wrong device detection

[zh99998]

if server has many devices with same ip address, tcptraceroute auto select device will be wrong.

# tcptraceroute 10.8.0.1 -f 30
Selected device railgun1, address 10.3.0.1, port 33989 for outgoing packets
Tracing the path to 10.8.0.1 on TCP port 80 (http), 30 hops max
30  * * *
Destination not reached

there is an example that the server has many devices named railgun*, all of them local address is 10.3.0.1, and routed by destination address

10.1.0.0/16 dev railgun1  proto kernel  scope link  src 10.3.0.1
10.2.0.0/16 dev railgun2  proto kernel  scope link  src 10.3.0.1
...
10.8.0.0/16 dev railgun8  proto kernel  scope link  src 10.3.0.1

all my applications, including ping, traceroute, and production services works well with this routing. except tcptraceroute auto select wrong device.

    if (device == NULL)
        /* not specified on command line */
        device = finddev(recommended_src);

the proper way is detect it by route table.

i know tcptraceroute could specific device name from command line. but i'm not calling tcptraroute manually, and using some automatic cluster management tools, which can't specific different parameters for each server and each target.

[zh99998]

closing this since long time inactive