I'm in the process of setting up a 9.1-based SR cluster, and I've got a 
question on how failover is expected to work in the case of multiple slaves. 
http://www.postgresql.org/docs/9.1/static/warm-standby-failover.html says:

"Some people choose to use a third server to provide backup for the new primary 
until the new standby server is recreated, though clearly this complicates the 
system configuration and operational processes."

I think a third server sounds like a swell idea, but I'm unclear how a slave 
based on the old master can act as a slave for the new master. I thought that 
once the master switched, you'd get a new wal timeline, and any existing slaves 
won't follow along with the new timeline. Which is really unfortunate, because 
it means the only way to have a slave, immediately after a failover, is to 
build one ASAP and hope you don't have insurmountable problems while that's 
going on. For a big database, that can take a while.

Hopefully I'm missing something?

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