MIBs variables for HUM graphs

[cmartinvalle]

Hi,

we need to graph the MIB variable 1.3.6.1.4.1.9.9.166.1.15.1.1.7 (cbQosCMPrePolicyBitRate) but expressed in % in HUM.

We know that it's not possible to make calculations in HUM, what I'd like to know is if there is any other MIB variable that measures exactly this % value.

I've been looking for it but I haven't found anything so any help would be wellcomed.

Regards.

[Joe Clarke · Accepted solution]

I don't know of any existing object that would do what you want, but it may be possible to use the EXPRESSION-MIB to create a custom MIB object that gives you the percentage. Here's a tech tip that details how to configure the EXPRESSION-MIB. It assumes the older, ciscoExperiment version which should be supported on most devices unless they are running really new code:

http://www.cisco.com/en/US/tech/tk648/tk362/technologies_configuration_example09186a008023267a.shtml

[cmartinvalle]

Hi,

finally we are going to implement these solution but first of all, we would like to know if changes in devices through EXPRESSION-MIB can damage the devices or are absolutly harmless because these changes will be made in very importants routers.

Does anyone know it?

Regards.

[Joe Clarke · Accepted solution]

I will not say that something is "harmless."  Bugs can always exist, and certainly this is not the place for a formal bug scrub.  However, I have seen no cases where configuring expressions has resulted in a crash.  We even have an EEM solution for auto-configuring the EXPRESSION-MIB, so we have been working that MIB out a bit internally with no ill effects.

But if you are worried (and a little paranoia is good), then I highly recommend you test your desired config out in a lab first to make sure what you want to do is safe for your environment.

[cmartinvalle]

OK, thank you very much for your answer. We will test it in our lab environment before apply it to the important routers.

About the EEM tool for auto-configuring the EXPRESSION-MIB, is it available for download? Could I use it?

Regards.

[Joe Clarke]

Yes, you can download the policy from http://forums.cisco.com/eforum/servlet/EEM?page=eem&fn=script&scriptId=1743 .

[cmartinvalle]

Last question: in case of breaking the device, what do we have to do to recover it? Do we have to load both IOS and startup-config?

Thank you very much and happy new year!

[Joe Clarke]

It depends on the problem introduced.  If you enable EXPRESSION-MIB persistence, and the very existence of the expression triggers a crash, then you will need to boot ignoring the config, then replace the current startup config with one which does not have the expression.  Otherwise, simply by reloading the device, the problem will clear itself.