[pgpool-general: 1972] Re: pgpool 3.2.5 watchdog ifconfig down always hangs

[Yugo Nagata]

Hi,

On Fri, 26 Jul 2013 07:48:46 -0700
Jeff Frost <jeff at pgexperts.com> wrote:

> Yes, you can see the pgpool processes stuck in my ps output below.
> 
> They happily exit once I kill -9 the sudo process.
> 
> I'll see if I can get some stack traces but if you can't reproduce on Ubuntu or CentOS, I suspect it's something with Debian Squeeze's sudo or ifconfig commands.

I succeeded to reproduce it using Debian Squeeze (6.0.6).

I think, this would be a bug of sudo command and this is fixed in 1.7.5 and 1.8.0.

http://blog.famzah.net/2010/11/01/sudo-hangs-and-leaves-the-executed-program-as-zombie/
http://www.gratisoft.us/bugzilla/show_bug.cgi?id=447

My Ubuntu's version is 12.01 and the sudo version is 1.8.3p1, so there are 
no problems. However, Debian Squeeze's sudo version is 1.7.4p4

You can download the latest sudo from here:
http://www.sudo.ws/sudo/dist/

I downloaded and compiled 1.8.7 on Debian 6.0.6, and this works well.

> 
> On Jul 26, 2013, at 3:24 AM, Yugo Nagata <nagata at sraoss.co.jp> wrote:
> 
> > Hi,
> > 
> > Does pgpool hang as well as ifconfig when it is stopped?
> > I cannot reproduce this on CentOS and Ubuntu. Both pgpool and 
> > ifconfig stops normally.
> > 
> > Could you please provide me the stack trace of hanging pgpool and
> > log msessages?
> > 
> > 
> > On Thu, 25 Jul 2013 09:56:36 -0700
> > Jeff Frost <jeff at pgexperts.com> wrote:
> > 
> >> This seems to be the same on 3.2.3, 3.2.4 and 3.2.5.
> >> 
> >> The watchdog section of pgpool.conf looks like this:
> >> 
> >> use_watchdog = on
> >> delegate_IP = '10.100.2.72'
> >> wd_hostname = '10.100.2.70'
> >> wd_port = 9000
> >> ifconfig_path = '/usr/bin'
> >> arping_path = '/usr/bin'
> >> if_up_cmd = 'sudo ifconfig eth0:1 $_IP_$ netmask 255.255.255.0 up'
> >> if_down_cmd = 'sudo ifconfig eth0:1 $_IP_$ netmask 255.255.255.0 down'
> >> arping_cmd = 'sudo arping -U $_IP_$ -w 1'
> >> wd_interval = 3
> >> other_pgpool_hostname0 = '10.100.2.71'
> >> other_pgpool_port0 = 9999
> >> other_wd_port0 = 9000
> >> 
> >> virtual IP starts up great and properly moves to the secondary pgpool server
> >> if you stop pgpool.  However, the ifconfig becomes defunct and never exits
> >> requiring a kill -9:
> >> 
> >> jeff at pgpool01:/tmp/pgpool$ ps -ef|grep pgpool
> >> postgres 19974     1  0 09:51 pts/0    00:00:00 /tmp/pgpool/bin/pgpool -n
> >> postgres 19975     1  0 09:51 pts/0    00:00:00 logger -t pgpool -p local0.info
> >> postgres 19978 19974  0 09:51 pts/0    00:00:00 pgpool: watchdog        
> >> postgres 19979 19974  0 09:51 pts/0    00:00:00 pgpool: lifecheck       
> >> jeff     20735  1615  0 09:54 pts/0    00:00:00 grep pgpool
> >> 
> >> jeff at pgpool01:/tmp/pgpool$ ps -ef|grep ifconfig
> >> root     20439 19979  0 09:52 pts/0    00:00:00 sudo ifconfig eth0:1
> >> 10.100.2.72 netmask 255.255.255.0 down
> >> root     20440 20439  0 09:52 pts/0    00:00:00 [ifconfig] <defunct>
> >> jeff     20737  1615  0 09:54 pts/0    00:00:00 grep ifconfig
> >> 
> >> System is Debian Squeeze.  Any idea how to fix this?  kill -9 of the sudo
> >> allows pgpool to exit.
> >> 
> >> -- 
> >> Jeff Frost <jeff at pgexperts.com>
> >> CTO, PostgreSQL Experts, Inc.
> >> Phone: 1-888-PG-EXPRT x506
> >> FAX: 415-762-5122
> >> http://www.pgexperts.com/ 
> >> 
> >> _______________________________________________
> >> pgpool-general mailing list
> >> pgpool-general at pgpool.net
> >> http://www.pgpool.net/mailman/listinfo/pgpool-general
> > 
> > 
> > -- 
> > Yugo Nagata <nagata at sraoss.co.jp>
> 
> ---
> Jeff Frost <jeff at pgexperts.com>
> CTO, PostgreSQL Experts, Inc.
> Phone: 1-888-PG-EXPRT x506
> FAX: 415-762-5122
> http://www.pgexperts.com/ 
> 
> 
> 
> 
> 
> 


-- 
Yugo Nagata <nagata at sraoss.co.jp>