Posted by Anonymous on September 16, 2010 at 7:13am
I've pretty much followed the instructions on http://groups.drupal.org/node/80244 to setup mercury. But at my surprise , the whole setup assume everything will be on the same server. So i would like to ask :
- Is there a way to have all the applications having their own server and still have bcfg2 and hudson manage all that automatically without much intervention from the user and still use the mercury scripts ?
Thanks
Comments
re: Mercury and multiple application servers
Yes and no.
We do have options in /etc/mercury/server_tuneables to turn services off:
apache
hudson
memcached
mysql
tomcat (used for apache solr)
varnish
And these could used to create an apache-only (or mysql-only or apache-solr-only or varnish-only) server (all pieces will still be installed but disk space is cheap and this could be use for fail-over).
However, we don't have the pieces in place yet to point to the services to services on other servers - this would to be done by you (ie, modifying the apache solr drupal module config to not use localhost).
Hope this helps,
Greg
--
Greg Coit
Systems Administrator
http://www.chapterthree.com
Got it
Thanks for the explanation
Will Apache deliver on port 80 without Varnish?
I am considering switching Varnish off (and use Boost again!) using server_tuneables because of a serious problem I cannot find any solution for (see http://groups.drupal.org/node/97324#comment-331149).
I wonder if Apache will automatically start delivering over 80 if Varnish is switched off -- or do I need to do anything more than setting Varnish off in server_tuneables?
---
Tomáš J. Fülöpp
http://twitter.com/vacilandois
re: Will Apache deliver on port 80 without Varnish?
I'm sorry your having issue with Varnish - we've not seen this problem on our servers.
If you do decide to turn varnish off, then apache will need to be reset to port 80 in the /etc/apache2/ports.conf file.
Hope this helps,
Greg
--
Greg Coit
Systems Administrator
http://www.chapterthree.com
Thanks a lot for your answer,
Thanks a lot for your answer, Greg. I'll switch off Varnish and change Apache's port as you've indicated.
Btw, I am now pretty sure Varnish was causing the problem we have been experiencing here. Twice it already happened that there was absolutely no reply from the website (error message from the browser, not from Varnish). First time I was not at my desk, so I solved it quickly by a reboot, but today when it happened again I connected and checked that Apache was running, as was Varnish and Memcached.
The last lines in error.log were
[Mon Nov 08 12:07:26 2010] [notice] child pid 10397 exit signal Bus error (7)[Mon Nov 08 12:43:08 2010] [notice] child pid 10407 exit signal Bus error (7)
[Mon Nov 08 12:54:08 2010] [notice] child pid 10398 exit signal Bus error (7)
[Mon Nov 08 15:19:24 2010] [notice] child pid 10422 exit signal Segmentation fault (11)
[Mon Nov 08 16:02:28 2010] [notice] caught SIGTERM, shutting down
I only had to restart Varnish and the site was running again. Ideas as to why, or what should be the next steps in debugging this?
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Tomáš J. Fülöpp
http://twitter.com/vacilandois
Solved by memory use optimization
My issue is gone now, though it may not be solved.
I optimized some memory-hungry functions and especially several large forgotten values in table 'variable' (used the excellent http://drupal.org/project/variable_clean) that required high PHP memory limits and consequently caused "server reached MaxClients".
Now that the server never goes into swap, the "child pid ... exit signal" is not appearing anymore.
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Tomáš J. Fülöpp
http://twitter.com/vacilandois
I can confirm Varnish
I can confirm Varnish crashing issues on my setup as well. In some cases I've had to manually force start..
I haven't had time to review logs (im still in dev stage of the site it's running) but when I near production I'll contribute my findings.
Ben