Catalyst 1000 Switch Configuration Issue

[AndyClark]

Let me start with a few sorry's.

1. Sorry, I'm NOT an IT person and therefore don't know the lingo nor am I well versed in the details of the questions I'm about to ask. I am posting here because our actual IT person struggled with these issues today and I'm hoping to garner some things to try to resolve the problem.

2. Sorry if this has been asked and answered 100 times. I tried a few searches and wasn't able to find this specific problem...likely because I DON'T know the proper terminology, etc.

OK, here goes. I act as my companies internal "IT Guy". I keep workstations up and running, set up new workstations, basic networking stuff, etc. When you start talking detailed IP addresses, subnets, IPV...you've lost me. Here's what we went through today and the problem we encountered along the way. I installed 2 C1000-8P switches each with a C145 WAP. I had traffic across the network and through the WAPs but never configured the switches through the Day0 Wizard and never handed out the WiFi keys to anyone for lack of proper configuration. I wanted our actual IT guy to come and configure everything properly before making this portion of the network accessible to anyone.

OK, so our IT guy shows up and starts digging in and figures out how to get into the Day0 Wizard interface. We want a separate VLAN for our guest WiFi network so he sets everything up as he thinks is appropriate and finishes the wizard. Our main Firewall (Fortigate) is set to 10.0.0.1 so he set the switches management interface up in the next available IP at 10.0.0.5 with a default gateway of 10.0.0.1. We were able to log in to the management interface at 10.0.0.5 and finish configuring the switch and everything seemed fine. All of the sudden, all of the users on our primary network get booted offline. After some digging, we found that the switch was still trying to operate on 10.0.0.1 even though the interface was accessible through 10.0.0.5. We tried setting the Management Interface IP to 10.0.0.5 manually on the Switch Configuration page and it appeared to accept the changes ("settings saved successfully" popup would appear in the bottom right), but after the page refreshed it would still say 10.0.0.1 in that field and the switch would continually boot everyone offline every couple of minutes when connected to the rest of the network. Connecting through the CLI, our IT guy was able to see the 10.0.0.1 "secondary" IP address but couldn't figure out how to force it to change while he was on-site. I gave him a brand new identical switch to take back to his office to work with to try to figure things out but this seems like a problem we should not be having. It feels like we're doing something simple, wrong. Does anyone with experiance setting up the Catalyst 1000 switches know what we might be doing wrong or what to try to figure out why the switch keeps wanting to operate on 10.0.0.1?

[Torbjørn · Accepted solution]

HI @AndyClark,

You can remove the secondary ip address by executing the following commands in the CLI:

enable
configure terminal
interface vlan { vlan number }   ! Your IT guy should ble able to provide the correct number
no ip address 10.0.0.1 255.255.255.0 secondary
end
write

You should be able to access the CLI by attaching to the switch using mini-USB and opening a serial session in Putty and connecting to "COM3".

[AndyClark]

It took a long time to get back around to this issue, but this worked to solve the issue! I wish Cisco had considered this situation and allowed the GUI on these switches to properly update the secondary IP address directly.

[AndyClark]

Reviving this thread with a slightly different issue, but 100% related to the original question. I have a new Catalyst 1000 48 port switch to replace an old one that doesn't meet our requirements. I am doing the above steps to remove the conflicting IP address but the CLI returns,

"IP address conflicts with gateway ip address in static routing table"

Which is EXACTLY the problem I'm trying to eliminate. Why, when trying to remove the 10.0.0.1 SECONDARY IP address, would it tell me that there is a conflict with the gateway IP?

[Richard Pidcock]

@Torbjørn has suggested a good way to remove the secondary addressing.  If you don't have success with that, perhaps you could share your config and we can review in more detail to provide guidance.