What's this email? Why weren't my files backed up?
Files in your account are backed up regularly.
Unlike the monthly full backups, the nightly backups have limits on the files they can back up.
When the nightly backups have to skip files in your account because of those limits, System Backups sends you a mail like this:
/export/adams/1/z1234567/somelargefile.txt NOT backed up
max file size of 1048576 bytes exceeded
limit set by system default
You can usually just ignore this mail. It's just a notification, and you don't need to do anything.
Every file in your account is always backed up monthly - this is only for the nightly backups.
If you want to make sure that specific files (such as code for an assignment you're working on) always make it into the nightly backups, read on.
Otherwise, you can stop here.
There are two different limits applied to nightly backups:
- The largest individual file size that will be considered for the nightly backup.
- Set to 8MB by default.
- Can be changed.
- The maximum total combined size of all files that will go into the nightly backup.
- Fixed at 100MB.
- Cannot be changed.
You can override the filemax limit to include larger files in your backup if you want.
However, once the system has hit the treemax limit, it will not back up any more files that night.
To make sure your most important files get backed up before hitting the treemax, you can process other files last, or keep them out of the backup altogether.
Files and directories can be flagged as first or last in the backup queue, allowing you to give important files priority over unimportant ones.
Files and directories can also be excluded from the backups altogether to save space.
This is done by default for your web browser profile, your Trash folder, .o files, etc.
You can also include files to override wider exclusions.
Configuring your backups
All of these settings can be controlled by creating a hidden file called .backup in your home directory.
As an example:
# Not worried about large files, mostly care about hand-written code filemax 1M # ... except for PDFs which can get large filemax none *.pdf # Cat pictures can always be replaced. exclude *.jpg # Don't back up any temp folders exclude **/tmp/ # .. except for src/tmp include src/tmp/ # don't backup .dvi files except in directories called final exclude *.dvi include **/final/*.dvi # make sure that anything in my coursework directories gets considered first first COMP*/ # and give logfiles lowest priority last **/*.log
You can also put separate .backup files into individual subdirectories, and the settings there will apply to everything inside them (but not the level above).
For more exhaustive informtion, run man buff in a terminal.