Re: carp and routing

[Stephen Borrill <netbsd%precedence.co.uk@localhost>]

On Tue, 14 Mar 2017, Hauke Fath wrote:
> While I have many problems with workplace's carp router pair, the
> primary machine's default route is not one of them. (The fallback
> machine's default route, though, is void, which might give problems
> with ntp.)

Does it not give problems after failover?

> On Tue, 14 Mar 2017 19:15:46 +0000 (GMT), Stephen Borrill wrote:
> > default            80.x.y.62          UGS         -        -      -  carp1
>
> My box says
>
> % netstat -f inet -nr | grep 130.83.a
> default            130.83.a.b         UGS         -        -      -  wm0
> 130.83.a.b/29      link#2             UC          -        -      -  wm0
> 130.83.a.c         130.83.a.c         UH          -        -      -
> carp0
> 130.83.a.d         m:n:o:p:q:r        UHLc        -        -      -  wm0
> %
>
> here, and I seem to recall you should generally not use the carpN
> interfaces, but stick to the physical ones.

I'm guessing you have an IP address on wm0 and your carp0 address is a 
/32. I'm trying to conserve IP addresses.

My workaround for this back in the NetBSD 6 days was to statically add an 
arp entry for the router before setting up the default route. I'm sure
this worked, but since upgrading to NetBSD 7 it does not. I get 
funky-looking routes like the following on the backup machine:

80.x.y.62        c4.71.fe.65.53.61  UHS         -        -      -  carp1

--
Stephen