Which interface is used by default when performing a traceroute from a core switch?

[Jack G]

Which interface is used by default when performing a traceroute from a core switch? Is there a specific one like the MGMT interface, or does it pick the interface with the closest next hop? Just curious since it doesn't show the originating IP in the trace and just the next hop.

[Reza Sharifi]

By default, it picks the closest interface to the next hop you are tracing from.

HTH

[Jon Marshall · Accepted solution]

To be specific it consults the IP routing table to get the next hop IP for the destination IP address and then uses the source IP of the interface used to get to that next hop IP. 

Jon