[mrtg] Hardware requirement for MRTG

[Huh, Jin (FXKIS.KOR)]

Dear fellow admins,

Now we are trying to implement MRTG server and monitor around 100 machines of network traffic usage and CPU performance. (Servers and Network devices)

Please let me know appropreate hardware requirement for MRTG server.
Thanks.
Sincerely,
Huh, Jin
Network Administrator
Fuji Xerox Korea Information Systems
ISC (Information System Centre)
Tel: [phone]
***@kor.fujixerox.com<mailto:***@kor.fujixerox.com>
This e-mail may contain confidential and privileged material for the sole use of the intended recipient. Any review, use, distribution or disclosure by others is strictly prohibited. If you are not the intended recipient (or authorized to receive for the recipient), please contact the sender by reply e-mail and delete all copies of this message.

[Steve Shipway]

This is discussed in more detail in the MRTG book here http://www.steveshipway.org/book (sorry for the advertising)

Basically, it depends on how many Targets you have, and whether or not you use external plugins or just SNMP checks.
So, if your 100 machines are being checks for 1 network card and 1 cpu stat, that would be 200 Targets, probably using SNMP only.

The main bottleneck for you will be Disk IO. You should get the fastest disks you can get as slow disk IO slows down polling and means more threads are running, increasing memory requirements.

A 200-Target installation is relatively small. We run about 14,000 Targets on our dual-Xeon 3GHz linux server with 4GB RAM, with still some spare capacity. You could certainly manage with a much smaller server. If running under windows you have a slightly higher requirement but not much.

Note that, for performance, you should use MRTG with RRDtool and a frontend such as Routers2, 14all or mrtg-rrd. While you can run in native mode, performance is far worse and you will find that you need a much larger server to cope with the load, as in Native mode MRTG will recreate all the graph images every 5 minutes, rather than only on demand. A native-mode MRTG may need 10 times as many resources as an RRD-mode installation.

Hope this helps,

Steve

________________________________
From: mrtg-***@lists.oetiker.ch [mailto:mrtg-***@lists.oetiker.ch] On Behalf Of Huh, Jin (FXKIS.KOR)

Now we are trying to implement MRTG server and monitor around 100 machines of network traffic usage and CPU performance. (Servers and Network devices)

Please let me know appropreate hardware requirement for MRTG server.

[Huh, Jin (FXKIS.KOR)]

Thanks Steve,

You've been a great help. I appreciate it.

Sincerely,
Huh, Jin
Network Administrator
Fuji Xerox Korea Information Systems
ISC (Information System Centre)
Tel: [phone]
***@kor.fujixerox.com<mailto:***@kor.fujixerox.com>
This e-mail may contain confidential and privileged material for the sole use of the intended recipient. Any review, use, distribution or disclosure by others is strictly prohibited. If you are not the intended recipient (or authorized to receive for the recipient), please contact the sender by reply e-mail and delete all copies of this message.


________________________________
From: Steve Shipway [mailto:***@auckland.ac.nz]
Sent: Wednesday, October 08, 2008 10:18 AM
To: Huh, Jin (FXKIS.KOR)
Cc: '***@lists.oetiker.ch'
Subject: RE: Hardware requirement for MRTG

This is discussed in more detail in the MRTG book here http://www.steveshipway.org/book (sorry for the advertising)

Basically, it depends on how many Targets you have, and whether or not you use external plugins or just SNMP checks.
So, if your 100 machines are being checks for 1 network card and 1 cpu stat, that would be 200 Targets, probably using SNMP only.

The main bottleneck for you will be Disk IO. You should get the fastest disks you can get as slow disk IO slows down polling and means more threads are running, increasing memory requirements.

A 200-Target installation is relatively small. We run about 14,000 Targets on our dual-Xeon 3GHz linux server with 4GB RAM, with still some spare capacity. You could certainly manage with a much smaller server. If running under windows you have a slightly higher requirement but not much.

Note that, for performance, you should use MRTG with RRDtool and a frontend such as Routers2, 14all or mrtg-rrd. While you can run in native mode, performance is far worse and you will find that you need a much larger server to cope with the load, as in Native mode MRTG will recreate all the graph images every 5 minutes, rather than only on demand. A native-mode MRTG may need 10 times as many resources as an RRD-mode installation.

Hope this helps,

Steve

________________________________
From: mrtg-***@lists.oetiker.ch [mailto:mrtg-***@lists.oetiker.ch] On Behalf Of Huh, Jin (FXKIS.KOR)

Now we are trying to implement MRTG server and monitor around 100 machines of network traffic usage and CPU performance. (Servers and Network devices)

Please let me know appropreate hardware requirement for MRTG server.

[Niall O'Reilly]

On Wed, 08 Oct 2008 01:50:44 +0100, Huh, Jin (FXKIS.KOR)

Post by Huh, Jin (FXKIS.KOR)
Please let me know appropreate hardware requirement for MRTG server.

It depends on how you set things up. Whatever you use as a
"standard utility server" will likely do the job.

Here below is a snapshot of one of our servers.
We could probably reduce the CPU load and the disk requirement
for MRTG by using RRD mode instead of traditional rateup mode.

joe(user)25: cat /etc/redhat-release
Red Hat Enterprise Linux ES release 3 (Taroon Update 4)
joe(user)26: fgrep -i mips /proc/cpuinfo
bogomips : 6383.20
bogomips : 6396.31
joe(user)27: top -b -n1 | head


11:03:14 up 316 days, 23:08, 1 user, load average: 4.35, 3.65, 2.85
290 processes: 289 sleeping, 1 running, 0 zombie, 0 stopped
CPU states: cpu user nice system irq softirq iowait idle
total 0.4% 0.0% 0.4% 0.0% 0.0% 4.8% 94.1%
cpu00 0.9% 0.0% 0.9% 0.0% 0.0% 0.0% 98.0%
cpu01 0.0% 0.0% 0.0% 0.0% 0.0% 9.7% 90.2%
Mem: 2055464k av, 2033060k used, 22404k free, 0k shrd, 156492k
buff
1419732k actv, 270440k in_d, 31244k in_c
joe(user)28: service mrtg status | fgrep running | wc -l
45
joe(user)29: grep '^Target' /usr/local/etc/mrtg/mrtg-*.conf | wc -l
4845
joe(user)30: du -sh /var/local/mrtg
1.3G /var/local/mrtg
joe(user)31:

As you can see, that box has 45 instances of MRTG, covering
4845 targets. These include performance figures both from
network equipment (bit/sec, pkt/sec, etc) and from the local
server (CPU, disk, DNS query rate, NTP time sync, etc).

Best regards,

Niall O'Reilly
University College Dublin IT Services