+ Post New Thread
Page 2 of 3 FirstFirst 123 LastLast
Results 16 to 30 of 41
Windows Server 2008 R2 Thread, Network issues with network over last week. in Technical; Great idea but you might want to fix the problems first....
  1. #16


    Join Date
    Jan 2006
    Posts
    8,202
    Thank Post
    442
    Thanked 1,032 Times in 812 Posts
    Rep Power
    339
    Great idea but you might want to fix the problems first.

  2. #17


    Join Date
    Sep 2007
    Location
    UK
    Posts
    5,373
    Thank Post
    1,417
    Thanked 865 Times in 556 Posts
    Rep Power
    642
    We have similar symptoms but more intermittent. There are currently two nics that are teamed. Tomorrow, as part of the elimination process, we will try just one nic and see what happens.

  3. #18

    Join Date
    Jul 2007
    Location
    West Sussex
    Posts
    264
    Thank Post
    35
    Thanked 11 Times in 11 Posts
    Rep Power
    16
    I just wanted to update this thread with the current situation.

    I haven't resolved the issue but I have got a lot less srv errors on the server. From looking at the logs the srv errors only occur during the day when the network is in use suggesting it's switch/bandwidth issues or a certain piece of hardware. The last srv error we had was at 12:53 yesterday afternoon and we appear to be getting less and less *touch wood*. Unfortunately I'm still experiencing users loosing their redirected desktops, start menus, or temporary access to mapped drives and it's driving me crazy. All these are redirected from the main server which was having the srv errors and dropping remote sessions intermittently.

    What did seem to slightly relieve the issue was to plug the server into a different port on our 4108gl switch which is our main switch in our server room, since then the srv errors have decreased but the icons still go missing etc. I suspect that it might be this switch causing the issues. One thing I forgot to mention is that we had a long power cut Wednesday night and all our servers, etc shut down.
    I haven't as yet upgraded the firmware on the switch as I'm very nervous about doing so as it is our main switch and I don't currently have a spare. Another thing I'm considering doing is teaming the broadcom NIC's in the server to spread the bandwidth (now that I'm getting less srv errors).

    Could it be bandwidth related that users intermittently loose their icons, etc? It does suggest so as the busier the network gets the more the problem shows itself, all was fine until last week though?!?

    Another thing I've done is upgraded Sophos on all of our clients to 10.2 from 10.0 yesterday morning (not that I think this will effect anything but thought I should let you know).

    Further feedback and advice is much appreciated.

    Thanks

  4. #19
    chazzy2501's Avatar
    Join Date
    Jan 2008
    Location
    South West
    Posts
    1,781
    Thank Post
    213
    Thanked 263 Times in 213 Posts
    Rep Power
    67
    Have you tried disabling some of the hardware accelerations on the NIC? (flow control, arp offloads, tcp offloads) I find this helps if the driver is funny. (some of those options mess up tcpip)

  5. #20
    cpjitservices's Avatar
    Join Date
    Jul 2010
    Location
    Hessle
    Posts
    2,421
    Thank Post
    508
    Thanked 282 Times in 258 Posts
    Rep Power
    81
    Are you using VLANS ?

    You could separate all of your servers, pc's, phones into VLANs and see if that improves, segregate your broadcast domains because if your not using VLANs your entire switch is a broadcast domain and it could be slowing your network. Especially if you have a broadcast storm. Sounds to me actually like you *might* have a switch loop somewhere, watch out for the port LED's on your switch flashing really fast or more than usual, especially if they all do it at the same time.

    A bit like this:
    http://www.youtube.com/watch?v=LvOkGLEG1Nw
    Last edited by cpjitservices; 1st May 2013 at 10:10 AM.

  6. #21

    seawolf's Avatar
    Join Date
    Jan 2010
    Posts
    969
    Thank Post
    12
    Thanked 283 Times in 217 Posts
    Blog Entries
    1
    Rep Power
    175
    Quote Originally Posted by IT_Man_Dan View Post
    I just wanted to update this thread with the current situation.

    Further feedback and advice is much appreciated.

    Thanks
    Have you used Wireshark to see what is going on at the time of the SRV errors and other issues? You might also want to look at using MRTG or PRTG to check the bandwidth on all of the ports (or download and install OpManager, you get full features for the trial period).

    Also, is this server a VM or a physical server? I have seen similar issues occurring when a server was being pushed beyond its capacity, particularly in regards to disk I/O. If you are seeing high read or write latencies, then you will want to look into that further. This will cause some big problems with VM servers in particular.

  7. #22

    Join Date
    Jul 2007
    Location
    West Sussex
    Posts
    264
    Thank Post
    35
    Thanked 11 Times in 11 Posts
    Rep Power
    16
    The server is a physical one.

    My NIC advanced settings are listed below, please can you advise any changes to them that I should make?

    Broadcom BCM5716C NetXtreme 2 GigE (NDIS VBD Client)

    Ethernet@wirespeed = Enabled
    Flow Control = Disable
    Interrupt moderation = Enable
    IPV4 Checksum Offload = TX/RX Enable
    IPV4 Large send offload = Enable
    IpV6 Checksum = TX/RX Enable
    IPV6 Large Send Offload = Enable
    Jumbo MTU = 1500
    Locally Administered Address = Not Present
    Number of RSS queues = 8
    Priority and VLAN = Priority and VLAN Enabled
    Receive Buffers = 750
    Receive Side Scaling = Enable
    Speed & Duplex = Auto
    Transmit Buffers = 1500
    VLAN ID = 0

    Thanks for your help.

  8. #23

    seawolf's Avatar
    Join Date
    Jan 2010
    Posts
    969
    Thank Post
    12
    Thanked 283 Times in 217 Posts
    Blog Entries
    1
    Rep Power
    175
    Quote Originally Posted by IT_Man_Dan View Post
    The server is a physical one.

    My NIC advanced settings are listed below, please can you advise any changes to them that I should make?

    Broadcom BCM5716C NetXtreme 2 GigE (NDIS VBD Client)

    Ethernet@wirespeed = Enabled
    Flow Control = Disable
    Interrupt moderation = Enable
    IPV4 Checksum Offload = TX/RX Enable
    IPV4 Large send offload = Enable
    IpV6 Checksum = TX/RX Enable
    IPV6 Large Send Offload = Enable
    Jumbo MTU = 1500
    Locally Administered Address = Not Present
    Number of RSS queues = 8
    Priority and VLAN = Priority and VLAN Enabled
    Receive Buffers = 750
    Receive Side Scaling = Enable
    Speed & Duplex = Auto
    Transmit Buffers = 1500
    VLAN ID = 0

    Thanks for your help.
    What's the MTU seton the switch port the server is connected to? If it doesn't match the server, then that spells trouble. Also, I would be more inclined to leave flow control turned on at the NIC and disable it on the switch ports (all of them). However, if its off both on ALL of your NICs OR off on ALL switch ports then that won't be the cause of any problems. The sudden occurrence of your problem would seem to rule out flow control being an issue unless you have recently added any new devices (NICs) to the network that would correlate to the timing of your problems.

  9. #24

    Join Date
    Jul 2007
    Location
    West Sussex
    Posts
    264
    Thank Post
    35
    Thanked 11 Times in 11 Posts
    Rep Power
    16
    Argghhh 10 srv errors within the last hour and all icons etc keep disappearing intermittently..

  10. #25
    chazzy2501's Avatar
    Join Date
    Jan 2008
    Location
    South West
    Posts
    1,781
    Thank Post
    213
    Thanked 263 Times in 213 Posts
    Rep Power
    67
    well as flow control is off turn it on. This should stop packet loss due to high traffic. (This is believe is already built into the tcp stack so you shouldn't need it)

  11. #26


    Join Date
    Jan 2006
    Posts
    8,202
    Thank Post
    442
    Thanked 1,032 Times in 812 Posts
    Rep Power
    339
    Quote Originally Posted by IT_Man_Dan View Post
    Argghhh 10 srv errors within the last hour and all icons etc keep disappearing intermittently..
    and the ARP table on the switch says?

  12. #27
    cpjitservices's Avatar
    Join Date
    Jul 2010
    Location
    Hessle
    Posts
    2,421
    Thank Post
    508
    Thanked 282 Times in 258 Posts
    Rep Power
    81
    Unplug everything.... And I mean everything, plug in each device one by one, and test connections so plug in your server and plug in say 10 machines and see if you get any drop outs, if you do unplug everything until you can nail it down to a device, one device on a flat network can break everything.

    Reboot your switch also before you plug anything back in. If you do get drops it may indicate a certain device or cable. If you still get drop outs and you've done this with every device they I would say it's your infrastructure cabling rather than a config problem. Also is spanning-tree enabled on your switch ? and are you using VLANs ?

  13. #28
    DMcCoy's Avatar
    Join Date
    Oct 2005
    Location
    Isle of Wight
    Posts
    3,424
    Thank Post
    10
    Thanked 488 Times in 428 Posts
    Rep Power
    111
    Of course it could be something like the AntiVirus network filter, I've seen something similar with avg business edition at a site.

  14. #29
    cpjitservices's Avatar
    Join Date
    Jul 2010
    Location
    Hessle
    Posts
    2,421
    Thank Post
    508
    Thanked 282 Times in 258 Posts
    Rep Power
    81
    Yeah I've had issues with Sophos, It was eating resources to the point where if you did a speedtest on a machine that was on a gig connection you'd get 6 meg. That was with the Internet Security running.

  15. #30
    zag
    zag is offline
    zag's Avatar
    Join Date
    Mar 2007
    Posts
    3,762
    Thank Post
    897
    Thanked 416 Times in 350 Posts
    Blog Entries
    12
    Rep Power
    86
    Just buy a cheap gigabit switch for the server room and plug it in. Should be able to test it in minutes.

SHARE:
+ Post New Thread
Page 2 of 3 FirstFirst 123 LastLast

Similar Threads

  1. Replies: 6
    Last Post: 27th February 2013, 09:35 PM
  2. Issues with network ??
    By detjo in forum Windows
    Replies: 3
    Last Post: 3rd October 2011, 04:47 PM
  3. Replies: 17
    Last Post: 21st August 2008, 11:28 AM
  4. Replies: 0
    Last Post: 5th April 2008, 10:46 AM

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •