How to monitor the QoS of an TCP/IP WAN.

[Rui Vilao]

Greetings,

My servers are connected to a private WAN interconnected via CISCO routers.

However sometimes we are loosing IP connections.
I have already done some measures via ping which indicate the ICMP response takes a bit more time.

Any hints on the commands I should enter on the HP boxes in order to troubleshoot/measure the QoS of the network.

TIA,

Kind Regards,

Rui.

[harry d brown jr]

Glance should do it for you.

Which hpux version? 10.20, 11.00, or 11.11?

live free or die
harry

[Rui Vilao]

Thanks for your suggestion Harry.

What kind of metris do you recommend?

Regards,

Rui.

[harry d brown jr]

Collision rate and error rate are two metrics I key on. You should have an almost zero error rate, and as close to zero for collisions as possible.

live free or die
harry

[Christopher Caldwell · Accepted solution]

Not exactly the answer to the question you asked, but if you believe there are WAN issues, I'd look at the Ciscos first. At best, the HPs will exhibit symptoms of WAN issues, but the HPs probably won't help you find the issues.

Trend the Cisco's interface metrics. Look at drops vs. total packets moved and packets per second. Check to make sure the input/output queues look reasonable.

If you're using frame-relay and your utilization seems reasonable for the sized circuit you have, check fecn and becn to see if your telco provider is dumping packets because of frame-relay network issues.

There's a package called mrtg at http://people.ee.ethz.ch/~oetiker/webtools/mrtg/mrtg.html you can use to plot these stats if you don't have NNM.

[Rui Vilao]

Christopher,

Thanks for your contribution!
I have already downloaded and installed MRTG and the required libs
from the HP porting center...

I am already retrieving the statistics
for In/Out.
Is there a way to get also collision
and error rates?

Kind Regards,

Rui.

[Steven Sim Kok Leong]

Hi,

You can interface mrtg.cfg with a shell or perl script that remsh or ssh to your server to sieve from netstat output the required statistic for graphical display.

Hope this helps. regards.

Steven Sim Kok Leong
Brainbench MVP for Unix Admin
http://www.brainbench.com

[Rui Vilao]

Steven,

Thanks for your mail.
But a was rather looking for a way to get this information from some routers (Cisco/Motorola)...

Regards,

Rui.

[Christopher Caldwell]

>Is there a way to get also collision
>and error rates?

By default, mrtg queries for bandwidth related MIBs. However, on the latest versions of mrtg, supposedly you can query and report any SNMP parameter.

Buyer beware, mrtg usually likes to plot one thing against another (example In vs. Out), so be creative ;-).

A listing of MIBs/OIDs is available from
ftp://ftp.cisco.com/pub/mibs/

Look at
ifInErrors
ifOutErrors
locIfCollisions

The router manual should have the MIBs/OIDs in the back.

With mrtg, you can refer to a parameter by name or number.

The MIB/OID documentation can be mind numbing. If you start to get a headache, use snmpwalk to query a router or host.