap area and finished the installation etc....Grub was install on the only drive there which is sda. After reboot, grub doesn't even come up.So it always boot in windows 8. I did repeat the installation process twice and yield same result. which is weird because this method always works for me so far.Even the laptop am using to write this post is a dual booting windows 7/ mint nadia installed the same way. Is there anything new in windows 8 that i didn't make provision for? Before starting the installation, all i read about was that , windows 8 should be installed first and ubuntu after. I went ahead and disable secure boot from the BIOS and enabled CSM (don't even know what it means) according to Acer custhelp site . I boot from USB and did fdisk -l bellow is the result: ubuntu@ubuntu:~$ sudo fdisk -l WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted. Disk /dev/sda: 2000.4 GB, 2000398934016 bytes 255 heads, 63 sectors/track, 243201 cylinders, total 3907029168 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 4096 bytes I/O size (minimum/optimal): 4096 bytes / 4096 bytes Disk identifier: 0x8c361cb5 Device Boot Start End Blocks Id System /dev/sda1 1 3907029167 1953514583+ ee GPT Partition 1 does not start on physical sector boundary. Disk /dev/sdb: 8178 MB, 8178892800 bytes 255 heads, 63 sectors/track, 994 cylinders, total 15974400 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk identifier: 0x0006a87e Device Boot Start End Blocks Id System /dev/sdb1 * 2048 15972351 7985152 b W95 FAT32 ubuntu@ubuntu:~$ Can anybody shed some light? thank you in advance EDIT Hey, i just did another trial with 13.04 this time and still no luck. bios: secure-boot: disabled enable CSM : always 1-delete previous ubuntu partition and swap area partition.now having free space 2- used usb installer to prepare usb with ubuntu-13.04-desktop-amd64.iso 3- rebooted : liveusb didnt detect windows 8, used something else 4-created partition ext4 for / 5-created partition for swap-area 6- default grub path is /dev/sda and clicked install Acer always boots into windows.

    Read the article

  • How to deal with malicious domain redirections?

    - by user359650
    It is possible for anybody to buy a domain name containing negative terms and point it to someone's website in order to damage their reputation. For instance someone could buy the domain child-pornography.com and point it to the address 64.34.119.12 which is the address behind stackoverflow.com and people navigating to the domain in question would end up visualizing content from StackExchange which would be detrimental to StackExchange's image. To illustrate this, I added the entry 64.34.119.12 child-pornography.com to my /etc/hosts file and tested. Here is what I obtained: I personally found this user experience terrible as someone could think that Stack Exchange are in favor of child pornography and awaiting support from the community to create a Q&A site about it. I tested with other websites and experienced other behaviors that I would categorize as follows: 1 - Useful 404 page (happens with stackoverflow.com): For me the worst way of handling this as the image of the targeted website is directly associated with the offending domain. The more useful the 404 page, the bigger the impression that the targeted website would be willing to help with child pornography. 2 - Redirection (happens with microsoft.com): For instance when accessing child-pornography.com you get redirected to www.microsoft.com. It isn't as bad as above as the offending domain name never appears alongside the targeted website's content, but still bad in my opinion as it gives the impression the targeted website bought the offending domain and redirected it to their website to get more traffic. 3 - Server error (happens with lemonde.fr): You get an error from the webserver which page doesn't contain any content that can be associated with the targeted website (e.g. default Apache 404 page, completely blank page). I believe that is good as the identify of the targeted website isn't revealed. Above are the various behaviors I experienced, but I also thought about a fourth way of dealing with this which is described below. 4 - Disclaimer page (haven't found any website implementing that technique): Display a message such as : "You ended here because someone bought and linked the child-pornography.com domain to our website. We do not own this domain and do not associate ourselves with it. This request has been logged by our servers and we will raise this issue with the competent authorities to have this domain taken down. If you want to access our website, please click here." The good thing about this method is that it can be implemented at application layer (good if you don't have control over web server which happens with some hosting solutions), allows you to protect yourself from any liability, and offer the visitor to be redirected to your own website. Which of the above options would you implement to deal with malicious domain linking (IMO only options 3 and 4 are worth considering) ?

    Read the article

  • What to answer to a customer who asks which one of two equivalent technologies must be used?

    - by MainMa
    As a freelancer, I am often asked by my customers what they must choose between similar elements, neither of which being better than another. Examples: “Do I need my e-commerce website be in PHP or ASP.NET?” “Do I need to host this ordinary web service in Cloud or use an ordinary hosting service?” “Which one is better for my new website: MySQL or Oracle?” etc. There is maybe at most 1% of cases where the choice is relevant, and there is a real, objective reason to use one over another, based on the precise metrics and studies. In all other cases, it doesn't matter at all. It is totally, completely irrelevant, either because there are no implications¹, or because those implications are too small to be taken in account², or, finally, because it's impossible to predict those implications³. If you know one thing and not another one, the answer to those questions is easy: “You can either write the application in C# or Java, both being probably equivalent in your case. Note that I'm a C# developer, so if you choose Java, I would not be able to work on your project and you would need to find another freelancer.” When you know both technologies, you can't answer that. In this case, how to explain to the customer that the question he asks is subject to flamewar and has no real consequences on his project? In other words, how to explain that you've chosen to use one technology rather than an equivalent one for the reasons related to human resources, without giving the impression to be unprofessional or to not care about the project? ¹ Example: Is MySQL better (worse?), performance-wise, compared to Oracle, for a personal website which will be accessed by, oh, let's be optimistic, two people per day? ² Example: for a given project, I was asked to asset if Windows Azure hosting would be cheaper than the hosting of the same application on a well-known ASP.NET hosting provider. The cost revealed to be exactly the same. ³ Example: your customer have an idea of a future application (the idea itself being extremely vague). There is no business plan, no requirements, nothing at all. Just an idea. You are asked if Java is better than C# for this app. What do you answer?

    Read the article

< Previous Page | 511 512 513 514 515 516 517 518 519 520 521 522  | Next Page >