monitor disk space

[office politics]

System Administration Toolkit: Monitoring disk space and usage

Automatic monitoring

Monitoring disk space usage by hand is fine, but you don't want to be constantly running df (or even du) to determine the disk space being used, or that is available. You can automate the process and automatically send the administrator (or an administration group) an e-mail when the available space gets below a certain level. The script in Listing 10 monitors disk space, and you can set the warning (warninglimit) and emergency (lowlimit) limits, as well as the list of file systems that are checked.

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they provide a script to monitor disk space and send an email when a certain amount of low disk space is identified.