We've been having a strange routing problem with our 2 NetApps for the past month or so in which the NetApps cannot ping the Cisco router on their subnet (their default route). We have a F740 running 5.2.3 and a F540 running 5.1.2R2 and both are having this problem. The NetApps can also not ping (or connect with any other IP protocol) other hosts on other subnets. However, if a packet crosses the router to a host that the NetApp previously could not reach, then that host becomes reachable for a while. Other hosts on the same subnet as the NetApps do not have this problem, they can ping the router and other hosts on other subnets. However, the Cisco 2924 switch that the NetApps and other hosts are connected to also shows this same behavior. This has led us to suspect a problem with the Cisco switches or router, but we have pretty much eliminated any hardware problems. We have an interesting bridge-group configuration on the router to allow Sun Autoclients to boot from their server which is 1 hop away, and are also using Cisco Hot Standby Router protocol so it could be a weird interaction of these protocols that is confusing the 2924 switch. Still, why are the NetApps the only hosts that seem the be bothered?
The problem was causing "NFS server not responding" incidents lasting for up to 10+ minutes on our clients that were 1 router hop away from the NetApps until I wrote a script that runs on a Sun that pings all of these clients once a minute. There were no clues in the NetApps' or clients' logs.
Has anyone else ever seen a situation like this where the Netapp could not ping its default router?
Does anyone have any advice about using NFS across routers that can minimize or prevent the pauses that we observe on our clients?
Thank you,
Mike