[Pacemaker] findif.sh

[Andrew Beekhof]

Howdy,

Could we get some documentation for findif.sh?
Specifically what should and shouldn't work.

I'm seeing various behaviour and its not clear to me whether the results are intended or not.


My eth0:
    inet 192.168.122.101/24 scope global eth0
    inet6 fe80::5054:ff:fee8:c8a7/64 scope link 

[root at pcmk-1 ~]# ip -o -f inet route list match 192.168.122.101/32 scope link
192.168.122.0/24 dev eth0  proto kernel  src 192.168.122.101 
[root at pcmk-1 ~]# ip -o -f inet route list match 192.168.122.102/32 scope link
192.168.122.0/24 dev eth0  proto kernel  src 192.168.122.101 

so far so good.  floating IPs are often on a different subnet though:

[root at pcmk-1 ~]# ip -o -f inet route list match 192.168.123.102/32 scope link
[root at pcmk-1 ~]# 

Nothing, at which point findif bails out.
Perhaps we cant exclusively rely on 'ip route list match'?
Pretty sure this used to work but I could be wrong.

Interestingly, it works if we drop the 'scope link'

[root at pcmk-1 ~]# ip -o -f inet route list match 192.168.123.102/32
default via 192.168.122.1 dev eth0  proto static  metric 1024 

Loopback addresses also don't produce anything useful which I found surprising:

[root at pcmk-1 ~]# ip -o -f inet route list match 127.0.0.2/32 scope link
[root at pcmk-1 ~]# ip -o -f inet route list match 127.0.0.1/32 scope link
[root at pcmk-1 ~]# ip -o -f inet route list match 127.0.0.1/8 scope link
[root at pcmk-1 ~]# 

But again, dropping 'scope link' seems to work.

[root at pcmk-1 ~]# ip -o -f inet route list match 127.0.0.2/32
default via 192.168.122.1 dev eth0  proto static  metric 1024