On 10-10-29 06:15 AM, Jason Chen wrote:
> Hi Steve,
>
> After more troubleshooting and several times reconfiguration whole
> system, it seems the issue should be in master node configuration.
> However, I still haven't figured out the root cause and reproduce step.
> This is not reproduced every time.
>
> In the normal correct case, after configure master node, there has
> consistent SYNC events which will be generated. However, in the error
> case, looks like master node slon has hung and there is no new SYNC
> events generated.
>
> Do you have any more insight on the potential issue which might happen
> during master node configuration?
>
> Thanks,
> Jason
>

If you turn up the logging level to debug , what does slon report in the 
log in cases where it doesn't work.   I must be logging some stuff even 
if it then stops/hangs.


slon using the connection settings from the service config to connect to 
its 'local' database that it generates the syncs on.  It sounds like 
slon isn't able to talk to this database.


>
> On Fri, Oct 29, 2010 at 11:05 AM, Jason Chen <yunfeng82 at gmail.com
> <mailto:yunfeng82 at gmail.com>> wrote:
>
>     Hi Steve,
>
>     Thanks for your response. During those 7 hours, actually I have done
>     nothing but just leave it there. The sl_path will be correctly
>     updated after that time. Another workaround to solve this issue is
>     restart master node slon service which will also update sl_path to
>     the correct value in pa_conninfo.
>
>     I have turned on the highest level log on both slon and postgresql
>     but didn't find more useful information. In the normal case,
>     pa_conninfo in sl_path will be event pending only for a short time
>     and then will be updated correctly after master generates STORE_PATH
>     event. However, in the error case, looks like master will not
>     generates STORE_PATH event.
>
>     What will be case that cause master node hangs and cannot generate
>     STORE_PATH event? Is there any more debug information I can check in
>     gdb for the slon process?
>
>     Thanks,
>     Jason
>
>
>
>     On Fri, Oct 29, 2010 at 2:05 AM, Steve Singer
>     <ssinger at ca.afilias.info <mailto:ssinger at ca.afilias.info>> wrote:
>
>         My question is what were the slons doing during those 7 hours.
>
>         If you configure your slon processes to log at the debug level
>         they should print a fair amount of stuff.
>
>         You get the <event pending> entries in sl_path when you
>         subscribe the set before processing the STORE_PATH message on
>         the other node.
>
>         What maybe want to do is move define_replication_set to come
>         after you've started up the slons.
>
>         Having said that even if you do things in the order you
>         described things still should have worked and I don't see why it
>         took 7 hours to update sl_path.  What were the slons doing
>         during those 7 hours.
>
>
>