Search Results

Search found 26097 results on 1044 pages for 'network share'.

Page 151/1044 | < Previous Page | 147 148 149 150 151 152 153 154 155 156 157 158  | Next Page >

  • Real benefits of tcp TIME-WAIT and implications in production environment

    - by user64204
    SOME THEORY I've been doing some reading on tcp TIME-WAIT (here and there) and what I read is that it's a value set to 2 x MSL (maximum segment life) which keeps a connection in the "connection table" for a while to guarantee that, "before your allowed to create a connection with the same tuple, all the packets belonging to previous incarnations of that tuple will be dead". Since segments received (apart from SYN under specific circumstances) while a connection is either in TIME-WAIT or no longer existing would be discarded, why not close the connection right away? Q1: Is it because there is less processing involved in dealing with segments from old connections and less processing to create a new connection on the same tuple when in TIME-WAIT (i.e. are there performance benefits)? If the above explanation doesn't stand, the only reason I see the TIME-WAIT being useful would be if a client sends a SYN for a connection before it sends remaining segments for an old connection on the same tuple in which case the receiver would re-open the connection but then get bad segments and and would have to terminate it. Q2: Is this analysis correct? Q3: Are there other benefits to using TIME-WAIT? SOME PRACTICE I've been looking at the munin graphs on a production server that I administrate. Here is one: As you can see there are more connections in TIME-WAIT than ESTABLISHED, around twice as many most of the time, on some occasions four times as many. Q4: Does this have an impact on performance? Q5: If so, is it wise/recommended to reduce the TIME-WAIT value (and what to)? Q6: Is this ratio of TIME-WAIT / ESTABLISHED connections normal? Could this be related to malicious connection attempts?

    Read the article

  • Roughly cutting Fibre Cables

    - by Bryan
    I recently asked a question about which type of Fibre optic cable to use for my installation. We have now found a cable type and supplier and I'm about to order the cable (OM3, Tight Buffered, 12 Core), however I have a further question: We are shortly moving in to a new building (still being constructed) and we are about to get a window in which we will be able to run any cabling that we need. How should I roughly cut the fibre? Can I just use some heavy shears to cut through the cable? I'm aware that doing so will damage the ends, but will the damage be limited to the ends, or could the cracks/fractures continue up the length of the cable? p.s. I have already allowed for several metres of extra cable at each end, and I am going to get a specialist in to terminate the fibres.

    Read the article

  • Wireless to Wireless Transfer Slow on a Linksys WRT54GL

    - by Kyle Brandt
    The Situation: When I try to transfer a file from one computer to another that are both connected via wireless on a WRT54GL (in a office) with dd-wrt firmware I often get bad speeds. In generally they average around 100 kilobytes a second. Either computer can download via wireless from the Internet at at about 2 megabytes a second. The speed is slow with the transfer of one large file. There are about 20 other wireless networks that the computers can see, so there is a lot of noise, but I don't have the equipment to really monitor the frequencies well. But that still seems pretty slow. I thought maybe it was the transmit on each card, but even when they are 5 feet away with a line of sight I still get these speeds. According to Linux both cards are operating at 54g. My Questions: Is this normal for this sort of consumer level wireless equipment? Anything I can do to improve it? why is wireless to wireless transfer slow when everything else isn't? Whats steps might I take to figure out what is happening? For example, are lots of packets not making to the access point requiring retransmissions? Above all, I want to find out what the problem actually is. This may seem odd, but at this point I am more interested in understanding what the problem is than fixing it. What I have tried: I have tried messing with lots of settings. Different channels, xmit power, G-Only, none of which has made anything any better. I've also tried upgrading to newer dd-wrt firmware version and doing a reset to wipe out the settings.

    Read the article

  • Which protocol do clients use when communicating with servers in a SAN

    - by Mario De Schaepmeester
    I'm trying to wrap my head around how a SAN works and how it is implemented. If I understand this well, clients wanting to access the storage devices in a SAN need to communicate with the servers via the LAN. When the SAN is implemented with Fibre Channel, these servers are Fibre Channel compliant devices, and internally in the SAN they work with the Fibre Channel Protocol. Both data and communications are supported by Fibre Channel. But which application-layer protocol do the clients use in the LAN to communicate with the servers? Is the data simply transferred via ethernet as well? This is some part I am stuck on. I went trough a lot of sources but most sources don't really mention protocols and if they do, they only mention FCP.

    Read the article

  • ports only available from the outside network

    - by ChrisJ
    This is a counter-intuitive problem for me. I have a new Win 2003 server on a static IP address w.x.y.z. Tomcat 7, PostgreSQL 9.1, and Subversion are installed. All of it appears to be working fine from the server itself. We can also access the Tomcat manager, web applications, and run "svn ls svn://w.x.y.z/" from outside our network. However, when I try from another machine in the office, phpPgAdmin and svn cannot establish connections with the server. http://w.x.y.z:5432/phppgadmin cannot connect. The svn command from above returns: svn: E730061: Unable to connect to a repository at URL 'svn://w.x.y.z/' svn: E730061: Can't connect to host 'w.x.y.z': No connection could be made because the target machine actively refused it. Tomcat manager and the other web apps we have deployed work fine. Netstat -a from the server shows this: Proto Local Address Foreign Address State TCP SERVERNAME:3690 SERVERNAME:0 LISTENING TCP SERVERNAME:5432 SERVERNAME:0 LISTENING Windows Firewall was off, but just in case I also tried to enable it and open ports 3690 (svn) and 5432 (postgres). No change. I don't have access to the router/switch because it just doesn't work that way in Port-au-Prince and our sysadmin is on R&R. Is there anything that might be causing the problem from the server side?

    Read the article

  • How passively monitor for tcp packet loss? (Linux)

    - by nonot1
    How can I passively monitor the packet loss on TCP connections to/from my machine? Basically, I'd like a tool that sits in the background and watches TCP ack/nak/re-transmits to generate a report on which peer IP addresses "seem" to be experiencing heavy loss. Most questions like this that I find of SF suggest using tools like iperf. But, I need to monitor connections to/from a real application on my machine. Is this data just sitting there in the Linux TCP stack?

    Read the article

  • finding the best network latency between two countries

    - by Yoav Aner
    I know there are many tools to test for bandwidth and latency, but they all rely on having at least one host from which you can run those tests. I wonder whether there's an online source or some other way to guestimate the latency or speed between two countries (in general). For example, would a customer in Japan get lower latency if the server is located in Singapore or Australia? Is a user in India likely to get higher download speed from a server in the UK or in the US? Are there any online resources or some clever ways to answer those questions with a reasonable degree of accuracy? [UPDATE]: Thanks for the great suggestions from Raffael Luthiger. I didn't know about those looking glass servers. The submarine cable maps were also really cool to discover (Thanks to Jesper Mortensen). Also seems really wise if I could ask those network professional in the area for their experience, but obviously I don't have access to those. At least some of them are on SF :) However, I'm still a little unsure how to combine those resources to give me some measurements. This is the information I have: Two countries (A,B). I do have IP addresses of customers in country A (I can obtain those from the web server log files for example). Presumably I can find some looking glass servers in country B and run a trace to those IPs. What's the best measurements to use? Are there any scripts that help automate at least some of this process?

    Read the article

  • Ubuntu Laptop as a wireless hotspot on bridge mode

    - by nixnotwin
    I have a wired router to which my ubuntu laptop connects via ethernet. The wierless NIC of the laptop acts as a wireless hotspot on master mode. I use hostapd fo this. I have bridged eth0 and wlan0, so my wireless clients that connect to my laptop over wifi get ip from the wired router via dhcp, so the devices get registered at the wired router ( and the laptop is just an access point). I use the following commands to get my laptop+accesspoint working: sudo brctl addbr br0 sudo brctl addif br0 eth0 sudo hostapd /etc/hostapd/hostapd.conf & sudo dhclient -d br0 & sudo ifconfig wlan0 192.168.1.15 netmask 255.255.255.0 up sudo brctl addif br0 wlan0 These commands enable me to access internet on my wireless clients and also on the laptop which is acting as wireless accesspoint. But if I reboot the wired router (without rebooting the laptop that is acting as accesspoint), Internet access on the laptop+accesspoint gets lost, but on wireless clients it works fine. Even I have not been able to figure out a command which will reset the laptop interfaces to default settings, so everytime the router reboots, I have to reboot the laptop too to get into default settings so that I can re-enter the above mentioned commands. My first question is How can I have my bridge+accesspoint up and running even-though the router reboots? And is there a command to set the interfaces to a default state? (ifdown -a doesn't work, after issuing the command the bridge still remained).

    Read the article

  • Network Load Balancing, intermittent port problem on Windows Server 2008

    - by Jimmy Chandra
    Trying to troubleshoot an intermittent problem on a Windows Server 2008 NLB. I think it might be related to an NLB issue. We are using Windows Network Load Balancing to balance load for our multiserver SharePoint front ends. Say... Web Front End 1 IP is 192.168.1.100 and Web Front End 2 IP is 192.168.1.101, the NLB is setup to load balance both WFE servers on any incoming traffic to the IP 192.168.1.200. Sometimes we got an intermittent issue where when we try to access the SharePoint site using 192.168.1.200:8080 (say the site is set up to run on port 8080) from a remote client, it will display page not found. Pinging the 192.168.1.200 will give responses, but when trying to telnet to 192.168.1.200:8080 it just won't connect. However, browsing the SharePoint site directly on individual WFE (192.168.1.100 and 192.168.1.101) show no problem whatsoever. My guess also (we didn't get a chance to try it yet, but I think it should work), if I try connecting remotely to individual server, it will respond just fine. But any attempt on trying to connect using the virtual IP (192.168.1.200) will fail miserably. Funny thing is, after a while it will return back to normal. Anyone had similar experience with this type of problem while implementing NLB before? We are doing this in a virtual environment.

    Read the article

  • Getting an alert when my oracle database goes up or down

    - by CodeSlave
    How can I get an e-mail alert when my oracle database comes up or down? I have a database that I need to know when it goes down (it would be nice to know if it has come back up), preferably from a remote machine. Conceivably I could hack together something that TNSPings my DB and e-mails me when that changes, but I'm hoping there's a free package out there. Something that would run on windows. Any strong recommendations?

    Read the article

  • Ubuntu Laptop as a wireless hotspot on bridge mode

    - by nixnotwin
    I have a wired router to which my ubuntu laptop connects via ethernet. The wierless NIC of the laptop acts as a wireless hotspot on master mode. I use hostapd fo this. I have bridged eth0 and wlan0, so my wireless clients that connect to my laptop over wifi get ip from the wired router via dhcp, so the devices get registered at the wired router ( and the laptop is just an access point). I use the following commands to get my laptop+accesspoint working: sudo brctl addbr br0 sudo brctl addif br0 eth0 sudo hostapd /etc/hostapd/hostapd.conf & sudo dhclient -d br0 & sudo ifconfig wlan0 192.168.1.15 netmask 255.255.255.0 up sudo brctl addif br0 wlan0 These commands enable me to access internet on my wireless clients and also on the laptop which is acting as wireless accesspoint. But if I reboot the wired router (without rebooting the laptop that is acting as accesspoint), Internet access on the laptop+accesspoint gets lost, but on wireless clients it works fine. Even I have not been able to figure out a command which will reset the laptop interfaces to default settings, so everytime the router reboots, I have to reboot the laptop too to get into default settings so that I can re-enter the above mentioned commands. My first question is How can I have my bridge+accesspoint up and running even-though the router reboots? And is there a command to set the interfaces to a default state? (ifdown -a doesn't work, after issuing the command the bridge still remained).

    Read the article

  • Software Center doesn't open (elementary luna - ubuntu 12.04)

    - by zbiba
    When i try to open software center on elementary luna i get the bellow error.... ERROR:root:DebFileApplication import Traceback (most recent call last): File "/usr/share/software-center/softwarecenter/db/init.py", line 4, in from debfile import DebFileApplication, DebFileOpenError File "/usr/share/software-center/softwarecenter/db/debfile.py", line 25, in from softwarecenter.db.application import Application, AppDetails File "/usr/share/software-center/softwarecenter/db/application.py", line 27, in import softwarecenter.distro File "/usr/share/software-center/softwarecenter/distro/init.py", line 198, in distro_instance = _get_distro() File "/usr/share/software-center/softwarecenter/distro/init.py", line 175, in _get_distro distro_class = getattr(module, distro_id) AttributeError: 'module' object has no attribute 'debian' Traceback (most recent call last): File "/usr/sbin/update-software-center", line 38, in from softwarecenter.db.update import rebuild_database File "/usr/share/software-center/softwarecenter/db/update.py", line 33, in from softwarecenter.distro import get_distro File "/usr/share/software-center/softwarecenter/distro/init.py", line 198, in distro_instance = _get_distro() File "/usr/share/software-center/softwarecenter/distro/init.py", line 175, in _get_distro distro_class = getattr(module, distro_id) AttributeError: 'module' object has no attribute 'debian'

    Read the article

  • I made a game in XNA - how can I share it with my friends?

    - by Raven Dreamer
    I've just finished programming a charming (albeit bare-bones) XNA version of arcade classic Tempest. Hooray! Given that this was a homework assignment, I'd like to be able to share it with my professor and my friends/classmates to solicit feedback. (And let's be honest - if I have a question about how to add in an additional feature, it might be nice to be able to share it with folks on this site as well.) Is there a better way of sharing an XNA game than by shuttling the visual studio - produced executable around? Some way to host it on a website would be ideal.

    Read the article

  • How to use ipw3945 on Ubuntu 9.04

    - by Aaron
    Note: uname -a 2.6.28-16-generic cat /etc/issue Ubuntu 9.04 \n \l I have disabled iwl3945: cat /etc/modprobe.d/blacklist.conf | tail -3 blacklist iwl3945 blacklist mac8021 Question: How can I use iwp3945 instead?

    Read the article

  • Connecting two pcs through cable, at the same time as wireless

    - by Steffen
    I've got 2 pcs setup with WLAN - however when I copy files between the machines it takes forever (obviously, since I run 801.11g). So I thought, why not just connect them directly with a cable (my wireless router is the other end of the house, that's why I don't use cables to that) However how should I configure the LAN connection on each machine, so I can use it for transferring files between them, whilst using my WLAN to access the Internet ? I was thinking about letting one machine be gateway, but then Windows pops up with a lot of warnings (basically it says this won't work when you're using two disjoint networks) And now I'm at a loss as to what to try.

    Read the article

  • Problem with network after malware attack

    - by Cruelio
    Im trying to help some friends with a Win XP machine. I got rid of the malware using Malware Bytes, and HiJackThis. But now they(I) have another problem. When the computer boot into Windows it seems fine. When I start Internet Explorer the browser window opens just fine, but nothing happens for at minute or two. After the two minutes of waiting, the network icon appears in the taskbar next to the clock, and then everything works. The computer is connected to the internet using a Ethernet adapter. I have looked at the Rvent Log and found an error from Perfnet with eventid 2004 <Provider Name="PerfNet" /> <EventID Qualifiers="49152">2004</EventID> <Level>2</Level> <Task>0</Task> <Keywords>0x80000000000000</Keywords> What I have tried so far: In the device manager i have uninstalled the Ethernet adapter and installed it again. I have uninstalled and installed the Windows File and Printer Sharing service. I have verified that both server and workstation services are started. What should I do next?

    Read the article

  • Play system sounds from one computer through another computer's speakers?

    - by kevinconner
    I have a Mac and a Windows PC at work. I use both at the same time with Synergy and SynergyKM, which is a great setup for me. The Mac has built-in speakers and the PC has a sound card, but no speakers. I don't want to get speakers for use at work; instead I'd rather just have all sounds from both computers play through the Mac's speakers. Is there some sort of audio service I can run on each computer to accomplish that? I would want: System alert sounds, like you configure in the Control Panel Sounds from videos in a web browser, including from Flash

    Read the article

  • Service monitoring service, which I can ping instead of getting pinged

    - by Jack Juiceson
    I'm looking for a service, which can send me an alert if my program didn't ping(some http request) in X minutes. Pretty much like any service monitoring, but instead of service pinging my server I want, my program to ping the monitor service. This is because our program, can't get incoming connections, yet we need to monitor it's alive. And easiest for us will be to have a service we can ping. Thank you, - Jack

    Read the article

  • How to access remote network resource from local machine

    - by jerluc
    I just configured VPN access successfully so that I now can connect to my workstation at work from my personal Linux box at home. The problem is that all of my dev files for a server I'm locally running are on my personal box and cannot be transfered to my workstation (at least not in any timely manner over this connection given the amount of data, in addition to the many reconfigurations which would be required for the server to run even if I could somehow get the files across). So essentially, I am able to run my server locally on my personal computer, however, the data-sources required for the back-end are accessible only from within the office's network. But is there some way for me to somehow either access the data-sources directly through a VPN connection or even if I need to be a bit more convoluted by connecting via VPN to my workstation and then somehow connecting to the data-sources through my workstation to my personal computer? And here I could really care less about the speed of the connection from my server to the data-sources since they will probably only be fetched a few times every hour or so. Thanks! Sorry if this a stupid question and/or doesn't make any sense! (And sorry for anyone who read this at stackoverflow, I posted it in the wrong area.)

    Read the article

  • Juniper’s Network Connect ncsvc on Linux: “host checker failed, error 10”

    - by hfs
    I’m trying to log in to a Juniper VPN with Network Connect from a headless Linux client. I followed the instructions and used the script from http://mad-scientist.us/juniper.html. When running the script with --nogui switch the command that gets finally executed is $HOME/.juniper_networks/network_connect/ncsvc -h HOST -u USER -r REALM -f $HOME/.vpn.default.crt. I get asked for the password, a line “Connecting to…” is printed but then the programm silently stops. When adding -L 5 (most verbose logging) to the command line, these are the last messages printed to the log: dsclient.info state: kStateCacheCleaner (dsclient.cpp:280) dsclient.info --> POST /dana-na/cc/ccupdate.cgi (authenticate.cpp:162) http_connection.para Entering state_start_connection (http_connection.cpp:282) http_connection.para Entering state_continue_connection (http_connection.cpp:299) http_connection.para Entering state_ssl_connect (http_connection.cpp:468) dsssl.para SSL connect ssl=0x833e568/sd=4 connection using cipher RC4-MD5 (DSSSLSock.cpp:656) http_connection.para Returning DSHTTP_COMPLETE from state_ssl_connect (http_connection.cpp:476) DSHttp.debug state_reading_response_body - copying 0 buffered bytes (http_requester.cpp:800) DSHttp.debug state_reading_response_body - recv'd 0 bytes data (http_requester.cpp:833) dsclient.info <-- 200 (authenticate.cpp:194) dsclient.error state host checker failed, error 10 (dsclient.cpp:282) ncapp.error Failed to authenticate with IVE. Error 10 (ncsvc.cpp:197) dsncuiapi.para DsNcUiApi::~DsNcUiApi (dsncuiapi.cpp:72) What does host checker failed mean? How can I find out what it tried to check and what failed? The HostChecker Configuration Guide mentions that a $HOME/.juniper_networks/tncc.jar gets installed on Linux, but my installation contains no such file. From that I concluded that HostChecker is disabled for my VPN on Linux? Are the POST to /dana-na/cc/ccupdate.cgi and “host checker failed” connected or independent? By running the connection over a SSL proxy I found out that the POST data is status=NOTOK (Funny side note: the client of the oh-so-secure VPN does not validate the server’s SSL certificate, so is wide open to MITM attacks…). So it seems that it’s the client that closes the connection and not the server.

    Read the article

  • Accessing Windows 7 Printer from Ubuntu Linux via LPR/LPD or Samba

    - by nitbuntu
    Hi, I'm having difficulty printing from my Linux (Ubuntu 10.04) based PC to a printer connected to a Windows 7 machine. I was trying to connect using Samba (version 3.5.6) but this always brings up an authentication screen which never accepts any password I use. So I read somewhere that an alternative is to access the Windows printer via LPR/LPD. I added an LPR/LPD printer in Windows 7, but even within Windows 7, I am not able to print as the print que monitor shows as 'printer busy'. The printer in question is an Epson Stylus DX7400 and works fine when using the standard USB ports....but doesn't when I use with the LPR/LPD ports. I even opened up the TCP/IP port 515 in my McAfee firewall without any success. Any help with this would be highly appreciated. Additionally, does anyone have any idea how I can get Samba working for me?

    Read the article

< Previous Page | 147 148 149 150 151 152 153 154 155 156 157 158  | Next Page >