You can use Loose Source Routing to achieve this. It allows you to specify a mandatory hop that has to be traversed by the traceroute. Here's how you can do it:
r4#traceroute
Protocol [ip]:
Target IP address: 10.10.10.1
Source address: 192.168.14.4
Numeric display [n]: y
Timeout in seconds [3]:
Probe count [3]:
Minimum Time to Live [1]:
Maximum Time to Live [30]:
Port Number [33434]:
Loose, Strict, Record, Timestamp, Verbose[none]: L
Source route: 192.168.23.1
Loose, Strict, Record, Timestamp, Verbose[LV]:
Type escape sequence to abort.
Tracing the route to 10.10.10.1
So in you case, you could specify the nexh-hop address for the GW you want the packet to use.
Hope this helps,
Harold Ritter
Sr Technical Leader
CCIE 4168 (R&S, SP)
harold@cisco.com
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