Virus update times

[Julian Field]

At 08:49 01/03/2004, you wrote:
>At 20:52 29/02/2004, you wrote:
>>Kevin Spicer wrote:
>>
>>>Theres been some discussion on the clamav list recently about the
>>>frequency of clients pulling database updates from their servers.  the
>>>most notable point was that several of the clam developers urged users
>>>to schedule their cron jobs at a random minute past the hour to try and
>>>get a better distribution of load on the servers.  I guess similar
>>>problems also afflict users of commercial scanners.
>>>
>>>Several things stuck me.
>>>1) Many (most?) MailScanner users use cron.hourly to schedule updates,
>>>therefore we, as a community, are probably responsible for a
>>>substantially increased load at one point every hour.
>>>2) Everyone updating at the same time increases the possibility of
>>>individual updates failing due to bandwidth/ server issues
>>>3) Any problems with the virus database introduced immediately before
>>>the point we all update are likely to affect all of us before they get
>>>fixed
>>>4) We all have the same window of opportunity in our update cycles
>>>during which a new virus could propagate very quickly, at least if we
>>>all updated at different times we may stand a better chance of slowing
>>>the rate of spread.
>>>
>>>I therefore propose that update_virus_scanners be moved from
>>>/etc/cron.hourly to a file in /etc/cron.d and that the minute at which
>>>it is scheduled in that file be generated either at random or be the
>>>same as the minute at which the file was installed.  Obviously this
>>>would involve generating the file as part of the install process.
>>
>>could it be possible to set this in update_virus_scanners with a random
>>value
>>i hope that this would not stop other scripts in cron.hourly.
>>
>>
>># vi /usr/sbin/update_virus_scanners
>>
>>#!/bin/bash
>>
>>sleep 300
>>
>>SCANNERSCONF=/etc/MailScanner/virus.scanners.conf
>>[...]
>>
>>
>>
>>or
>># crontab -e -umailscanner-user
>
>This is the new cron job. Delays by up to 30 minutes if you change the "0"
>to "1800". I will leave the delay at 0 by default for now, to see if this
>causes any problems or complaints. I might change the default to 1800 in a
>future release.

2nd thoughts. I am going to make the random delay 10 minutes for now as I
still want people to basically get updates every hour.


>#!/bin/bash
>
># Insert a random delay up to this value, to spread virus updates round
># the clock. 1800 seconds = 30 minutes.
># Set this to 0 to disable it.
>DELAY=0
>
>[ -x /usr/sbin/update_virus_scanners ] || exit 0
>if [ "x$DELAY" = "x0" ]; then
>   :
>else
>   logger -p mail.info -t update.virus.scanners Delaying cron job up to
>$DELAY seconds
>   perl -e "sleep int(rand($DELAY));"
>fi
>exec /usr/sbin/update_virus_scanners
>exit 0
>
>--
>Julian Field
>www.MailScanner.info
>MailScanner thanks transtec Computers for their support
>
>PGP footprint: EE81 D763 3DB0 0BFD E1DC 7222 11F6 5947 1415 B654

--
Julian Field
www.MailScanner.info
MailScanner thanks transtec Computers for their support

PGP footprint: EE81 D763 3DB0 0BFD E1DC 7222 11F6 5947 1415 B654