diff options
Diffstat (limited to 'FAQ')
| -rw-r--r-- | FAQ | 46 |
1 files changed, 45 insertions, 1 deletions
@@ -1,4 +1,4 @@ -Frequently Asked Questions about rancid - last updated 20040107. +Frequently Asked Questions about rancid - last updated 20050813. This FAQ contains information that may not apply directly to versions of rancid prior to 2.3. It also contains paths containing tags such as @@ -235,6 +235,50 @@ A. Certainly, but rancid does not provide such a mechanism natively. Two Obviously, the first option is the cleanest and most featureful, which is why the script mention in the second option is not provided. +Q. For approximately X hosts (configs) what size server should we be + considering - speed and data storage? +A. On modern machines it is unlikely you will have issues with disk space or + memory - A heavily laden access router with a complex config won't consume + more than a few megabytes of disk space for its configs over several + years time (roughly 3 times the sum of all the config or */configs/* over + 2 years is a decent approximation). + + Rancid is typically CPU bound if you have adequate network bandwidth. + Experience shows rancid takes around 50 Mhz * minutes / device of processing + power. This means that a 1Ghz machine can poll: + + 1000 Mhz * 60 (min/hour) / 50(Mhz min / device) = 1200 devices/hour + + That's obviously a ball park estimate which varies with many different + factors such as the CPU type and the types of devices on your network. + + +Q. How can I run rancid to make the most efficient use of resources (i.e. + run in the shortest amount of time)? + +A. You can adjust PAR_COUNT in rancid.conf to achieve maximum efficiency + during polling. You can watch the output of the standard unix command + vmstat command during polling to determine whether or not the cpu is being + wholly utilized - there should be little idle time and no process blocking. + + Another simpler method is to look at the time stamps on the rancid log + files, and adjust PAR_COUNT until the least amount of time is taken + during polling. Make sure all devices are being polled by rancid before + using this method - failing devices can extend the amount of time rancid + takes to finish by a *LONG* period and throw your times way off. + + It may help to run rancid niced (man nice) if it will be sharing + resources with other processes, as it may eat whatever is available if + PAR_COUNT is set high. This is done by changing the crontab to be + something like: + + 5 * * * * nice -19 /usr/local/rancid/bin/rancid-run + + If you _do_ share resources with other processes but want rancid to + run efficiently, probably the vmstat method above will work better - + rancid may take a little longer to run but you won't be stepping on + other people's toes. + Q. I'm still stuck on this problem. Where can I get more help? A. A discussion list is available, rancid-discuss@shrubbery.net. You must be a subscriber to post. Subscribe like this: |