[Pgpool-general] Clarifying interaction between master/slave mode and automated failover [SumsaultRT #3219]

[Mark Stosberg]

Hello,

Thanks for your work on pgpool. I'm currently researching using it in conjunction with Slony-I
for load-balancing.

I'd like to clarify some points from the documentation:

 1. No automated failover will happen unless "health_check_period" is set. Correct?
    Another parts of the documentation indication that failover is
	automatic rather than that it /can be/ automatic.

 2. What's the behavior when failing over from master to slave? Does it 
    still continue to send only SELECTs to the slave, or does it began
	to treat it as a master? 

I would like for pgpool not to start treating the slave the master,
because I'm afraid that could mess things up if there is a network
blimp, but the Slony-I master/slave replication is working OK.  

This part of the switchover documentation could be clearer:

   $ pgpool [-f config_file] [-s {m[aster]|s[econdary]] switch

   If [-m {s[mart]|f[ast]|i[mmediate]}] part is omitted, master goes
   down. To stop secondary try:

   $ pgpool [-f config_file] -s s[econdary] switch

It says "If [-m {s[mart]|f[ast]|i[mmediate]}] ...", but those options
aren't included in the example above it. 

My guess is that:

 # turn off the master
 $ pgpool -s master switch

 # turn off the secondary (possibly a slave)
 $ pgpool -s secondary switch

Is that correct? 

Thanks!

	Mark