Here's a wierd one...
I'm in the process of renumbering the LAN.
I've got two VLANs that can talk to each other.
I have 3 3725 switches (stackwise) with about 5 2960 switches uplinking to the 3725s.
These 2960s connect to ports on the 3725 that are in VLAN10, the new network, lets say.
Below the 2960s I have many old Netgear switches uplinking to the 3725s.
These Netgears connect to ports on the 3725 that are in VLAN128, the old network.
I've been adding 2960s to VLAN10 ports and just repatching the user pcs from the old Netgears to the new 2960s.
Thus, anyone connecting to VLAN10 will be on the new network(AD) with a new IP, and this has been working just fine.
But this week, I repached a whole Netgear into a new 2960 and EVERYTHING went wrong.
It affected various PCs, not just the ones taht I moved to the Cisco 2960. Specifically, all pcs on the old network.
E.G. a PC connected to an old Netgear suddenly had an IP coming from the new network, but it's physically connected to VLAN128 and not VLAN10!
I did a sh ip arp<IP address of PC> on the 3725, it came up saying it was in Interface: VLAN10, but it's in VLAN 128...
Does anyone have any clue or idea as to what I can do to get this right?
At the moment, I'm giving the problem pcs a static IP in of the old IP range until I repatch them into the new 2960s.
I'm out of ideas...please help..anyone?