Strange problem

[mike-banks]

All the host on my remote network 208.15.57.0 were able to ping the host on my local network 172.16.20.0. Now for some reason host 208.15.57.25 cannot ping host 172.16.20.3. Host 208.15.57.25 can ping any other address except 172.16.20.3. The problem is IP related because if I configure another host for 208.15.57.25 it cannot ping 172.16.20.3 either.

Has anyone seen a problem like this?

Thanks,

Mike

[amedwards]

Off the top of my head it sounds like an access list issue... have you recently activated any access lists? Look at the 172.16.20.3 host ability to ping other devices on its subnet and remote subnets and look at the 172.16.20.3 host for services it runs (e.g. firewall software, etc) that might be an issue.

If that doesn't help, post your configs and I'm sure you can get additional help from me or others...

[mike-banks]

There are no access-list in the routers and no changes have been made. This was working for months and now this one IP address (208.15.57.25)is getting request time outs whenever it tries to ping 172.16.20.3.

[kspinks]

This could be an ARP issue as well. You may want to try to clear out the arp cache (clear arp) and try again. This would likely be the case in the event you changed a NIC or replaced one of the devices outright. If this is not the case, have there been any config changes on either machine??

[pwwiddicombe]

Can other hosts on the 208.15.75 network get to 172.16.20.3?

If you do a traceroute, do you get the expected path to 172.16.20.3? I have seen this recently, where one remote router had a static route to NULL for a specific host (to avoid bringing up a dialer interface based on a floating static route). All traffic destined for the host was then directed to THAT router to be tossed out....

[mike-banks]

If I do a traceroute I do get the expected path to 172.16.20.3. It seems as though host 172.16.20.3 has decided not to respond to the icmp request from this one host.

[j.chenevey]

is there a valid entry in the arp cache for the 172.16.20.3 host? if so can you ping from it to other devices? there may be a default gateway or subnet mask misconfiguration on that host.