Monitoring local volumes for presence and capacity

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A volume becoming too-full or going missing can lead to data loss and downtime. Watchman Monitoring allows you to mark key volumes for monitoring using the PreferencePane.

This article shows you how to select which volumes should not go missing, and how full certain volumes are allowed to grow before you are notified.

Volumes listed include those connected via

  • FireWire
  • USB
  • ThunderBolt
  • iSCSI
  • Xsan
  • Mounted DMGs are also included

Network volumes are not available for monitoring at this time.


Use the PreferencePane to configure notifications when a volume is missing, or too full.

Use the PreferencePane to configure notifications when a volume is missing, or too full.

Get notified when a volume is missing.

Select a Volume from the list.

To receive notices if a volume goes offline, choose Monitor Presence

Adjust the time allowed before a notification is sent, from 1 to 59 minutes.

Get notified if a volume is too full

Select a Volume from the list

To receive noticies that the volume is too full, choose Monitor Capacity

Adjust the threshold at which a notification is sent from 1 to 99 percent. 

Considerations when setting thresholds

Regarding drives going offline, allowing for 0 minute (immediate) notification resulted in false positives.

Unlike other notices, Watchman Monitoring does not check this only on the agent's hourly run. We ship a background process called diskjournald to track which volumes are mounted, and when.

Monitoring Time Machine destinations for capacity is not recommended, as they can continue to serve their purpose even when 95% full. If backups can not complete in a given time frame, the Time Machine plugin will alert if backups cannot complete.


Automatically mounting volumes at the LoginWindow

Automatically mounting volumes at the LoginWindow

It is not necessary for a user to be logged in for Watchman Monitoring to run its daily inspections

When a locally connected volume is monitored for Presence, but there is no logged in user, notifications may be sent that the volume cannot be found.

Prevent this by selecting the checkbox "Prevent Missing Volumes warning by mounting volumes at the Login Window".

This checkbox does not effect Watchman Monitoring's software, rather, it sets a preference in OS X itself. This checkbox is the equivalent of running the the following command:

sudo defaults write /Library/Preferences/SystemConfiguration/autodiskmount AutomountDisksWithoutUserLogin -boolean true

Unchecking the box would be the same as running:

sudo defaults write /Library/Preferences/SystemConfiguration/autodiskmount AutomountDisksWithoutUserLogin -boolean false

On computers running Mac OS X Server, or, this checkbox will show as checked by default, as this reflects the state of the computer's configuration.

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