Plugin Updates

The following table describes the behavior of differential plugin updates for agents linked to either Tenable Vulnerability Management or Tenable Nessus Manager.

Note: Tenable Nessus Agent checks its linked manager for plugin updates every 24 hours.

Linked Manager	Differential Update	Full Update
Tenable Vulnerability Management	The agent performs a differential update when any of the agent plugin sets are 15 days or less behind the Tenable Vulnerability Management plugin sets.	The agent performs a full plugin update at scan time for any required plugin set if the agent does not have any plugins for that plugin set. For this reason, when you perform an agent vulnerability or inventory collection scan for the first time, expect the scan to use more bandwidth than the subsequent vulnerability or inventory scans. The agent also performs a full plugin update when any of the agent plugin sets are more than 15 days behind the Tenable Vulnerability Management plugin sets. The agent deletes unused plugin sets after a configurable amount of time (for more information, see the days_to_keep_unused_plugins advanced setting). After the amount of time passes, the agent deletes the unused plugin sets.
Tenable Nessus Manager	The agent performs a differential plugin update when the agent plugin set is 5 days or less behind the Tenable Nessus Manager plugin set.	The agent performs a full plugin update when the agent plugin set is more than 5 days behind the Tenable Nessus Manager plugin set.

Linked Manager

Differential Update

Full Update

Tenable Vulnerability Management

The agent performs a differential update when any of the agent plugin sets are 15 days or less behind the Tenable Vulnerability Management plugin sets.

The agent performs a full plugin update at scan time for any required plugin set if the agent does not have any plugins for that plugin set. For this reason, when you perform an agent vulnerability or inventory collection scan for the first time, expect the scan to use more bandwidth than the subsequent vulnerability or inventory scans.

The agent also performs a full plugin update when any of the agent plugin sets are more than 15 days behind the Tenable Vulnerability Management plugin sets.

The agent deletes unused plugin sets after a configurable amount of time (for more information, see the days_to_keep_unused_plugins advanced setting). After the amount of time passes, the agent deletes the unused plugin sets.

Tenable Nessus Manager

The agent performs a differential plugin update when the agent plugin set is 5 days or less behind the Tenable Nessus Manager plugin set.

The agent performs a full plugin update when the agent plugin set is more than 5 days behind the Tenable Nessus Manager plugin set.