My two cents:
We have been backing up servers at night, but are now planning to open
up ADSM to many desktops.
To get an estimate of the impact:
* I installed ADSM on 10 desktops that I considered "power users" in the
Tech Support area.
(They were happy to be part of the test because they wanted their PC's
backed up automatically).
* I set up their DSM.OPT to keep their dsmsched.log files for 30 days.
* I let them run normally for a few weeks.
* I went back and collected copies of their dsmsched.log files and just
looked at them.
* The statistics told me that each incremental backup transferred a VERY
small amount of data each day.
We already have enough network capacity that we have our users install
software packages across the network; the amount of data transferred by
an incremental backup is generally much smaller than that, so we expect
minimal impact.
Our users use their PC's primarily for office applications; mail, word
processing, spreadsheets, graphics, terminal emulation, etc. PC's used
for heavy interactive analysis (i.e., PC's that are generating a lot of
data) might have a different backup profile.
I am counting on the fact that we have closed registration to limit the
number of "first backups" done at once.
>----------
>From: Vincent J. Anderson[SMTP:T442407 AT RUTADMIN.RUTGERS DOT EDU]
>Sent: Friday, February 21, 1997 2:15 PM
>To: ADSM-L AT VM.MARIST DOT EDU
>Subject: ADSM Network Impact
>
>I currently run a very small (10 clients) ADSM server. We are considering
>expanding service to several hundred and perhaps eventually several thousand
>additional clients. However, before we move forward, I've been asked to
>get an answer to the following question:
>
>"What impact will ADSM have on the network?"
>
>Unfortunately, "It depends" isn't going to work for me. :-(
>
>There is concern around here that opening up ADSM to many more clients
>is going to generate a large increase in network traffic that would, in
>turn, have an adverse effect on our network.
>
>Has this issue ever been a concern to your organization?
>
>What impact have you observed on your network? Have you been able to
>measure and quantify this, and if so, how?
>
>Have you ever attempted to predict the impact of additional clients? If
>so, how have you done it? How close to reality have you been able to
>get?
>
>Do you try to control the impact? If so, what do you do? Obviously,
>forcing compression on will reduce the amount of data that goes over
>the network. Is MAXSESSIONS an effective control? Have you tried to
>spread out the initial backups so that you don't have very many of them
>going on at once? What other controls are there?
>
>Have you ever had to make changes to the network due to the effect that
>ADSM traffic had on it? If so, what did you do?
>
>Finally, is there any particular documentation that I could/should look
>at to help me answer this?
>
>Thanks in advance for any help you can give me.
>
>Vince Anderson
>Rutgers University
>
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