Re: CARP not balancing automatically


On Oct 23, 2006, at 1:50 PM, Max Laier wrote:

Until I perform this manual step, all traffic goes to the single box.
After I perform this step, the traffic is balanced nicely as expected
amongst the local network hosts. Each box then has one MASTER and
one BACKUP carp interface for this IP.

Sounds like you forgot the net.inet.carp.preempt sysctl. See the begining
of the EXAMPLES section of carp(4).

But I don't have multiple interfaces that all need to go up/down together. I need one carp interface to be master and one backup on box A, and the opposite master/backup on box B. Or am I totally misunderstanding with the preemtp sysctl is for?

The second example in the EXAMPLES section is what I followed. It makes no mention of needing preempt, but does say I need arpbalance.

Is the documentation incomplete in the second example, then?

What I want to end up with (and what I get after my manual manipulation) is this:

one host:

carp0: flags=49<UP,LOOPBACK,RUNNING> mtu 1500
inet 192.168.100.100 netmask 0xffffff00
carp: BACKUP vhid 5 advbase 1 advskew 100
carp1: flags=49<UP,LOOPBACK,RUNNING> mtu 1500
inet 192.168.100.100 netmask 0xffffff00
carp: MASTER vhid 6 advbase 1 advskew 0


other host:

carp0: flags=49<UP,LOOPBACK,RUNNING> mtu 1500
inet 192.168.100.100 netmask 0xffffff00
carp: MASTER vhid 5 advbase 1 advskew 0
carp1: flags=49<UP,LOOPBACK,RUNNING> mtu 1500
inet 192.168.100.100 netmask 0xffffff00
carp: BACKUP vhid 6 advbase 1 advskew 100


what happens on boot is one box has both MASTER and the other has both BACKUP resulting in zero load balance.

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