Kernel killing varnish process due to out-of-memory issue
We're having an issue on our Mercury installation where Varnish will unexpectedly and require a manual restart -- this is obviously a pretty big deal given that our site effectively goes down until it is remedied. A look at the syslog reveals the following:
Feb 14 02:17:06 ip-xx-xx-xx-xx kernel: Out of Memory: Kill process 4493 (vshd) score 356911 and children.
Feb 14 02:17:06 ip-xx-xx-xx-xx kernel: Out of memory: Killed process 4493 nishd).Uninstalling Varnish
Varnish keeps on crashing on me, and since I have authcache and only one server, I'd rather not deal with it.
I removed it by apt-get remove varnish, and setting apache to port 80. Are there any other steps that I need to take to set the server to be like no varnish? What about the memory allocated to varnish in the bootscript, is that someone I'll need to clawback?
Thanks.
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serving from cache even if the backend is down
If apache or mysql goes down, or you accidentally upload bad code to your drupal site, or you put your site into maintenance mode, apache gives varnish a 5xx. Varnish knows better than to cache this page, but it will serve it if the object grace has expired. Fortunately, varnish has the ability to reset the grace and serve the "good" page from cache until apache returns a non-5xx on that page.
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