Search Results

Search found 11313 results on 453 pages for 'ip aliasing'.

Page 407/453 | < Previous Page | 403 404 405 406 407 408 409 410 411 412 413 414  | Next Page >

• Have servers behind OpenVPN subnet reach connecting clients

  - by imaginative

  I am trying to find some relevant documentation or what directives I need in either the OpenVPN server configuration or client configuration to accommodate for this use case. I have an OpenVPN server that clients connect to. The OpenVPN server can communicate directly with any of the clients already, this is not an issue. The client is able to reach any machine on the private subnet where OpenVPN resides, this is also not an issue. My issue is that the reverse is currently not possible - I have servers on the same subnet as the OpenVPN box that cannot reach any of the connecting clients. I'd like to be able to SSH to them and more, the same way the client can reach the servers behind the OpenVPN subnet. What do I need to do to make this possible? I already have masquerading rules set on the OpenVPN box: iptables -t nat -A POSTROUTING -s 192.168.50.0/24 -o eth0 -j MASQUERADE IP Forwarding is enabled: echo 1 >/proc/sys/net/ipv4/ip_forward I added a route on the server behind the private subnet to be aware of the route: 192.168.50.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 What am I missing?

  Read the article

• Good HTTP Monitoring tools

  - by ffffff

  I look for HTTP to work with a Linux system server monitor tool every protocol. I know, and will not there be it in whom or a freeware? When, for example, I dump 80/tcp with a packet monitor to be concrete # tethereal -i ppp0 port 80 -x Capturing on ppp0 1244206390.030474 219.111.xx.xx -> 74.125.xx.xx HTTP GET /search?output=js&num=0&dt=1244206414703&client=pub-3031568651010206&q=Cagliari%20Flight&ad=n3&ie=utf8&oe=utf8&channel=0091594208&adtest=off HTTP/1.1 0000 00 04 02 00 00 00 00 00 00 00 00 00 00 00 08 00 ................ 0010 45 00 01 e5 ee 82 40 00 40 06 d2 b5 db 6f 02 5b E.....@[email protected].[ 0020 4a 7d 4f 93 d4 29 00 50 3e df 4c 63 4b 6b 42 e0 J}O..).P>.LcKkB Such output is provided, but there is too much unnecessary information such as an SYN packet or a header. What I want The IP address of the client and sending out character string(Get; the contents of the POST) Among the output character string of the server only as for the HTML (Content-Type:) I am what is chisel) of a thing of text/html. I can set a filter and am the best if only information wanting can accumulate in the log.

  Read the article

• STOP 0x7b booting from iSCSI

  - by Michael

  Hi, I've a Windows 2008 SBS running. It boots of iSCSI. That setup worked for months until yesterday. I intended to reboot and gained a: STOP 0x0000007b INACCESSIBLE_BOOT_DEVICE and no idea why. My setup hasn't changed. No new controller, no new or changed iSCSI targets, no new Network Card or IP address changes. I had all Windows Updates on it. Last known good: same STOP. Allow unsigned drivers: same STOP. Safe mode (all variants): same STOP. Mount target from a client: works. Filesystem check fine. I booted of the SBS DVD but in computer repair options my target doesn't appear. When i choose setup the target appears. So, how can i diagnose what's going wrong? Any helpful tools? Any hints? Thanks in advance Michael

  Read the article

• Why am I experiencing random connection timeouts? (CentOS)

  - by Ryan

  I have a CentOS server setup that currently hosts several websites (all relative of each other in some form or another). As of recently throughout the day at the most random times the website speed will lag to a crawl and eventually hit a connection timeout. When I say random times this typically happens anywhere between 10am and 1pm usually, however, this morning this happened to me at 8am. I do not have a lot of familiarity with server knowledge as far as what I am looking for in this situation. What are some possible causes of why my server is slowing the websites down to a complete crawl or timing out? Are there specific things I should be checking for when this happens? I have noticed using: tail /var/log/httpd/access_log That usually when this down time occurs there are lot of IP addresses related to BingBot, Googlebot, and sometimes various bots or spiders that I am unfamiliar with. Could this be related and if so how can I avoid this from causing my websites to lag out? Thanks in advance for any help or advice. The websites that are timing out are built with PHP and use a MySQL database to display information.

  Read the article

• Consulting: Organizing site/environment documentation for customers?

  - by ewwhite

  Over time, I've taken on consulting and contract engineering work for various clients. More recently, customers are asking for certain types of documentation. These are small businesses and typically do not have dedicated technical staff. Within a single company, Wiki/Confluence/Sharepoint, etc. all make sense as a central repository for documentation and environment information. I struggle with finding a consistent method to deliver the following information to discrete customers. I'm shooting for a process that's more portable, secure and elegant than a simple spreadsheet or the dreaded binder full of outdated information. Important IP addresses, DHCP scope, etc. Network diagram (if needed). Administrative usernames and passwords and management URLs. Software license keys. Support contracts and warranty information. Vendor support contacts and instructions. I know there are other consultants here. Any suggestions or tips on maintaining documentation across multiple environments in a customer-friendly format? How do you do it?

  Read the article

• Configuring nginx to check for hard files in only a few directories,

  - by Evan Carroll

  For a node.js project I'm doing, I have a tree like this. +-- public ¦   +-- components ¦   +-- css ¦   +-- img +-- routes +-- views Essentially, I have the root to be set to public. I want all requests destined to /components/ /css/ /img/ To check to see if their appropriate destinations exist on disk. However, I don't want requests to other directories to even run an IO operation, /foo/asdf /bar /baz/index.html None of those should result in the disk being touched. I have a stansa that does the proxy to node.js, location @proxy { internal; proxy_set_header Host $http_host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_set_header X-NginX-Proxy true; proxy_pass http://localhost:3030; proxy_redirect off; } I just would like to know how to arrange this. My problem would be easily solved if try_files took a single argument, but it always wants a file first. location /components/ { try_files $uri, @proxy } location /css/ { try_files $uri, @proxy } location /img/ { try_files $uri, @proxy } However, there is nothing that I can find that will give me, location / { try_files @proxy } How do I get the effect I want?

  Read the article

• Dual DC Time Service

  - by poconnor

  I believe I'm having an issue with my Domain Controllers and Time Server. On my back up DC, I keep seeing a warning stating "The time service has stopped advertising as a time source because the local clock is not synchronized." Does this mean that my backup DC believes it's a Time Server? My PDC should be the time server and I have gone through setting up the PDC as the time server. I was not around for the original setup of the time server with the old PDC and Backup DC. But I believe the old PDC was the time server so I setup the new PDC as the new time server, when I decommissioned the old PDC. Is it possible that the Backup DC was setup as the time server and it still thinks it's suppose to be giving out time to everyone? Registry for PDC has NTP Registry for Backup has NT5D5 Results of w32tm /monitor Getting AD DC list for default domain... Analyzing:delayoffset from DC1.local..com Stratum: 4 delayoffset from DC1.local..com Stratum: 3 Warning: Reverse name resolution is best effort. It may not be correct since RefID field in time packets differs across NTP implementations and may not be using IP addresses. DC2.local..com[192.168.1.8:123]: ICMP: 1ms NTP: -0.6349491s RefID: DC1.local..com [192.168.1.9] DC1.local..com *** PDC ***[192.168.1.9:123]: ICMP: 0ms NTP: +0.0000000s RefID: wwwco1test12.microsoft.com [65.55.21.20]

  Read the article

• SBS2011 Standard DNS suddenly not resolving some domains

  - by Matt

  Suddenly today I am unable to resolve common domains like serverfault.com, facebook.com; but other domains like google.com, cnn.com work fine. This is on a client machine (Win7 Pro) connected to an SBS2011 Standard domain. The only DNS server is the SBS2011 server. The same domains work fine on all client PCs I have tried, and the same ones do not work. Using nslookup, I get 'no such domain' errors for facebook.com, and the correct DNS entries for the ones that do work. When I add Google's Public DNS to my client PC as a backup (primary = local SBS server, secondary = 8.8.8.8), everything works fine for my client PC, but querying from the SBS server directly or from other client PCs are broken (so I don't believe it's a firewall issue). My main question is how can I see what servers the SBS2011 server queries if it doesn't know about a domain? There is nothing in our firewall logs that say it blocked any DNS-based packets, but I also wanted to query based on the IP/FQDN on the servers that the SBS server was likely to contact to find out about facebook.com for example. Update 23/05/2012: It appears DNS is working again this morning for the affected websites. Both the DC on its own and all client PCs can once again access the websites that were not loading last night, as well as the websites that were working. I haven't changed anything overnight, so it appears that there was some kind of temporary glitch, but I can't understand what would have caused it on the network.

  Read the article

• Vmware Workstation, Win7 host, Ubuntu guests with Nat + Host-only networks but they cannot connect to the Internet

  - by Ikon

  I have a Win7 host machine with Vmware Workstation. In the workstation I have 3 Ubuntu installed. All 3 Ubuntu guests have a Nat network - to access the internet without asking the router for a local address - and a Host-only network - to connect all Ubuntu quests and the host in a private network for internal communication, without touching the router. When I try to make any of the Ubuntu quests to get data from the internet - assuming that they would figure out that the Nat-ed interface can access the requested data - they fail and report that there is no route to my query. If I disconnect the 2nd interface on the Ubuntu guests with the Host-only network and restart networking, they start to know the route to the internet. Odd, during the installation of the guests they asked which of the 2 given interfaces - with Nat and Host-only config - should be used to get updates during installation and they oddly managed to get the updates. Not so after the installation has finished and rebooted. I have checked the Virtual Network Editor that the Nat interface should use my real network card to access the net, so there should be no problem. I wish not to use the router's dhcp service to give the Ubuntu quests an address, and also I don't want the guests to be accessable from the local network directly, but only by the host - that's the Host-only network is for. Any suggestions? Edit: 192.168.189.0 is the Nat interface and 192.168.7.0 is the Host-only. $ route -n Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.7.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1 192.168.189.0 0.0.0.0 255.255.255.0 U 0 0 0 eth0 0.0.0.0 192.168.189.2 0.0.0.0 UG 100 0 0 eth0

  Read the article

• How do I access my webserver on my stationary from my laptop?

  - by Steven

  I'm running Apache on my stationary and I would like to access a website through my laptop. This is some of the Apache config: NameVirtualHost 127.0.0.1:80 <VirtualHost 127.0.0.1:80> ServerName mysite.com DocumentRoot I:/wamp/www/mysite/ </VirtualHost> ServerName localhost:80 <Directory /> Options FollowSymLinks AllowOverride all Order deny,allow Deny from all </Directory> On my laptop I've added the following to the HOSTS file: 10.0.0.3 mysite.com But accessing the page through mysite.com is not very successfull. If I enter the IP address directly, I only get a Forbidden message. What do I need to do in order to get this to work? Update I'm runing WAMPSERVER 2.1 (Apache 2.2.17) Apache is up and running I can ping 10.0.0.3 from laptop I'm not able to ping http://mysite.com from laptop IE gives me a 403 Forbidden - The website declined to show this webpage The only log that get's entries when trying to access the website from my laptop, is access.log. access.log 10.0.0.4 - - [13/Jun/2011:10:14:04 +0200] "GET / HTTP/1.1" 403 202 apache_error.log [Mon Jun 13 10:08:16 2011] [error] VirtualHost localhost:0 -- mixing * ports and non-* ports with a NameVirtualHost address is not supported, proceeding with undefined results UPDATE 2 My apache config has the following entry: AllowOverride all Order Deny,Allow Deny from all Allow from 127.0.0.1 Could it be that this Allow from is stopping other computers accessing the page?

  Read the article

• Routing and authenticating all access through squid

  - by Knight Samar

  Hi, I want to route all Internet access in my network through a Squid proxy server and authenticate and log all users. I want this to be a client-independent setting so that no one needs to do anything on their browsers or machines. I have set my network gateway as the proxy server so that all traffic will be sent to it. I have done this using options in DHCP server. Now I tried using squid as a transparent proxy, but then it won't authenticate in that mode. I tried using iptables to route all traffic to port 3128 but it won't popup the authentication dialog box from SQUID. I tried telling DHCP to give WPAD to all clients by placing a WPAD file on a webserver containing the following for automatic proxy configuration on clients: Changes in dhcpd.conf option wpad code 252 =test; option wpad "\n\000"; option wpad "http://192.168.1.5/wpad.dat\n"; The WPAD file: function FindProxyForURL(url,host) { return "PROXY squid-server-ip-address:3128 ; DIRECT "; } But the browsers (different versions of Firefox and IE) seem to ignore it. :( What should I do ?

  Read the article

• Ubuntu: Network connection seems to fail after some time

  - by chrischu

  I just bought a Shuttle XS-35 barebone mini-PC and put a 1 TB WD hard drive and 2 Gigs of RAM into it and installed Ubuntu onto it. The machine will post as a media server (streaming videos to my PS3) and as a webserver for some small private projects. Now I wanted to copy my videos from my Windows 7 machine to the Ubuntu machine and therefore created a Samba share on the Ubuntu machine. I tried copying the files with the standard Windows copy function and with SyncToy but after some time (sometimes 5 copied files, sometimes 120 copied files) the Samba share just disappears. When that happens I can't reach the internet from the Ubuntu machine although the network connection still seems to be fine (IP still there etc.). Between the machines lies a LinkSys router. When I try to ping my router (after the connection doesn't work anymore) from the Ubuntu machine only a very small subset of the packages actually get there (something around 20%). When I restart the Ubuntu machine everything seems to work normal again. I have no idea where the problem lies here. Does anybody have a clue? Thanks in advance!

  Read the article

• Correct use of SMTP "Sender" header?

  - by Eric Rath

  Our web application sends email messages to people when someone posts new content. Both sender and recipient have opted into receiving email messages from our application. When preparing such a message, we set the following SMTP headers: FROM: [email protected] TO: [email protected] SENDER: [email protected] We chose to use the author's email address in the FROM header in an attempt to provide the best experience for the recipient; when they see the message in their mail client, the author is clear. To avoid the appearance of spoofing, we added the SENDER header (with our own company email address) to make it clear that we sent the message on the author's behalf. After reading RFCs 822 and 2822, this seems to be an intended use of the sender header. Most receiving mail servers seem to handle this well; the email message is delivered normally (assuming the recipient mailbox exists, is not over quota, etc). However, when sending a message FROM an address in a domain TO an address in the same domain, some receiving domains reject the messages with a response like: 571 incorrect IP - psmtp (in reply to RCPT TO command) I think this means the receiving server only saw that the FROM header address was in its own domain, and that the message originated from a server it didn't consider authorized to send messages for that domain. In other words, the receiving server ignored the SENDER header. We have a workaround in place: the webapp keeps a list of such domains that seem to ignore the SENDER header, and when the FROM and TO headers are both in such a domain, it sets the FROM header to our own email address instead. But this list requires maintenance. Is there a better way to achieve the desired experience? We'd like to be a "good citizen" of the net, and all parties involved -- senders and recipients -- want to participate and receive these messages. One alternative is to always use our company email address in the FROM header, and prepend the author's name/address to the subject, but this seems a little clumsy.

  Read the article

• Route web traffic through a separate iterface

  - by tkane

  I'd like to route web traffic through the wlan0 interface and the rest through eth1. Can you please help me with the iptables commands to achieve this. Below is my configuration. Thank you :) Edit: This is about desktop configuration not a web server set up. Basically I want to use one of my connections to browse the web and the other one for everything else. ifconfig: eth1 Link encap:Ethernet HWaddr 00:1d:09:59:80:70 inet addr:192.168.2.164 Bcast:192.168.2.255 Mask:255.255.255.0 inet6 addr: fe80::21d:9ff:fe59:8070/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:33 errors:0 dropped:0 overruns:0 frame:0 TX packets:41 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:4771 (4.7 KB) TX bytes:7081 (7.0 KB) Interrupt:17 wlan0 Link encap:Ethernet HWaddr 00:1c:bf:90:8a:6d inet addr:192.168.1.70 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::21c:bfff:fe90:8a6d/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:77 errors:0 dropped:0 overruns:0 frame:0 TX packets:102 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:14256 (14.2 KB) TX bytes:14764 (14.7 KB) route: Kernel IP routing table Destination Gateway Genmask Flags Metric Ref Use Iface 192.168.2.0 * 255.255.255.0 U 1 0 0 eth1 192.168.1.0 * 255.255.255.0 U 2 0 0 wlan0 link-local * 255.255.0.0 U 1000 0 0 wlan0 default adsl 0.0.0.0 UG 0 0 0 eth1

  Read the article

• Per-mailbox IMAP settings in Exchange 2003 apply successfully but revert to server default

  - by erictheavg

  The title says most of it. I have a Spiceworks mailbox that connects to our Exchange Server 2003 box via IMAP for receiving help desk issues. But for complicated reasons, I want it to receive those emails in text-only format. So, I discovered that you can just go to: Exchange System Manager Administrative Groups First Administrative Group First Storage Group Mailbox Store Mailboxes Right-click the mailbox, Configure Exchange Features Edit the properties for IMAP Set that mailbox to only receive message bodies as plain text. I click OK, then Next, it reports success, and I assume I'm done. But then when I go right back to where I was, I see that "Use protocol defaults" is still checked. Anyone have a clue why this would be? Some other details: I'm logged in as Administrator when I do this. I can't change this setting for the entire IMAP virtual server because some regular users use it. I only have one IP address to play with, which means I can't create another IMAP virtual server. Any suggestions or ideas are greatly appreciated!

  Read the article

• Troubles with apache and virtual hosts

  - by xZero

  I have a BIG problem. I have VPS with Debian OS, and LAMP installed. Fresh install. For control panel i using Webmin. Now i trying to setup multiple sub-domains on my server using webmin for example: downloads.my-domain.com cpanel.my-domains.com forum.my-domains.com But problem what is happening is next, while i using no virtual hosts, everything works perfectly when i accessing it using my-domain.com, but when i add Virtual host, i cann access it but my-domain.com becomes unavilable because it redirects to virtual hosts i added. When i add more than 2 virtual hosts, problem is still here. Also, when i try to access to virtual server for example downloads.my-domain.com, it redirects again to cpanel.my-domains.com When i delete virtual hosts, access to my-domain.com is succesfull... What i known: - That is not problem with my domain provider. I correctly added subdomains and added host record to my VPS IP. - I added unique name to every single virtual host. - There are no two same virtual hosts - Every virtaul hosts have own directory: for example: downloads.my-domain.com have own WWW dir: /var/downloads Can somebody help me? Thanks.

  Read the article

• SSH to remote host (edgemarc 4200 or 4500 series routers) and pull arp data

  - by MaQleod

  I've been trying to think of a method to do this for days, but have not come up with anything yet. Ideally, this is what I'm looking to do: From a windows XP machine, I need to open an SSH connection to a remote host, send the arp command, and pull the text results of the command back for use on the client. I will need to parse this data and preferably produce a 2D array of IPs and MAC addresses. There will be no shared keys, this is all done with a username and password that will always be different, they will need to be fed into the command via variables that will be pulled from a database using an autoit script based on the WAN ip of the remote host. Now the actual parsing of the data and creation of the array will be easy if I can just get the text of the arp table. Is there any way to ssh to a remote host, run a command and return the data from that command to the client in a batch script or perl script (it is ok if it writes the text to a file, I can read it out of the file later, I just need it to get to the client)?

  Read the article

• exim4 seem to stop listening

  - by trakos

  Hey, I have a strange problem with my exim4 configuration. I have a dedicated server running debian for quite a long time now, but I'm not really using it actively recently, so everything just worked due to lack of changes ;) However, recently, my exim4 smtp stopped answering on port 25. It does not respond through localhost, as well - even though it's set to listen on any interface available. Some things I've checked: ks:/home/trakos/Maildir/new# netstat -ap | grep exim tcp 0 0 *:smtp : LISTEN 12521/exim4 ks:/home/trakos/Maildir/new# exiwhat 12521 daemon: -q30s, listening for SMTP on port 25 (IPv4) ks:/home/trakos/Maildir/new# cat /var/log/exim4/rejectlog ks:/home/trakos/Maildir/new# cat /var/log/exim4/paniclog The queue is set for 30s only because I was running it in a non-daemon mode to see any output. Strangely enough, no suspicious output is given, netstat even shows it is listening on port 25, but still trying to telnet to it times out. The only things that may have changed recently are: I've got second IP for my server I remember that few days ago my spamassasin crashed, and I've started it up again So yeah, I'm really clueless about this one now :P I mean, I don't even know what could be failing here. Could someone give me some ideas what should I check next? PS: it has uptime of 442 days, so I haven't really tried rebooting it yet ^^

  Read the article

• nginx giving of 404 when using set in an if-block

  - by ba

  I've just started using nginx and I'm now trying to make it play nice with the Wordpress plugin WP-SuperCache which adds static files of my blog posts. To serve the static file I need to make sure that some cookies aren't set, that it's not a POST-request and making sure the cached/static file exist. I found this guide and it seems like a good fit. But I've noticed that as soon as I try to set something inside an if my site starta giving 404s on an URL that isn't rewritten. The location block of the configuration: location /blog { index index.php; set $supercache_file ''; set $supercache_ok 1; if ($request_method = POST) { set $supercache_ok 0; } if ($http_cookie ~* "(comment_author_|wordpress|wp-postpass_)") { set $supercache_ok '0'; } if ($supercache_ok = '1') { set $supercache_file '$document_root/blog/wp-content/cache/supercache/$http_host/$1/index.html.gz'; } if (-f $supercache_file) { rewrite ^(.*)$ $supercache_file break; } try_files $uri $uri/ @wordpress; } The above doesn't work, and if I remove all the ifs above and add if ($http_host = 'mydomain.tld') { set $supercache_ok = 1; } and then I get the exact same message in the errors.log. Namely: 2010/05/12 19:53:39 [error] 15977#0: *84 "/home/ba/www/domain.tld/blog/2010/05/blogpost/index.php" is not found (2: No such file or directory), client: <ip>, server: domain.tld, request: "GET /blog/2010/05/blogpost/ HTTP/1.1", host: "domain.tld", referrer: "http://domain.tld/blog/" Remove the if and everything works as it should. I'm stymied, no idea at all where I should start searching. =/ ba@cell: ~> nginx -v nginx version: nginx/0.7.65

  Read the article

• Nginx Server Block Not Working? - Already running other vhosts just this one not working

  - by daveaspinall

  Im running a Debian 6 LEMP server with multiple virtual hosts and everything has been fine for 5 or so sites. But I've just tried adding another but for some reason it's just not working. By not working I mean in Chrome I get the "Oops! Google Chrome could not connect to subdomain.domain.net" error. I've changed the domain for security to subdomain.example.com and the IP is masked. Hosts file (I have multiple sub domains): xxx.xxx.xx.xxx *.example.com *.example Server Block: server { listen 80; server_name subdomain.example.com; access_log /srv/www/subdomain.example.com/logs/access.log; error_log /srv/www/subdomain.example.com/logs/error.log; root /srv/www/subdomain.example.com/public_html; location / { index index.html index.htm index.php; } location ~ \.php$ { include fastcgi_params; fastcgi_pass 127.0.0.1:9000; fastcgi_index index.php; fastcgi_param SCRIPT_FILENAME $document_root$fastcgi_script_name; } } I've created the system link to the file in the /etc/nginx/sites-enabled/ directory and restarted/reloaded nginx. DNS seems fine: # ping -c 2 subdomain PING subdomain.example.com (xxx.xxx.xx.xxx) 56(84) bytes of data. 64 bytes from www.example.com (xxx.xxx.xx.xxx): icmp_req=1 ttl=64 time=0.035 ms 64 bytes from www.example.com (xxx.xxx.xx.xxx): icmp_req=2 ttl=64 time=0.048 ms Checking the file with cURL works: # curl http://subdomain.example.com HTML - OK Emptied browser cache but still no dice. Anything I'm missing? Like I mentioned, I have a few sites running fine on the server currently so php-fpm etc etc are working. Any help would be much appreciated! Cheers, Dave

  Read the article

• Diagnosing Random Network Lag

  - by uesp

  I'm having trouble diagnosing some random lag on a 6 server LAMP cluster serving a MediaWiki site. While we're serving some 100 pages/sec the servers themselves are running fine with less than 0.5 load, no locked processes, no paging, no errors being logged, etc.... Lag is present on all servers and is random: one minute its fine the next it's there. DNS lookups on the servers are randomly slow. For example time nslookup google.com varies randomly from a few milliseconds to several seconds and sometimes times out entirely. While we use IP addresses internally on the cluster this may be a symptom of the root issue. We are not running our own DNS server. The Apache server-status pages randomly lag or time out. Benchmarking using ab between servers shows a few loads sometimes take 3000 ms (almost exactly). Benchmarking server-status on the local server itself usually shows no issue (it showed a lag only once among a few hundred tests). The servers are sitting behind a switch and a firewall which I don't have any access to so I don't know their setup or status. While we are under heavier than normal load a 2 Mbps incoming and 20 Mbps outgoing traffic shouldn't be stressing the switch or firewall should it? My feeling is that it is the switch/firewall or something above them in the ISP like their DNS but can't confirm it. I need some other tests or methods of diagnosing this lag to try and narrow down the ultimate cause.

  Read the article

• Hyper-v and sql server connections for web apps

  - by Rick Ratayczak

  I have a physical machine running win8, and two VMs in hyper-v client: 1 web server, 1 sql server. The web server works fantastic. The sql is the one that is giving me the problem. I can connect to it with server explorer in visual studio or management studio just fine, and it's blazing fast. The problem happens when I use the same connection string I am using in visual studio server explorer in the web.config for an app. data source=VMSQL1;initial catalog=OtherShell;persist security info=True;user id=OtherShell;password=****;network library=dbmssocn;MultipleActiveResultSets=True;App=EntityFramework I made sure it was also using tcp-ip, but it doesn't connect with or without the network library part of the connection string. A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: SQL Network Interfaces, error: 26 - Error Locating Server/Instance Specified) This is driving my batty for the last two days, any ideas? It fails from the web vm too, but works in management studio with the same connection string.

  Read the article

• Is it possible to trace someone using Google during an online exam?

  - by George

  I happen to be a professor at a reputed college. I want to design an online exam for over 1000 students via around 50 computers right after the vacation ends. Now the problem is that I have heard that many students use Google on a different tab to find answers when no invigilator is around. I want to know if there is a way to backtrace it after the exams via some kind of history or any other possible way. In our university there is a standard system. I am not good with computers but I will try to explain. Each computer uses mozilla to connect to a server centrally located via an IP. The students open it and enter a unique ID and password to start the exams. Many questions are jumbled and different groups of students give exam in a different time slot. Is there any way to trace it since I want to set an example for students so they won't cheat and give exams in an honest way. Additional details: Since the number of computers are less than the number of students, more than 10 students are going to use a single computer on a single day over a period of 10 hours. After this, if I check the history (and let's say someone even forgot to delete the history and I see it), will I able to figure out who among the 10 has done it? Moreover, is it even practical and feasible?

  Read the article

• Can't reliably ping 6224 router from directly-attached system

  - by David Mackintosh

  OK, here's my situation. This is on the internet. The 6224 is the router in this picture and physically resides in Kanata. Both VLAN 1697 and 3994 are provided by an internet service provider. These VLANs are provided through a single 1Gb ethernet wire. The Kanata hosts are directly attached to the 6224; the other two sites are remote. VLAN 3994 is a single IP address space, so theoretically it shouldn't matter physically where the hosts on that subnet are. Here's the problem. I have a monitoring system which is connected further into the internet, so probes from the monitor would come in to this diagram on the 1697 VLAN. When I ping hosts at Albert or Bells Corners from the internet, there is 0 loss. The connection looks perfect. When I ping hosts at Kanata, I lose anywhere from 10 to 40% of the pings. The loss is not predictable, but: when I do lose them, I always lose at least 3, usually 4, rarely more, pings in a bunch. I have attached a monitor directly to the 6224 in Kanata on 3994.. When the monitor pings the 6224 routing interface, I see exactly the same loss pattern -- but NOT at the same time as the loss from the remote system. Ping time is around 1ms. When the monitor pings another system directly attached to the 6224, there is 0 loss. Ping time is about 0.1ms, one-tenth of the time to ping the router. Anyone know what is going on here?

  Read the article

• Nginx load balancing and maintaining URLs

  - by Steve Klabnik

  I'm trying to use nginx as a load balancer, and it's working great. One problem, though. The load balancing box is at 123.123.123.123, and the backend box is 456.456.456.456. So I have this config: upstream backend { server 456.456.456.456; } server { listen 80; server_name 123.123.123.123; access_log off; error_log off; location / { proxy_set_header Host $host; proxy_set_header X-Real-IP $remote_addr; proxy_set_header X-Forwarded-For $proxy_add_x_forwarded_for; proxy_pass http://backend; } } This works great. I hit 123.123.123.123 in my browser, and the page comes up. But now the URL in the browser says http://456.456.456.456. Do I need to use a rewrite rule or something to keep the url correct? I don't want it to be different when going to different backed servers. None of the tutorials I've read have mentioned anything about this.

  Read the article

< Previous Page | 403 404 405 406 407 408 409 410 411 412 413 414  | Next Page >