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Weird IP Addressing Issue

I have workstations on network x accessing servers on network y, for some reason a couple workstations on network x aren't able to access servers on network y and all workstations on network x are configured and installed exact same way. The weird thing is that if I change the IP address on the workstation that was having issue to a different IP address on network x then all works fine and there is no ACL between two networks. And all switchports connecting all workstations on network x are configured the same.

And another weird thing is that if I take the original IP address that was assigned to the workstation that was having issue and assign it to a known working workstation then that workstation will have the same issue.

Can someone help explain why this happens !!!

Thank you in advance !!!



Re: Weird IP Addressing Issue


Sounds like possibly a duplicate IP address issue. Ping the non-working address from the gateway router and check the ARP entry. Compare the MAC to check whether a duplicate address exists.




Re: Weird IP Addressing Issue

I Think you'll find that, in addition to the symptoms you describe, if you disconnect the host from the switchport (unplug it) and either move it to another port, or wait a while and plug it back into the same port, the Host will recover the connection.

Just guessing here .... but it wouldn't happen to be a 2950 switch, would it?

I think the last time I saw anything on this, the recommended course of action was to update the IOS.

Other things to check would be things like Duplex mismatch, excessive broadcasts, excessive collisions etc .... check the interfaces stats.

Good Luck