Alta Video storage management

Last modified: Monday March 08, 2021.

High resolution video files of the types created by security cameras can require large amounts of storage in order to meet your corporate retention policies for these recordings. To ensure that your Alta video security systems does not run out of storage, the Alta Video software performs regular management of the video files stored on your Alta Cloud.

• Storage used by your cameras
• Storage management configuration options
• Drive cleanup
• Examples

Storage management is based around the concept of removing the videos that are the oldest from each camera (when recorded using the Retention period — Max option), or removing the videos from each camera after a defined number of days have passed.

Storage used by your cameras

Your Avigilon Ava cloud-native cameras record to their in-built storage system. Avigilon Ava cameras without in-built storage, or third-party cameras connected to Alta Cloud Connectors have their video footage saved to the hard disk array on the Alta Cloud Connector.

You can monitor the storage across all of the disks within your Alta Cloud Connectors. You can also monitor the storage being used by each camera.

Storage management configuration options

Alta Video storage management includes the following settings that you configure. These are:

• Best effort — Alta Video uses several methods to prevent your storage disks from becoming full.
• Fixed number or days — you configure the number of days for which video is to be stored. After this time, the recordings are deleted.
• Min or Max number of days — you configure the minimum or maximum storage parameters, and Alta Video uses these as the storage management parameters.
• Min retention period — used to specify a minimum time to keep the video (storage disk capacity allowing). For example, you can specify that you must keep video for at least 14 days, provided you have sufficient disk space available.
• Max retention period — mainly used to ensure compliance with data protection regulations, such as the European Union's General Data Protection Regulation (GDPR). Use this setting when you need to configure the maximum settings. For example, to comply with the compliance statement "we store videos for up to 28 days", set the Maximum retention period to 28 days.

  Any videos older than the Max retention period are automatically deleted.

  With the Max retention period set to Max, your Avigilon Alta video management system stores as much video as possible, only deleting the oldest content when the storage disks are approaching full.

Drive cleanup

Periodically, Alta Video runs a script to remove old video files. This script runs to a regular schedule, and is also called if the storage being used approaches the maximum available to the Avigilon Alta video management system. The system tries to remove the minimum amount of data necessary to keep the storage system available for new video.

When this script runs, it removes files in the following order:

1. All recordings with video that is older than the Max retention period is removed.

   This does not apply if the Maximum retention period is set to Max.

2. If the disks still do not have sufficient free space available, then all devices that have video that exceeds the Minimum retention period have the oldest data removed.  This process is repeated until either there is sufficient space available on the storage drives, or until all devices have no data older than the Minimum retention period.
3. Only if insufficient disk space has been recovered in the previous steps, further deletion of data takes place. This deletes video without regard to the configured settings, as the lack of available disk space is preventing the Avigilon Alta video management system from functioning correctly.

Examples

Use the following example to help visualize the processes to ensure yourAlta Cloud Connectors do not run out of disk space.

Key to the storage management graphs

Scenario 1 — No storage issues

In this scenario, your Avigilon Alta system has available disk space, perhaps because the system has only recently been set up.

Scenario 1 - Delete data that exceeds the maximum retention period

In this situation, each time the storage management scripts run, any data that exceeds the configured Maximum retention period is deleted, in line with your configured policy.

Scenario 2 — Disks starting to fill up

Here, the storage disks are starting to fill up, perhaps because more cameras have been added to the Alta video security systems. To manage this storage problem, in addition to the stage 1 removal process, any video from devices that are configured with a maximum retention period of Max start having the oldest data removed.

Scenario 2 - Start to delete oldest data where the maximum retention period equals Max

This ensures that all streams that are configured with a minimum retention period keep that minimum amount of storage, in line with your policies. The amount of data stored for each device varies.

As the disks fill up further, the system continues to remove any data not restricted by a minimum retention period limit.

Scenario 2a - Delete data using the minimum retention period as a limit

Eventually, if the amount of video being recorded exceeds the available storage and the minimum retention period settings, the situation where the disks approach the point where only data that has minimum retention periods are left, meaning that without further and more drastic action, the storage will become completely used, meaning that no further video can be stored.

Scenario 2b - Delete more of the oldest data using the minimum retention period as a limit

Scenario 3 — Very low amounts of storage

Now, the only way to free up sufficient storage to keep the Alta video security systems stable is to start ignoring the minimum retention period configurations and to start removing the oldest data, regardless of retention settings.

Scenario 3 - Delete the oldest data without regard to retention periods