Assistance with QoS config

hooneyrob · ‎10-29-2012

Hi All,

Wonder if one of you might be able to clear up a question. I'm looking at an existing config with the following detail in it:

class-map match-any Gold-Outbound

match ip dscp ef

!

policy-map ABC-GOLD

class Gold-Outbound

priority 5012

class class-default

fair-queue

It appears this is the only QoS reference in the entire config. Does this suggest that essentially:

1. They're matching anything not specific to Gold-Outbound.

2. Gold-Outbound is an EF queue.

3. A new map is created called ABC-GOLD which is getting a bandwidh of 512MB with a class default of fair-queue * I would have expected to see a parameter after fair-queue?

Any help appreciated. I have the full config...

Thanks, Rob.

smitesh kharecha · ‎10-29-2012

Hi Rob,

Please find answers to your Questions below:

1. They're matching anything not specific to Gold-Outbound.

- Anything which is not match explictly will be match by class-default. So answer is yes match is still there apart from Gold-Outbound, but it is implicit matching.

2. Gold-Outbound is an EF queue.

- Gold-Outbound is not an EF queue, it is just matching packets with dscp marking EF. It is priority Queue with bandwidth gaurantee of 5012.

3. A new map is created called ABC-GOLD which is getting a bandwidh of 512MB with a class default of fair-queue * I would have expected to see a parameter after fair-queue?

- Since anything which is not match explicitly, will be match by class-default. hence your ABC_GOLD class is getting whatever is defined under class-default.

Regards,

Smitesh

PS: Please rate helpful posts.

Joseph W. Doherty · ‎10-29-2012

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Posting

smitesh kharecha wrote:

It is priority Queue with bandwidth gaurantee of 5012.

Actually, on a router, it should be a LLQ which generally unlike PQ has an implicit policer.

smitesh kharecha · ‎10-29-2012

Point noted Joseph.

+5 for pointing subtle difference

Regards,

Smitesh

hooneyrob · ‎10-31-2012

Thanks for the replies, makes perfect sense.

The other config I'm looking at is attached - odd behaviour with this one, our VoIP system is not functioning correctly when connected via this site. Yet at other sites it works fine - it's not to with quality but actually not contacting the gateway so we wondered if anything was off in terms of config. There doesn't look to be.

Feel free to critique the config in general.

And thanks, I won\t be asking for further free resource. Much appreciated.

Config attached.

smitesh kharecha · ‎10-31-2012

Hi Robert,

If you are not able to connect to VoIP server totally, it might be that your router doesn't have routes for reaching VoIP server.

and if it is intermittent, then you ISP link might be bad; due to which you are getting intermittent connectivity to VoIP server.

PS: I'm assuming the site in question is a remote site and your VoIP server might be located in HQ or DC.

Regards,

Smitesh