Cisco 2960X set its' own gateway

[c.duck]

I have several 2960x series switches with IP routing turned off and the IP default-gateway command entered into them.

IP default-gateway 10.1.1.254

However, they will auto-magically define their own routes to certain clients on a remote network i.e.

VLAN for the switch is 

10.1.1.252

The remote network is 

10.2.2.0/24

Client A is

10.2.2.1

Client B is

10.2.2.2

Listing a sh IP route on the switch shows that the route for Client A is not listed (and is accessible) but for Client B (and is not accessible) it is using a route of 10.1.1.252 to get to Client B which is not a gateway device and is not defined anywhere in the configuration. Has anyone seen this or have any ideas as to why the switch is defining its' own route to a client?

[Georg Pauwen]

Hello,

weird indeed. Can you post the output of:

sh run

sh ip route

[Reza Sharifi]

Can you post the output of "sh ip route"?

HTH

[c.duck]

Here is the sh ip route I do not feel comfortable posting a full running-config on a forum though and the IPS have been changed here to protect the innocent.

AI17-SW2#sh ip route

Default gateway is 10.1.1.254

Host               Gateway           Last Use    Total Uses  Interface

10.2.2.1      10.1.1.253        0:00         18104  Vlan1

10.2.2.3   10.1.1.253           727  Vlan1

10.2.2.4     10.1.1.253        0:03         13591  Vlan1

[Reza Sharifi]

Is 10.1.1.254 a router or switch? Is it up, running, and pingable?

This may be a bug. You may want to delete the default gateway on one of the switches and redo it and test.

If that does not work, the other thing you can test is to remove the default gateway, turn on IP routing and add an IP route command and see if there is a difference.

HTH

[c.duck]

10.1.1.254 is a router and is pingable and routing the traffic for the switch as the default-gateway.

[Reza Sharifi]

You only have one IP on the switch and that is the IP address for the SVI for vlan1, right?

"sh run int vlan1" should show ip 10.1.1.253

Also, can you issue "sh ip int brief" and see the SVI for vlan1 is in up and up mode and there is no other ip on the switch?

Also, how does the switch connects to the router? Is that an access port or trunk port?

HTH

[c.duck]

• Yes the VLAN shows 10.1.1.253
• sh ip int brief only list the one IP assigned to VLAN1
• Directly connected to the router via a TRUNK interface