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Server cannot ping Clients

    Question

  • Hello,

    I have Servers on 10.72.0.0 network and clients are on different network i.e. 10.80.0.0.  Even clients are on different subnets based on their departments and workload. The problematic server is hosted on Hyper-V. But other servers on Hyper-V are not behaving like this.

    One of my server is unable to ping clients. Though clients are able to ping Server. This is happening on one server only, rest of servers are fine and able to ping clients. Even when i am pinging same subnet server i am getting this


    C:\>ping mailstore

    Pinging mailstore.abc.com [10.72.0.91] with 32 bytes of data:

    Reply from 10.72.0.91: bytes=32 time=303632ms TTL=128
    Reply from 10.72.0.91: bytes=32 time=303632ms TTL=128
    Reply from 10.72.0.91: bytes=32 time=303631ms TTL=128
    Reply from 10.72.0.91: bytes=32 time=303631ms TTL=128

    Ping statistics for 10.72.0.91:
        Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
    Approximate round trip times in milli-seconds:
        Minimum = 303631ms, Maximum = 303632ms, Average = 303631ms

    C:\>

    Please help.

     

    Saturday, April 24, 2010 12:37 PM

Answers

  • Hi ,

    sorry for confusion, you can omit the above method.

    I would check few things with respect to hyper-v

    make sure the guest OS has single CPU.

    make use of /usepmtimer switch in boot.ini , you can follow the below link

    http://support.microsoft.com/kb/895980

    • Marked as answer by Tiger Li Thursday, May 06, 2010 1:55 AM
    Tuesday, April 27, 2010 1:06 PM
    Moderator

All replies

  • Hello,

    make sure no firewall is blocking ICMP protocol on the server, which mostly is set by default.


    Best regards Meinolf Weber Disclaimer: This posting is provided "AS IS" with no warranties, and confers no rights.
    Sunday, April 25, 2010 10:45 PM
  • Hello,

    make sure no firewall is blocking ICMP protocol on the server, which mostly is set by default.


    Best regards Meinolf Weber Disclaimer: This posting is provided "AS IS" with no warranties, and confers no rights.

    Meinolf, firewall is off and server is windows 2003.
    Monday, April 26, 2010 2:46 AM
  • Hi Hasan,

    What is the outpu of ping localhost ?

    When did it stopped working ?,

    What happen to file shares , can the client be able to access the file shares and vice versa ?, also try to establish RDP from server to client

    Make sure you reboot the server in safe mode with networking and test the behavior

    Test the behavior by changing the switch port

    Update the NIC drivers to the latest , if you can , try replacing the NIC card

    Finally a Netmon trace / wireshark trace would give you more information , make sure the client is sending packet to DG , if not there is problem related to either switch port or at the OS level.

     

    Tuesday, April 27, 2010 7:43 AM
    Moderator
  • Hi Hasan,

    What is the outpu of ping localhost ?

    When did it stopped working ?,

    What happen to file shares , can the client be able to access the file shares and vice versa ?, also try to establish RDP from server to client

    Make sure you reboot the server in safe mode with networking and test the behavior

    Test the behavior by changing the switch port

    Update the NIC drivers to the latest , if you can , try replacing the NIC card

    Finally a Netmon trace / wireshark trace would give you more information , make sure the client is sending packet to DG , if not there is problem related to either switch port or at the OS level.

     


    The output of localhost as well as other hosts is

    Z:\>ping localhost

    Pinging FF01.abc.com [127.0.0.1] with 32 bytes of data:

    Reply from 127.0.0.1: bytes=32 time=-320722ms TTL=128
    Reply from 127.0.0.1: bytes=32 time=-320722ms TTL=128
    Reply from 127.0.0.1: bytes=32 time=-320722ms TTL=128
    Reply from 127.0.0.1: bytes=32 time=-320722ms TTL=128

    Ping statistics for 127.0.0.1:
        Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),
    Approximate round trip times in milli-seconds:
        Minimum = -320722ms, Maximum = -320722ms, Average = 1073421102ms

    Also i cannot ping clients on other subnet by hostname.

    I dont know since when it is going on, i am just handed over the server to fix it. but its been a long time.

    Yes clients can access file shares and vice versa, RDP is not working from server to client.

    Just to remind you, it is hosted on HYPER-V..........as described above. So it is virtual machine. Services running on it are MOM, ForeFront, SQL.

    Which port i should monitor on WireShark?? DNS related traffic or something else??

    Tuesday, April 27, 2010 9:18 AM
  • Hi ,

    negative values represents errors, and lookat the average its wierd.

    As a first troubleshooting , i would first upgrade the driver or replace it and check.

    Tuesday, April 27, 2010 9:51 AM
    Moderator
  • Hi ,

    negative values represents errors, and lookat the average its wierd.

    As a first troubleshooting , i would first upgrade the driver or replace it and check.


    What in case of HYPER-V OS.......it is virtual machine. should i do something outside in Virtual interface or just uninstal/reinstall driver inside.
    Tuesday, April 27, 2010 10:23 AM
  • Hi ,

    sorry for confusion, you can omit the above method.

    I would check few things with respect to hyper-v

    make sure the guest OS has single CPU.

    make use of /usepmtimer switch in boot.ini , you can follow the below link

    http://support.microsoft.com/kb/895980

    • Marked as answer by Tiger Li Thursday, May 06, 2010 1:55 AM
    Tuesday, April 27, 2010 1:06 PM
    Moderator
  • Hi

    Could you post the route table of the guest os?

    The virtual networks setting of this issuer guest os is same as the other guest os?

    In the guest os,do any other forms of network access work? (file sharings , web browering etc.....)

    Wednesday, April 28, 2010 8:40 AM
  • Hi

    Could you post the route table of the guest os?

    The virtual networks setting of this issuer guest os is same as the other guest os?

    In the guest os,do any other forms of network access work? (file sharings , web browering etc.....)

    Yes network setting is same as other guest OS. Yes it can access file shares from same subnet. But not other subnets as compared to other servers which can access other subnets' shares.

    Here is the route table of the guest os

    IPv4 Route Table

    ===========================================================================

    Interface List

    0x1 ........................... MS TCP Loopback interface

    0x10003 ...00 15 5d 00 7a 04 ...... Microsoft Virtual Machine Bus Network Adapte

    r #2

    ===========================================================================

    ===========================================================================

    Active Routes:

    Network Destination        Netmask          Gateway       Interface  Metric

              0.0.0.0          0.0.0.0      10.72.0.254       10.72.0.79     10

            10.72.0.0    255.255.255.0       10.72.0.79       10.72.0.79     10

           10.72.0.79  255.255.255.255        127.0.0.1        127.0.0.1     10

       10.255.255.255  255.255.255.255       10.72.0.79       10.72.0.79     10

            127.0.0.0        255.0.0.0        127.0.0.1        127.0.0.1      1

            224.0.0.0        240.0.0.0       10.72.0.79       10.72.0.79     10

      255.255.255.255  255.255.255.255       10.72.0.79       10.72.0.79      1

    Default Gateway:       10.72.0.254

    ===========================================================================

    Persistent Routes:

      None

     

    and IPconfig/all


    Z:\>ipconfig /all

    Windows IP Configuration

       Host Name . . . . . . . . . . . . : FF01
       Primary Dns Suffix  . . . . . . . : abc.com
       Node Type . . . . . . . . . . . . : Unknown
       IP Routing Enabled. . . . . . . . : No
       WINS Proxy Enabled. . . . . . . . : No
       DNS Suffix Search List. . . . . . : abc.com
                                          

    Ethernet adapter Local Area Connection 2:

       Connection-specific DNS Suffix  . :
       Description . . . . . . . . . . . : Microsoft Virtual Machine Bus Network Ada
    pter #2
       Physical Address. . . . . . . . . : 00-15-5D-00-7A-04
       DHCP Enabled. . . . . . . . . . . : No
       IP Address. . . . . . . . . . . . : 10.72.0.79
       Subnet Mask . . . . . . . . . . . : 255.255.255.0
       Default Gateway . . . . . . . . . : 10.72.0.254
       DNS Servers . . . . . . . . . . . : 10.72.0.71
                                           10.72.0.81

    Z:\>

    Wednesday, April 28, 2010 9:03 AM
  • Looks the network setting is correct..........confused.........

    Could you post a trace result here? From the guest os to the client

    have you check the 10.72.0.254 for conform there not deny 10.72.0.79 throght ?

    Also please follow the Sainath IRP_MJ_CREATEMVP's suggestion make use of /usepmtimer switch in boot.ini

    Thanks

    Friday, April 30, 2010 6:08 AM
  • Looks the network setting is correct..........confused.........

    Could you post a trace result here? From the guest os to the client

    have you check the 10.72.0.254 for conform there not deny 10.72.0.79 throght ?

    Also please follow the Sainath IRP_MJ_CREATEMVP's suggestion make use of /usepmtimer switch in boot.ini

    Thanks


    Here it is.......yeah i will try his instructions definitely as soon as i will get access to Hyper-V machine.............in the mean time, here are the tracerts

     
    Tracing route to 10.80.4.40 over a maximum of 30 hops

      1    <1 ms    <1 ms    <1 ms  10.72.0.254
      2    <1 ms    <1 ms    <1 ms  10.80.4.40

    Trace complete.

     

    Friday, April 30, 2010 8:12 AM
  • Hi Hasan-Exchanger

     

    After reading your post, I understand that you can ping same subnet hosts but other subnet.

     

    We noticed that the delay quite long and negative response when you ping local subnet host.

    It seems that this is an unexpected high latency, this issue frequently happens on hyper-v guest machine.

    Please following Sainath’s suggestion to updates the BIOS on the computer. Or, modify the Boot.ini file to use the /usepmtimer switch.

     

    In addiction here is an article for you reference

     

    A Windows Server 2003-based server may experience time-stamp counter drift if the server uses dual-core AMD Opteron processors or multiprocessor AMD Opteron processors

     

    http://support.microsoft.com/kb/938448

     

    If there is any update on this issue, please feel free to let us know.

    We are looking forward to your reply.

     

    Thanks

     

    Tiger Li

    Thursday, May 06, 2010 1:54 AM