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sw-engine fails to start

StevieW

New Pleskian
Hi guys,

on a fresh installation of Ubuntu (at first 14.04 but on 12.04 the same problem occurs) I installed Plesk via the autoinstaller.
It seems to be all fine except I cannot open Plesk in the browser.

The web browser shows "502 Bad Gateway", a look into the error_log at "/var/log/plesk/sw-cp-server" shows the following error:
Code:
2014/08/11 09:37:22 [crit] 4988#0: *4 connect() to unix:/var/run/sw-engine.sock failed (2: No such file or directory) while connecting to upstream, client: xxx.xxx.xxx.xxx, server: , request: "GET / HTTP/1.1", upstream: "fastcgi://unix:/var/run/sw-engine.sock:", host: "xxx.xxx.xxx.xxx:8443"

So the problem seems to be the sw-engine service that cannot be started.
If I try to start it manually with `/etc/init.d/sw-engine start` it just fails:
Code:
 * Starting Plesk engine pool manager sw-engine-fpm           [fail]

I have no idea where to find any startup error log for sw-engine, where I could find any further information.
I hope you can help me! :)
 
With a friend I found the bug.

The following solves or (at least) bypasses the bug:

1.) Open /opt/psa/admin/conf/php.ini with a editor of your choice
2.) Comment out the last line so you get:
Code:
;zend_extension = "/usr/lib/x86_64-linux-gnu/php/modules/sw-engine/opcache.so"
(Mind the semicolon at the beginning)
3.) Save & close the file.
4.) Restart plesk
Code:
/etc/init.d/psa stopall && /etc/init.d/psa startall

I can't explain it, but at least it solved the problem for me.

And it seems that this is a common error on Virtual Servers by the german hosting provider 1und1.
 
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