cacti SLOOOOWW when circuit is down

[dkarlson]

We have Cacti installed and it's doing a fabulous job tracking a zillion measurements on a zillion devices across a Wide Area Network (about 25 sites)

However, we had a major circuit outage today (phone line cut at the street) and about a third of our sites could not be seen by Cacti.


During this time, the number of concurrent processes shot up on the hosting box... meanwhile *none* of the cacti graphs was getting updated.

I typically run
"php /var/www/cacti/cmd.php > /dev/null 2>&1"
as a cron job every 5 minutes...

I ran 'top' and could see a million (ok... not quite) cacti jobs stacked up.

When I run
php /var/www/cacti/cmd.php
from a command line, I see it tries each host/mib query combo for several seconds (on the nodes that are unavailable due to the outage) before moving on to the next host/mib combo.

So it appears that it never gets done with the cmd.php process within 5 minutes... and another one gets fired... and that one doesn't finish fast enough... but another one gets fired... etc.

Is this working as designed?

Is there a way to configure it so that either
1) only X cacti cmd.php processes will run at once?
What would that do to the graphs? (if there was only data collected every 10-15 minutes... instead of every 5)

or
2) to have cacti 'learn' that a given host/mib combo is unreachable and not try it again for X minutes/hours (but still try the other host/mib combos)

or
3) adjust the timeout to a lower value (what value would be safe?)

Any other ideas?

Thanks!

-Dave
Region 9 Education Service District
Oregon Public Schools
The Dalles Oregon

[TheWitness]

If you upgrade to cacti 0.8.6c, you will no longer have that SLOOOOOWWWWW down. We check for host availability in 0.8.6c and if the host is down, we don't continue to check interfaces and the like until it's back up again.

TheWitness

[dkarlson]

fabulous! Thanks for the Super Quick response!

I am running Fedora Core 1 with the most recent RPM of Cacti from

but that leaves me at
cacti-0.8.5a.fc1.i386.rpm
(based on http://www.cacti.net/downloads/packages/Fedora/1/)

Is there a more recent RPM build for FC 1? i.e. 8.6?

Or is this just another reason for me to bite off the in-place upgrade to FC3 that I've been putting off...?

Thanks again!

[TheWitness]

Check the web site. I think we have a cacti RPM. I'm not Mr. Unix by the by.

TheWitness