Today my SuperDuper! backup failed, complaining about disc space. The log showed the error occuring with a file under /.MobileBackups. Say what?
This turns out to be a feature of Time Machine in OSX 1.7 – Backups are made locally in addition to your external drive. I don’t want this behaviour, so I disabled it:
Today I got tasked with removing duplicate mails from a mail folder with over 100,000 mails in it. Doing this from a mail client is so impractical, it’s not even worth giving any thought at all. Fortunately, the mailbox is on a mail server using Maildir style mailboxes, so I knew this could be done with minimum effort.
I discovered the ‘reformail’ utility, part of courier-imap, and after a few trial runs, I settled on the following:
# cd /path/to/mailbox/Maildir/cur
# for i in `find . -type f`; do reformail -D 10000000 /tmp/duplicates <$i && rm $i; done
-D looks for, and deletes duplicates.
10000000 is the length of the temporary file where a list of message IDs will be written
/tmp/duplicates is the aforementioned temporary file.
The temporary file needs to be big enough to accommodate the message ID of each mail. In this particular case, I have found the average length to be 54 characters, but I would suggest using around double that to be safe. So adjust to your needs.
In a big mail folder, and especially on ext3, this will take a long time to complete.
You may have come across this problem: say you have a MySQL database called ‘myblog’ which you’re moving to a new server on a different provider, and said provider doesn’t allow you to name the database, but instead use their own scheme, ‘user82_db1′ for example.
If you happen to have views in your database, this will cause the import to fail, as those views would still refer to ‘myblog’ instead of the new database.
Fortunately, this is easily fixed using the ‘rpl’ command. Say your database is backed up as ‘myblog-backup.sql’:
# rpl “\’myblog\’.” “\’user82_db1\’.” myblog-backup.sql
This will replace any instance to ‘myblog.’ with ‘user82_db1.’ and allow you to import a working database.
I get this kind of problem every day: “We’ve run out of disc space on our Plesk server – what’s taking up all the space?” The answer, almost every time, is “logs.” Plesk doesn’t enable log rotation by default, so logs can end up taking a lot of space.
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