I was looking at the options and I can't see a way to mark a backend server as dead. For now I've just been stopping apache on the server to make pound see it as dead.
Another question: If a server is marked as "DISABLED" does pound still check it for availability? Meaning does pound still ping the HTTP port to see if it's alive, if the server has been set to DISABLED? The reason behind all these questions is: 1- I can't add/remove backend servers to pound without restarting pound and that would force all our customers to be completely logged out and have to log back in 2- I'm thinking about making a large list of possible backend servers, pre-populating my /etc/pound.cfg with them all, and then setting the ones that are off to DISABLED. 3- I'll update my nagios plugin that monitors the pound servers to detect DISABLED and just ignoring it. So only alarm on dead servers. That's my plan at least. On Tue, Jun 18, 2013 at 1:38 PM, D. R. <dav...@gmx.de> wrote: > Brad, > > for example look here: > http://linux.die.net/man/8/poundctl > *-B/-b n m r* Enable/disable a back-end. A disabled back-end will not be > passed requests to answer. Note however that existing sessions may still > cause requests to be sent their way. We do the same like Joe said: shut > your backend down. > > > David > > > Am 18.06.2013 19:32, schrieb Joe Gooch: > > Because you’re using session affinity, and you still have active > sessions attached to that host.**** > > ** ** > > A backend can be Alive or Dead. It can also be Enabled or Disabled.**** > > ** ** > > Enabled means it can receive new connections. (connections not in our > session database)**** > > Disabled means it cannot receive new connections.**** > > ** ** > > Alive means it can receive connections at all. (is it actually listening > to the port)**** > > Dead means it’s down. (when a host is marked down, its session database > is immediately cleared… forcing those connections to find another backend > on their next connection in)**** > > ** ** > > Poundctl manipulates Enabled/Disable, leading to a graceful/quiesce > shutdown type behavior. (otherwise, clients would lose their session when > a backend is disabled)**** > > ** ** > > If I want a non graceful shutdown, I’ll either shut down apache on the > backend, or use iptables on the LB or the backend to reject access to the > appropriate host+port.**** > > ** ** > > Joe**** > > ** ** > > *From:* Brad Allison [mailto:brad.alli...@gmail.com<brad.alli...@gmail.com>] > > *Sent:* Tuesday, June 18, 2013 1:22 PM > *To:* pound@apsis.ch > *Subject:* Re: [Pound Mailing List] poundctl command simply do not work*** > * > > ** ** > > Okay. Now using -1 for the listener I see the backend server is listed as > status="DISABLED". So that part worked.**** > > ** ** > > But I also see traffic is still being sent to that server and hostname > keys are still pointed to that server. I also see in the pound.log that > it's still sending request to that "DISABLED" server.**** > > ** ** > > So if it's DISABLED in pound why would pound still continue to send > traffic there?**** > > ** ** > > The data:**** > > [root@lalalqa-lb-01 ~]# /usr/sbin/poundctl -c /var/lib/pound/pound.cfg -X* > *** > > <pound>**** > > <listener index="0" protocol="HTTPS" address="0.0.0.0:443" > status="active">**** > > </listener>**** > > <service index="0">**** > > <backend index="0" address="10.0.2.21:443" avg="0.000" priority="5" > alive="yes" status="DISABLED" />**** > > <backend index="1" address="10.0.3.22:443" avg="0.000" priority="5" > alive="yes" status="active" />**** > > <session index="0" key="derm-auto.lalalqa.com" backend="1" />**** > > <session index="1" key="demo.lalalqa.com" backend="1" />**** > > <session index="2" key="testing.myqa.com" backend="0" />**** > > <session index="3" key="ophth.lalalqa.com" backend="0" />**** > > </service>**** > > </pound>**** > > ** ** > > From pound.log:**** > > ** ** > > Jun 18 17:15:38 lalalqa-pound-01 pound: testing.myqa.com 173.255.181.79 - > - [18/Jun/2013:17:15:38 +0000] "GET > /static/images/layout/footer-tail-bg.gif HTTP/1.1" 200 49 " > https://testing.myqa.com/ema/static/css/ema.css?build=3.0.0.7.8&rev=34505"; > "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:21.0) Gecko/20100101 > Firefox/21.0" (- -> 10.0.2.21:443) 0.026 sec**** > > Jun 18 17:15:38 lalalqa-pound-01 pound: testing.myqa.com 173.255.181.79 - > - [18/Jun/2013:17:15:38 +0000] "GET > /static/yui/2.9.0/build/assets/skins/sam/sprite.png HTTP/1.1" 200 3745 " > https://testing.myqa.com/ema/static/css/ema.css?build=3.0.0.7.8&rev=34505"; > "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:21.0) Gecko/20100101 > Firefox/21.0" (- -> 10.0.2.21:443) 0.028 sec**** > > ** ** > > ** ** > > ** ** > > On Tue, Jun 18, 2013 at 10:46 AM, Joe Gooch <mrwiz...@k12system.com> > wrote:**** > > Try using -1 as the listener.**** > > **** > > From your XML output it appears you use global services. (Services not > contained within the Listener block itself) **** > > **** > > Joe**** > > **** > > **** > > *From:* Brad Allison [mailto:brad.alli...@gmail.com] > *Sent:* Tuesday, June 18, 2013 9:37 AM > *To:* pound@apsis.ch > *Subject:* [Pound Mailing List] poundctl command simply do not work**** > > **** > > I'm trying to use the -b option for poundctl to disable a backend.**** > > **** > > The command runs with the three fields listener service and backend. The > command appears to work.**** > > **** > > But when I list out the -X option it says all backends are enabled... even > though I just disabled it. So the options for poundctl do not work.**** > > **** > > Notice how the status for the backend index=1 it still set to "active" > after I disabled it.**** > > **** > > [root@ ~]# /usr/sbin/poundctl -c /var/lib/pound/pound.cfg -b 0 0 1**** > > **** > > [root@ ~]# /usr/sbin/poundctl -c /var/lib/pound/pound.cfg -X**** > > <pound>**** > > <listener index="0" protocol="HTTPS" address="0.0.0.0:443" > status="active">**** > > </listener>**** > > <service index="0">**** > > <backend index="0" address="10.0.2.21:443" avg="0.000" priority="5" > alive="yes" status="active" />**** > > <backend index="1" address="10.0.3.22:443" avg="0.000" priority="5" > alive="yes" status="active" />**** > > <session index="0" key="demo.lalala.com" backend="1" />**** > > <session index="1" key="107.11.11.11" backend="1" />**** > > </service>**** > > </pound>**** > > **** > > ** ** > > >
