Question about very strange routing problem

From: Reed, Judith (jreed_at_navisite.com)
Date: 03/23/04

  • Next message: Reed, Judith: "Question about very strange routing problem - update with ifconfig/arp/netstat output" 
    Date: Tue, 23 Mar 2004 11:03:17 -0500
To: tru64-unix-managers@ornl.gov

    We have a set of 8 servers, all running tru64 v5.1a, pk2. They are all
    connected to multiple nets, but all share a common net as well:

    Server1 server2 server3 server4 server5 server6 server7 server8
        | | | | | | | |
    ----------------------------------------------------------------

    server1/server2/server3 can all reach server8 and vice-versa.

    server4/server5/server6/server7 can *NOT* reach server8, nor can server8
    reach them.

    server4/server5/server6/server7 can reach server1/server2/server3 and
    vice-versa.

    server1->server7 all know to go out the shared network to reach server8.

    server8 knows to go out the shared network to reach server1->server3,
    but tries to go out a different default route to reach server4->server7,
    even when responding to pings/ssh/tcpdump packets coming in the shared
    common network from the problematic servers.

    server8 also knows the correct MAC address of *all* the servers on the
    shared common network, and the correct IPs associated with those MAC
    addresses.

    There is nothing odd in /etc/routes or "netstat -r" output on *any* of
    the servers, either the ones that *can* communicate or those who
    *cannot*.

    I'm baffled. If this wasn't a prod env. I'd reboot the d*mn server8, but
    that's not an option. Anyone have any suggestions/insights???

    Regards,

    Judith Reed
    jreed@navisite.com
    Service delivery manager, Syracuse Data Center
    315-453-2912 x5835

  • Next message: Reed, Judith: "Question about very strange routing problem - update with ifconfig/arp/netstat output"