question regarding multilayer switch routing

[Joshua Engels]

I have a 4510 as my core switch. I have noticed during trace routes that sometimes an SVI might be involved in the routing that is not in the network path. For example, I may be on network with the SVI of 192.168.1.1 and I am pinging a system on another network with the SVI of 10.4.4.1/24. I notice in the process that one of the hops is for another network SVI of 172.16.16.1. All three of these networks have SVI on the core switch. Why would 172.16.16.1 show up as a hop in the trace?

Sent from Cisco Technical Support iPad App

[Julio Carvajal]

Hello Joshua,

You mean doing a traceroute you could see that inbetween??

That should not happen unless there is a desing issue,

Can you post a  topology of your network and from where to where are you trying to go as what you are saying should not happen

Hope I could help.

Remember to rate all of the helpful posts

Julio

[Joshua Engels]

Let me try and clarify:

So here is what I see when I do a Trace route from my PC.  My IP address is 192.168.99.100.

My Core switche contain an SVI for each network.  Below are the SVI's for each network along with the switchport that connects the WAN.

interface vlan4

ip address 10.4.4.1 255.255.255.0

interface vlan30

ip address 192.168.30.1 255.255.255.0

interface vlan 99

ip address 192.168.99.1 255.255.255.0

interface g4/1

no switchport

ip address 172.17.17.2 255.255.255.252

(Interface g4/1 is a WAN connection to the network where esxcom1 lives.  (192.168.174.20))

See my Trace route below:  Why am I seeing 192.168.30.1 in the trace?

C:\>tracert 192.168.174.20

Tracing route to esxcom1.community.com [192.168.174.20]

over a maximum of 30 hops:

  1    <1 ms    <1 ms    <1 ms  192.168.99.1

  2    <1 ms    <1 ms    <1 ms  192.168.30.1

  3     1 ms     1 ms     1 ms  172.17.17.2

  4     1 ms     1 ms     1 ms  esxcom1.community.com [192.168.174.20]

Trace complete.