Update tasks and how they work

Use the update task to get the most current DAT files, scanning engine, and Service Packs and Patches.

VirusScan Enterprise includes a default update task. The default task is scheduled to update every day at 5:00 p.m. with one-hour randomization. You can also create additional update tasks to meet your updating requirements.

This diagram shows how a typical update task works:

Update task activities

These activities occur when you run an update task:

A connection is made to the first enabled repository (update site) in the repository list. If this repository is not available, the next site is contacted, and so on until a connection is made, or until the end of the list is reached.
An encrypted CATALOG.Z file downloads from the repository. The file contains the fundamental data required to update. This data is used to determine which files and/or updates are available.
The software versions in the file are checked against the versions on the computer. If new software updates are available, they are downloaded.
Once the update is checked in to the repository, the update is verified to confirm that it is applicable to VirusScan Enterprise and that the version is newer than the current version. Once this is verified, VirusScan Enterprise downloads the update when the next update task runs.

Update task interruption

If the update task is interrupted for any reason during the update:

A task updating from an HTTP, UNC, or local site resumes where it left off the next time the update task starts.
A task updating from an FTP site does not resume if interrupted during a single file download. However, if the task is downloading several files and is interrupted, the task resumes before the file that was being downloaded at the time of the interruption.

Update using EXTRA.DAT

An EXTRA.DAT file can be used as a temporary measure in an emergency. The EXTRA.DAT is downloaded from the repository on each update. This ensures that if you modify and re-check in the EXTRA.DAT in as a package, all VirusScan Enterprise clients download and use the same updated EXTRA.DAT package. For example, you may use the EXTRA.DAT as an improved detector for the same potentially unwanted program or additional detection for other new potentially unwanted programs. VirusScan Enterprise supports using only one EXTRA.DAT file.

Tip: When you have finished using the EXTRA.DAT file, you should remove it from the master repository and run a replication task to ensure it is removed from all distributed repository sites. This stops VirusScan Enterprise clients from attempting to download the EXTRA.DAT file during an update. By default, detection for the new potentially unwanted program in the EXTRA.DAT is ignored once the new detection definition is added to the daily DAT files.