On 2017-05-19, Gregory Edigarov <[email protected]> wrote: > Hi, everybody > > I've run into a strange problem while trying to implement cisco's 'ip > sla' replacement for a customer. > > at an openbsd router i have > > em0: 192.168.0.1/24 - local network > > em1: 111.111.111.2/30 - uplink 1 > > em2: 222.222.222.2/30 - uplink 2 > > ip forwarding is on, routes received via bgp, everything work as expected. > > the only problem is when something happens deep inside uplink's network: > > sessions stay up, routes still present, but no traffic can pass though > uplink. > > BFD would help, may be, but I stick to what i have right now. > > I am trying to > ping -I 111.111.111.2 8.8.8.8 > > but get no answer, because route to 8.8.8.8 set through uplink2, furthermore > > i see my pings on em2 with tcpdump which seems rather strange to me, as > I am enforcing the interface. > > if i ping 8.8.8.8 the normal way "it works" (tm). > > pinging with -I 222.222.222.2 works too. > > so ? > > perhaps I am overlooking something very-very basic, so help me to get > off the brake.
ping -I doesn't enforce the interface, all it does is set the source address. You could enforce with a PF route-to rule if you like.
