Core question on Linux:
Can a sql client process connecting to a local mysql server change or set group file ownership on database files in /var/lib/mysql/<database-name> either by configuration, process properties, inheritance or commands?
Background:
After an upgrade to Piwigo photo gallery 2.5.2 running fine since mid-2013, the software was no longer functional showing database tables marked as crashed and not repairable.
Taking a closer look and running table repairs under mysql cmd interface gave "can't change ownership on .MYD files, Errcode 1.
Looking at the database files, there were several with .ftp group ownership. Changing the group ownership back to mysql and repairing the tables seemed to fix the problem initial but did not last.
The Piwigo database has 32 tables. There are two sets of tables, one with 7 and the other one with 25. When fixing all tables with mysqlcheck after changing all files to group mysql, either the 7 or the 25 are repairable. They alternate! If 7 are fixed, 25 are broken and when 25 are fixed, 7 are broken.
What I undertook so far is reflected on this piwigo forum thread:
http://piwigo.org/forum/viewtopic.php?pid=151096#p151096
There are also several mysql owned files with ftp group besides under Piwigo under /var/lib/mysql/mysql and /var/lib/mysql/performance_schema.
Any suggestion how to get this fixed is appreciated.
Versions:
mysql: Ver 14.14 Distrib 5.5.35, for debian-linux-gnu (x86_64) using readline 6.2
Linux: 3.10-3-amd64 #1 SMP Debian 3.10.11-1 (2013-09-10) x86_64 GNU/Linux
Thanks,
Dan