lo is up, but can't route through it

[falling]

This problem popped up out of nowhere a few weeks ago, I guess because of the automatic nightly yum updates. (Note to self....)

ifconfig shows that lo is up, but route has no listing for it, and when I try to add a route it gives an error:

[2259][/tmp]# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
10.0.0.0        *               255.255.255.0   U     0      0        0 eth0
169.254.0.0     *               255.255.0.0     U     0      0        0 eth0
default         10.0.0.1        0.0.0.0         UG    0      0        0 eth0

[2259][/tmp]# route add -net 127.0.0.0
SIOCADDRT: Invalid argument

Googling for that error hasn't helped at all yet; it seems to be a pretty generic error, and my route arguments are directly from the localhost example in the manpage, so I doubt they're invalid.

Any ideas?

Thanks,
Anthony DiSante
http://nodivisions.com/

[macemoneta]

The error you're getting is because of the syntax error in the route statement. You want:

route add -net 127.0.0.0 netmask 255.0.0.0 lo

There's an open bug on the issue, but the loopback route may not be needed anymore.

[falling]

Originally Posted by macemoneta

The error you're getting is because of the syntax error in the route statement. You want:

route add -net 127.0.0.0 netmask 255.0.0.0 lo

There's an open bug on the issue, but the loopback route may not be needed anymore.

Wow, a blatant error in the route manpage. I never would have guessed that. It definitely says that the way to add the default loopback device is "route add -net 127.0.0.0". Thanks for letting me know.

-Anthony DiSante
http://nodivisions.com/