[pgpool-general: 3524] Re: Amazon EC2 Load Balancer health check kills pgPool node
ishii at postgresql.org
Tue Mar 17 08:28:59 JST 2015
I guess pgpool-II complains that EC2 Elastic Load Balancer does not
disconnect the session in a grace manner. As far as I know, EC2
Elastic Load Balancer supports HTTP/HTTPS but does not support the
PostgreSQL protocol. So I think there is not too much that pgpool-II
SRA OSS, Inc. Japan
> Hi all,
> I$B!G(Bm running pgPool 3.4.1 on a pair of CentOS 6.6 boxes at AWS, and I have an EC2 Elastic Load Balancer configured to balance requests between them. I have health checks set up on the load balancer, and I$B!G(Bve noticed that every time I get a health check, the pgPool worker process that services that request dies. Here$B!G(Bs an excerpt from the log:
> pgpool: [951-2] 2015-03-16 18:14:36: pid 389: DETAIL: EOF encountered with frontend
> pgpool: [749-1] 2015-03-16 18:14:36: pid 27: LOG: child process with pid: 389 exits with status 256
> pgpool: [750-1] 2015-03-16 18:14:36: pid 27: LOG: fork a new child process with pid: 480
> pgpool: [733-1] 2015-03-16 18:15:06: pid 502: FATAL: unable to read data from frontend
> pgpool: [733-2] 2015-03-16 18:15:06: pid 502: DETAIL: EOF encountered with frontend
> pgpool: [759-1] 2015-03-16 18:15:06: pid 28: LOG: child process with pid: 502 exits with status 256
> pgpool: [760-1] 2015-03-16 18:15:06: pid 28: LOG: fork a new child process with pid: 524
> This was happening every 30 seconds. When I change the health check to be every 5 minutes, the child process dying also moved to every 5 minutes. I don$B!G(Bt have a whole lot of control over the health check $(Q#|(B it$B!G(Bs a TCP connection on the pgPool port.
> Has anybody seen something like this before?
> SCOTT RANKIN
> Vice President, Technology
> Motus, LLC
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