Can not ping one Wireless controller in Pair

[hinklw]

We have run in to a strange issue. We have 2 wireless controllers. These are on our production subnet.

From the production subnet, we can both ping and access both devices via ssh or EDM.

From other subnets we can only access device number 2.

From the core, we can ping both.

Has anyone seen this before?

[rameshng]

What model of the Controllers are these? Is this 8100 series of Controller. In that the management VLAN of your controller is changed to a different one.
The reason you may be able to ping from the Core switch is because the Core switch will have the VLAN of the management for Controller 1 and 2. This may be pinging being in the same subnet.
This definitely looks like a gateway configuration issue in the Controller 2.

[hinklw]

Thanks for the reply.

These are 8100 series. The management address is on the same subnet as the other network infrastructure.

Very strange. We can not find a difference in the configuration between the 2 controllers, but will comb through them again.

[rameshng]

I expect the issue to be either VLAN spanning issue or a proper gateway configuration issue. I don't see any other reason.