[pgpool-general: 2021] Re: Problem with watchdog...

[Tatsuo Ishii]

> On 08/05/13 14:07, Fernando Buzon wrote:
>>
>> FINAL:
>> Like I said, all is working nice.
>> And now I am with the 2 pgpools up and working again.
>> The escaled pgpool is pgpool-01.
>> I stop it with "killall -9 pgpool" and now wd_lifecheck worked fine on
>> pgpool-02!
>> I dont now what was the problem early, but now is working!
>>
> 
> Maybe you fix some small issue in the config during your testing.
> 
>> log on pgpool-02:
>> 2013-08-05 17:52:42 LOG:   pid 11524: wd_lifecheck: lifecheck failed 3
>> times. pgpool 1 (10.0.0.21:5432 <http://10.0.0.21:5432>) seems not to be working
>> 2013-08-05 17:52:42 LOG:   pid 11524: wd_escalation: escalated to master pgpool
>> 2013-08-05 17:52:42 LOG:   pid 11524: wd_escalation:  escalated to
>> delegate_IP holder
>> 2013-08-05 17:52:52 LOG:   pid 11524: wd_lifecheck: lifecheck failed 3
>> times. pgpool 1 (10.0.0.21:5432 <http://10.0.0.21:5432>) seems not to be working
>>
>> So rest only one problem, that is how to down delegate_ip from the pgpool-01?
>> Because both servers is responding to delegate_ip.
> 
> Well, the reason it doesn't get removed on pgpool-01 is because the killall -9
> kills the pgpool processes including the watchdog without any hope of them
> running the ifconfig down command.
> 
> That said, you just need to run the ifconfig down command on pgpool-01.
> 
> I'm sure what you're trying to simulate is a crash, but I'm not sure killing
> ALL the pgpool processes with -9 is a good simulation, because more likely
> only one of the backends would crash.
> 
> Maybe one of the other folks on the list can suggest a better simulation for a
> crashing pgpool service.

I have tried with pgpool-II 3.3.0 to test the case. Initially
"server2" is the watchdog active, and "server1" is the watchdog
"standby".

I killed server2 pgpool-II parent process by kill -9.

- server2 releases the VIP. server2 watchdog goes to "down" status.

- server1 becomes active and grab the VIP.

So my guess is, 3.2's watchdog is not capable to handle the situation.

Pgpool-II 3.3's watchdog is much more enhanced than 3.2's. I recommend
to use 3.3 if you want to seriously use watchdog.
--
Tatsuo Ishii
SRA OSS, Inc. Japan
English: http://www.sraoss.co.jp/index_en.php
Japanese: http://www.sraoss.co.jp