Daily rotation not working

[GnaXi]

Hi,

I've set the "CONFIG_rotation_daily" to "1", but backups older than 24 hours are not being deleted.
I installed this on a server with very little space left, so when this feature wasn't working, the hard drive was full within 3 days.

[BigAndini]

Can you please give some more information? For me it's working. So it's the backups of the last 3 days, not the last 3 backups. When I do some backups from today it can happen that the system keeps more than 3 backups.

Interesting information would be an ls -l from the folder of the database in the daily directory to check the timestamps.

Within the script it's a simple find /path/to/daily/db/backups -mtime +1 -type f -exec rm {} \;. So no special magic here.

[GnaXi]

-r-------- 1 root root 2146709504 Aug 10 01:03 daily_otrs_2020-08-10_01h00m_Monday.sql.gz
-r-------- 1 root root 19329774030 Aug 11 02:06 daily_otrs_2020-08-11_01h00m_Tuesday.sql.gz

Shouldn't the one from Monday have been deleted, when the Tuesday backup was created?

[BigAndini]

So the rotation mechanism only deletes files when the mysqldump command beforehand was successful. Your dumps are quite different in size, maybe there was a failure in execution. I did a small test:

[10:54:48 andi@wave ~/delete-test]$ touch -t 202008090000 file3
[10:54:59 andi@wave ~/delete-test]$ touch -t 202008080000 file3
[10:55:02 andi@wave ~/delete-test]$ touch -t 202008090000 file3
[10:55:06 andi@wave ~/delete-test]$ touch -t 202008080000 file4
[10:55:08 andi@wave ~/delete-test]$ ls -ltr
total 0
-rw-rw-r-- 1 andi andi 0 Aug  8 00:00 file4
-rw-rw-r-- 1 andi andi 0 Aug  9 00:00 file3
-rw-rw-r-- 1 andi andi 0 Aug 10 00:00 file2
-rw-rw-r-- 1 andi andi 0 Aug 11 10:53 file1
[10:55:09 andi@wave ~/delete-test]$ find -mtime +1
./file4
./file3
[10:55:16 andi@wave ~/delete-test]$

In automysqldump the find command uses only -mtime without the -daystart parameter. So find should calculate 24h backwards. I don't know when exactly your command was executed, but it looks like it should have deleted the first file due to it was last modified at 01:03 and the second one at 02:06. So the find command to clean it up is executed after the mysqldump.

I did it in one of my setups: worked pretty fine.

[GnaXi]

You were absolutely right. It ran out of space before it was able to finish!
I'm playing around with a smaller database backup now, to make sure that it doesn't run out of space before it gets to finish the backup.
However, it still seems to be saving 3 days worth of daily backups:
-r-------- 1 root root 214230953 Aug 18 01:01 daily_otrs_2020-08-18_01h00m_Tuesday.sql.gz
-r-------- 1 root root 215314989 Aug 19 01:01 daily_otrs_2020-08-19_01h00m_Wednesday.sql.gz
-r-------- 1 root root 214583477 Aug 20 01:01 daily_otrs_2020-08-20_01h00m_Thursday.sql.gz

I can confirm that it is actually deleting backups older than these, as I've had it running for about a week now.

[ahindrichs]

We have the same behaviour, with the setting "CONFIG_rotation_daily=1", which keeps three backup files.
Due to the size of the backup, we only want to save the last backup.

A solution can be to change mtime to mmin, like:

before:

AutoMySQLBackup/automysqlbackup

Lines 997 to 999 in 35dfe71

	find "${CONFIG_backup_dir}/${subfolder}${subsubfolder}" -mtime +"${rotation}" -type f -exec echo "dry-running: rm" {} \;
	else
	find "${CONFIG_backup_dir}/${subfolder}${subsubfolder}" -mtime +"${rotation}" -type f -exec rm {} \;

to:

find "${CONFIG_backup_dir}/${subfolder}${subsubfolder}" -mmin +"$((60*24*$rotation-60))" -type f -exec echo "dry-running: rm" {} \;
else
find "${CONFIG_backup_dir}/${subfolder}${subsubfolder}" -mmin +"$((60*24*$rotation-60))" -type f -exec rm {} \;

The behaviour should be compatible as far as it goes. If you want, I could create a pull request.