[Pgpool-general] pcp_attach_node problem?

Tue Jan 20 23:46:27 UTC 2009

I think the patch is for debugging purposes, but I'm not sure.

The weird thing that happens to me is the following (I just tested it
again):

1. The two backends start
2. start pgpool. So both backend statuses are 2.
3.a stop primary backend,
    The connection is lost with the message "server closed the
connection unexpectedly
        This probably means the server terminated abnormally
        before or while processing the request.
The connection to the server was lost. Attempting reset: Succeeded.",
every time I try to re-run the query.
    If I re-attach the primary backend, the connection works just fine
again.
3.b stop secondary backend.
    The connection keeps going (good).
    If I re-attach the primary backend, the connection blocks.

It's weird

Daniel

> -----Original Message-----
> From: Marcelo Martins [mailto:pglists at zeroaccess.org] 
> Sent: Tuesday, January 20, 2009 6:03 PM
> To: Crespo, Daniel @ SDS
> Cc: pgpool-general at pgfoundry.org
> Subject: Re: [Pgpool-general] pcp_attach_node problem?
> 
> yeah just saw your new one when sent mine :)
> 
> weird  that it just keeps throwing that error.
> I think I have done the PG shutdown and then re-attaching about 15  
> times now and I only get the "server closed the connection  
> unexpectedly" once.
> 
> I haven't tried to apply the patch that Tatsuo mentioned on 18th  
> though to see what difference it makes. might try that today
> 
> 
> Marcelo
> PostgreSQL DBA
> Linux/Solaris System Administrator
> 
> On Jan 20, 2009, at 4:52 PM, Daniel.Crespo at l-3com.com wrote:
> 
> > Hi, Marcelo,
> >
> > I just wrote to the mail list something about exactly this.
> >
> > In your description, it doesn't happen to me... I don't know why...
> > After doing failover, when a query is executed it throws back that
> > "server closed the connection unexpectedly", and keeps 
> throwing that  
> > for
> > every try I make. No idea about this.
> >
> > Thanks for the information!
> >
> > Daniel
> >
> >> -----Original Message-----
> >> From: Marcelo Martins [mailto:pglists at zeroaccess.org]
> >> Sent: Tuesday, January 20, 2009 5:34 PM
> >> To: Crespo, Daniel @ SDS
> >> Subject: Re: [Pgpool-general] pcp_attach_node problem?
> >>
> >> Hi Daniel,
> >>
> >> I have just tested that with pgpool 2.1 and I also have the
> >> same issue.
> >> When I re-attach node 1 (second node) back, the psql
> >> connection that I
> >> had opened hangs  after executing a second query.
> >>
> >>  ERROR: pid 31003: pool_read2: EOF encountered with backend
> >>
> >> On the latest CVS version though the hanging issue seems 
> to be fixed.
> >> Now when the failover/failback happens though it seems like pgpool
> >> failover_handler process kills the childs that pgpool had open with
> >> node 1 (second node - at least that is what I can tell from what I
> >> see ) therefore when a query is executed it throws back 
> that "server
> >> closed the connection unexpectedly" . When I execute the query a
> >> second time then pgpool uses a new child that has connection
> >> opened to
> >> node 0 "new_connection: skipping slot 1 because backend_status = 3"
> >>
> >>
> >> Marcelo
> >> PostgreSQL DBA
> >> Linux/Solaris System Administrator
> >>
> >> On Jan 13, 2009, at 8:18 AM, Daniel.Crespo at l-3com.com wrote:
> >>
> >>> Sorry for the delay, I haven't had enough time.
> >>>
> >>>> 1. Show us the logs. Full logs, but only the relevant
> >> parts (got tons
> >>>> of things to read every day here). :)
> >>>
> >>> I'll try it again with full logs to give them to you guys
> >>>
> >>>> 2. Check whether PostgreSQL is having some problem of some sort
> >>>> before
> >>>> blaming it on pgpool-II. Can you run the same queries on 
> both nodes
> >>>> and get the same results?
> >>>
> >>> PostgreSQL is not having any problems. It's not a query problem.
> >>> When I
> >>> install the latest CVS head, what I showed to you is what happens.
> >>> However, when I uninstall it and install the 2.1 released
> >> version, it
> >>> doesn't happen anymore. The problem with this 2.1 release 
> is that it
> >>> doesn't keep the connection when a node is detached or
> >> attached (if I
> >>> have an already opened connection and do attach/detach node, it
> >>> locks. I
> >>> must disconnect and reconnect in order to keep doing
> >> queries). Another
> >>> problem is that I need the insert lock newly introduced to
> >>> automatically
> >>> apply on serial fields tables.
> >>>
> >>>> 3. Check permissions in both bg_hba.conf files.
> >>> No problem with this.
> >>>
> >>>> 4. Have you considered using version 8.3.5 of PostgreSQL
> >> and see how
> >>>> it goes? Or at least, the last revision of the 8.1 branch.
> >>> No. I can not update PostgreSQL. I'm using 8.2.1.
> >>>
> >>> When I have the logs, I'll post them for sure. Thanks!
> >>>
> >>> Daniel
> >>>
> >>>
> >>>> -----Original Message-----
> >>>> From: pgpool-general-bounces at pgfoundry.org
> >>>> [mailto:pgpool-general-bounces at pgfoundry.org] On Behalf Of
> >>>> Jaume Sabater
> >>>> Sent: Friday, January 09, 2009 2:32 AM
> >>>> To: pgpool-general at pgfoundry.org
> >>>> Subject: Re: [Pgpool-general] pcp_attach_node problem?
> >>>>
> >>>> On Thu, Jan 8, 2009 at 10:14 PM,  
> <Daniel.Crespo at l-3com.com> wrote:
> >>>>
> >>>>>      And issue a SQL Select command on a table, like:
> >>>>>          postgres=# select * from pg_stat_activity ;
> >>>>>
> >>>>>  It returns:
> >>>>>  postgres=# select 1;
> >>>>>  server closed the connection unexpectedly
> >>>>>      This probably means the server terminated abnormally
> >>>>>      before or while processing the request.
> >>>>>  The connection to the server was lost. Attempting reset:
> >>>> Succeeded.
> >>>>>
> >>>>>  postgres=# select 1;
> >>>>
> >>>> Some ideas:
> >>>>
> >>>> 1. Show us the logs. Full logs, but only the relevant
> >> parts (got tons
> >>>> of things to read every day here). :)
> >>>> 2. Check whether PostgreSQL is having some problem of some sort
> >>>> before
> >>>> blaming it on pgpool-II. Can you run the same queries on 
> both nodes
> >>>> and get the same results?
> >>>> 3. Check permissions in both bg_hba.conf files.
> >>>> 4. Have you considered using version 8.3.5 of PostgreSQL
> >> and see how
> >>>> it goes? Or at least, the last revision of the 8.1 branch.
> >>>>
> >>>> -- 
> >>>> Jaume Sabater
> >>>> http://linuxsilo.net/
> >>>>
> >>>> "Ubi sapientas ibi libertas"
> >>>> _______________________________________________
> >>>> Pgpool-general mailing list
> >>>> Pgpool-general at pgfoundry.org
> >>>> http://pgfoundry.org/mailman/listinfo/pgpool-general
> >>>>
> >>> _______________________________________________
> >>> Pgpool-general mailing list
> >>> Pgpool-general at pgfoundry.org
> >>> http://pgfoundry.org/mailman/listinfo/pgpool-general
> >>
> >>
> 
> 