THE INFORMATION IN THIS ARTICLE APPLIES TO:
- WAFS/CDP, version 3.7.1 and earlier
For WAFS version 4.0 and later, refer to
KB article #11016.
DISCUSSION
Your
antivirus configuration can affect file-access performance when using the
system. This article describes how to optimize your antivirus setup for use
with WAFS/CDP.
Choose from the following antivirus configurations based on your
particular needs:
Antivirus at each end-user's workstation - If each of your
end-users' workstations are protected, the possibility of an infected file
is eliminated and there is no need to run antivirus on the computer running
an Agent. This is the most effective level.
Protection at the server running the Agent - Instead of managing
antivirus software on each user's workstation, some IT managers prefer to
run antivirus software on the servers that run the Agent. When not done
properly, this can affect the performance of user file access. Refer to "To
configure antivirus software at the computer running an Agent" below for
important exclusion setup notes.
Protection at Server - All files move through the Server. You can,
therefore, run antivirus software on the Server and scan the Server's root
before propagating files to the Agents.
Running antivirus software on an Agent can degrade the performance if not
properly configured. The performance hit is caused by the antivirus software
thinking that multiple copies of a file are opening. It may scan the same
file up to 3 times when a user opens the file once. It may also perform
background scans that appear as regular CPU cycles (Norton, E-Trust,
NOD32, etc), as well as process scans of the application. If the file is in
a linked folder, then the antivirus software scans the file from the
original location upon open, AND from inside the replicate drive (e.g.,
F:\_MySrv\MyVol). Finally, the file is seen
internal to the engine (e.g., C:\WINDOWS\AVMF
or D:\AVMF), and scanned again.
In addition to on-the-fly scan when a file is changed, some antivirus
software includes a daily scan. In this case, if it is necessary to do this
daily scan, it might be useful to do it when the Agent is offline. For
example, you can schedule the Agent so that it is online 22 hours a day, and
offline for two hours during times when users are less likely to use the
Agent. During that time, the computer running the Agent can do backups,
virus scans, and so on.
To configure antivirus software at the computer running an Agent
Virus checkers allow directories to be excluded from the antivirus scan
(often called "exclusions"). The following exclusions should be made at each
Agent:
- Always exclude directories AVM0 and AVMF.
All data mirrored on the C drive will be in C:\Windows\AVMF
and all data on any other drive will be in <drive_Letter>:\AVMF
(e.g., D:\AVMF).
- Exclude the entire new drive letters (e.g., F:\_MyServer
).
- If your antivirus scans processes (especially E
Trust, Innoculan, Symantec Tamper Protection, Trend
Micro OfficeScan/Server protect), always exclude
AvlAgt.exe.
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Some local server antivirus applications in corporate environments,
like McAfee, are controlled by a central monitor
service run by your IT at headquarters. Exclusions must be specified
at that central console; the console then pushes them out. The
exclude list you see at each remote site is ignored in these
hierarchical topologies.
If slowness persists for user access to CAD files, exclude the CAD
file extension from the workstation antivirus, and check the
performance again.
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