Make logrotate mandatory

[JKawohl]

No description provided.

[xoxys]

@JKawohl @enbrnz I need some more background information on the build-in log rotate logic. How does it work in detail? There is only one flag, the size, but what happens in detail if the size is reached? Just create a new file? No compression? No max file limit? Something else?

[JKawohl]

Need to test this:

[JKawohl]

from the docs:

• A new logfile is created with a new name when the old logfile reaches the defined limit.
• If a rotated log file is already present, it will be overwritten.
• If enabled, only the active log file and one rotated file are stored.

[enbrnz]

I think we should enhance this role to install logrotated configuration for the owncloud.log file.