Specifications for new Server and Disk Space Requirements

[robocp01]

We are looking at putting Cacti into production to probably graph 300-400 objects. We normally use Dell equipment, 2 - 4 core 2.66 GHz processors and probably 8 gig of Ram. How much disk space is utilized normally by the SQL database saying I want to keep a couple of years of historical data. Anyone have any ideas on an appropriate way to spec this out.

[BSOD2600]

1) general question, moving.
2) cacti uses MySQL for configuration of the devices, templates, scripts, etc. It's only a few MB in size.
3) RRDTOOL is used for storing/graphing the data. Figure a 'typical' cacti rrd file with 2 data sources (like Interface traffic) is ~185 KB. Soon as you increase the 'history' (aka rows, timespan, etc) then single rrd files can grow to a few MB each easily. Play around with rrdtool create commands with the length of data history/consolidation levels you're interested in. Then extrapolate the data out.

[DLNoah]

The short answer is, unless you're storing a whole bunch of data, not a lot of hard drive space. We have ~1000 hosts storing 7-12 data fields per host with the default 1 minute RRA setup, and the total size of our RRA folder is 545MB. Including the other plugins, weathermaps, etc that we're running, CentOS 5.4, and SQL, etc, we're using just over 5GB.

Just make sure you don't accidentally set the poller to e-mail the results to you (use the >/dev/null part of the cron line), and you won't have hard drive issues.

[gandalf]

... and make sure to truncate the cacti.log on a regular basis ...
R.

[johnnylately]

Very interesting. I have Cacti 0.8.7b on Windows 2003 with 1 minute polling, monitoring traffic on 619 ports and showing total 20GB. This does not include other graphs, which would bring total to 36GB. I have been considering moving Cacti to a Linux box. Would Cacti/rrdtool store data more efficiently on Linux?

[gandalf]

Very interesting. I have Cacti 0.8.7b on Windows 2003 with 1 minute polling, monitoring traffic on 619 ports and showing total 20GB. This does not include other graphs, which would bring total to 36GB. I have been considering moving Cacti to a Linux box. Would Cacti/rrdtool store data more efficiently on Linux?

Did you resize the rrd file? This seems to me quite huge for that few data.
In general, rrdtool will fetch as few sectors of an rrd file as possible. IMHO, the performance difference is not that huge apart from a quite new feature, introduced with rrdtool 1.2.26 or the like. It's named "fadvise" and avoids data prefetch from rrd files that is of no use but only fills up the cache of your server. This feature is known to work on current Linux systems. I suppose that this is not supported on Windows. Users reported an increase of rrdtool performance of up to 30% using this feature.
R.

[johnnylately]

Thanks for the reply gandalf. I am not sure what you mean by "resize the rrd file" so I will answer "no". I started with a clean install of Win2003 Server, used the Windows Cacti installer, set up for 1 minute polling, then started adding devices and interfaces. I have since added some plugins like Monitor and Weathermap. I have avoided manipulating the rrd files because I have not spent any time using the CLI.

And just to clarify, I mean I have 619 ports monitored, each rrd file is 33 MB. What would you say is a reasonable rrd file size? At what point should I take notice and start troubleshooting? BTW, my logs are clean, no errors, so I have not had reason (until now) to think that the file sizes are too large. Thanks.

[NLCoredump]

I have an similar solution running. Not for switches or network components.

We monitor about 400 hosts with about 10K datasources with 6500 rrd files.

Cacti including the databases now takes up to 22 GB This also include several dumps of daily static graphs for management and a lot of slack. The complete rra dir takes about 1.3GB.

All rra where created with standard cacti settings with 5 minute poll intervall.

Complete run to gather all data and process all files takes 17-20 second.

This setup includes al lot of non-standard datasource gathering as wel on the hosts as on the cacti server.

All runs on a hp dl380 in which holds 4 GB of mem and filled with disks to be able to created an striped mirror to have a compromise between data security and speed on writing to disk.

[gandalf]

Thanks for the reply gandalf. I am not sure what you mean by "resize the rrd file" so I will answer "no". I started with a clean install of Win2003 Server, used the Windows Cacti installer, set up for 1 minute polling, then started adding devices and interfaces. I have since added some plugins like Monitor and Weathermap. I have avoided manipulating the rrd files because I have not spent any time using the CLI.

And just to clarify, I mean I have 619 ports monitored, each rrd file is 33 MB. What would you say is a reasonable rrd file size? At what point should I take notice and start troubleshooting? BTW, my logs are clean, no errors, so I have not had reason (until now) to think that the file sizes are too large. Thanks.

You may want to refer to the rrdtool section of the documentation for a better understanding and for learning how to study an rrd file. 33MB for a single rrd file is really huge. It must either contain a lot of data sources (see again: rrdtool info) or a huge amount of data points (again: rrdtool info).
R.