carp + mysql replication: failover

have two machines that are carped and have mysql databases
on them. one 
machine is the mysql master and the other a slave that
replicates the 
master. this keeps things ready for what i've just
experienced: mysql 
master machine goes down. now that a master failure has
occurred, i am 
not certain of the best path for bringing the master back
online so that 
it's synced with the slave.

to bring the master back online correctly i see the
following as an 
obvious, but laborious, path: (1) restart master and
increase advskew on 
the carp interface so the slave stays MASTER (2) edit config
files and 
restart mysql on both machines so that the slave is now the
master and 
vice versa for the original master (3) initiate slave
replication onto 
the original master (4 - optional) decrease advskew on the
original 
master machine so that it takes over (5 - optional)  restart
mysql on 
both machines, swapping the master and slave configs. the
optional steps 
are only if restoring the original master as master is
desired.

if there is another way to do what i've described above that
doesn't 
involve downtime for mysql or is more easily automated,
please advise.

cheers,
jake

Jacob Yocom-Piatt wrote:
> have two machines that are carped and have mysql
databases on them. 
> one machine is the mysql master and the other a slave
that replicates 
> the master. this keeps things ready for what i've just
experienced: 
> mysql master machine goes down. now that a master
failure has 
> occurred, i am not certain of the best path for
bringing the master 
> back online so that it's synced with the slave.
>
> to bring the master back online correctly i see the
following as an 
> obvious, but laborious, path: (1) restart master and
increase advskew 
> on the carp interface so the slave stays MASTER (2)
edit config files 
> and restart mysql on both machines so that the slave is
now the master 
> and vice versa for the original master (3) initiate
slave replication 
> onto the original master (4 - optional) decrease
advskew on the 
> original master machine so that it takes over (5 -
optional)  restart 
> mysql on both machines, swapping the master and slave
configs. the 
> optional steps are only if restoring the original
master as master is 
> desired.
>
> if there is another way to do what i've described above
that doesn't 
> involve downtime for mysql or is more easily automated,
please advise.
>

in case anybody else encounters a similar situation, a
friendly bird 
whistled in my ear:

http://www.onlamp.com/pub/a/onlamp/
2006/04/20/advanced-mysql-replication.html 


> cheers,
> jake