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New Member

QoS Turst for Cisco 4948E switch

I am trying to trust the marking for voice traffic in a Cisco 4948E interface/port and it looks like the "qos" command is not working as described in the  command reference.

Is there any particular way to configure a port to trust the QoS marking received in a Cisco 4948E - 10GIG switch?

1 ACCEPTED SOLUTION

Accepted Solutions
Hall of Fame Super Bronze

QoS Turst for Cisco 4948E switch

I'm not sure what you find unclear. The QoS behavior has changed and the URL I posted indicates the hardware affected by this change. The 4900 switch is not the same platform/hardware as the 4948E switch.

You need to follow the documentation on the platform in question to configure QoS per your needs.

As I stated before, you need to implement MQC based QoS with policy maps inbound and outbound.

Switchport QoS trust is enabled by default and these isn't any mls qos related commands anymore.

QoS on newer platforms are similar to the behavior you would experience on a regular IOS router.

Regards,

Edison

10 REPLIES
Hall of Fame Super Bronze

QoS Turst for Cisco 4948E switch

4948E uses the same QoS concept as Sup6-E and Sup7-E as the ports are trusted by default.

QoS implementation is based on MQC, for more information please refer to the portion of the QoS document for the intended hardware:

http://www.cisco.com/en/US/docs/switches/lan/catalyst4500/12.2/54sg/configuration/guide/qos.html#wp1474085

Regards,

Edison

New Member

QoS Turst for Cisco 4948E switch

Hello Edson,

Thanks for the information. But that is not so clear as we think.

What I found is in the 4900 configuration guide for QoS. A note on QoS trust boundaries.

Cisco built the IOS for this switch considering that Cisco IP phone will wil be connected to the ports. but that is not always the case. On my case for example the customer has an AVAYA PBX - analog with an IP gateway.

So the sequence I found to apply on the interface to trust their marking is:

1- apply command: "switchport priority extend trust"

2 - apply command "cdp enable"

I am still waiting to test it. If you can test - please let me kow the results.

The frustration comes from the fact taht you expect something like "mls qos trust" or "qos trust dscp"

Thanks,

Gilson

Hall of Fame Super Bronze

QoS Turst for Cisco 4948E switch

I'm not sure what you find unclear. The QoS behavior has changed and the URL I posted indicates the hardware affected by this change. The 4900 switch is not the same platform/hardware as the 4948E switch.

You need to follow the documentation on the platform in question to configure QoS per your needs.

As I stated before, you need to implement MQC based QoS with policy maps inbound and outbound.

Switchport QoS trust is enabled by default and these isn't any mls qos related commands anymore.

QoS on newer platforms are similar to the behavior you would experience on a regular IOS router.

Regards,

Edison

New Member

QoS Turst for Cisco 4948E switch

Hi Edison,

You are correct about the MQC and the trust behavior of the 4948E. I will use the MQC and apply the policy I need.

But what still bugging me is the fact hat the 4948E I have only accepts the "qos control-packets" command instead of the normal qos command.

Thanks,

Gilson

Hall of Fame Super Bronze

QoS Turst for Cisco 4948E switch

Why would you need to modify L2 control packets?

QoS control-packets configuration is rarely needed.

For more info:

http://www.cisco.com/en/US/docs/switches/lan/catalyst4500/12.2/54sg/command/reference/int_sess.html#wp2167036

As I stated, you no longer use qos related command but instead you use class-map/policy-map combination.

Think of it as a router, not a switch.

Bronze

QoS Turst for Cisco 4948E switch

MachadoGB is completely right. The switch is marketed as server farm access switch, however , it uses completely different syntax for QOS as compared to C3750/C3750X or C3750G. From operational standpoint, this increases cost and only adds to confusion (just lost 1 day of figuring it out) and i am already getting questions from the Operational department "why can't i just put mls qos trust dscp on it". Furthermore, our servers are all untrusted by default, which matches fine with the previous model. Now we just introduced a switch where by default all is trusted...only adds to the confusion...

Super Bronze

Re: QoS Turst for Cisco 4948E switch

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Posting

gnijs wrote:

MachadoGB is completely right. The switch is marketed as server farm access switch, however , it uses completely different syntax for QOS as compared to C3750/C3750X or C3750G. From operational standpoint, this increases cost and only adds to confusion (just lost 1 day of figuring it out) and i am already getting questions from the Operational department "why can't i just put mls qos trust dscp on it". Furthermore, our servers are all untrusted by default, which matches fine with the previous model. Now we just introduced a switch where by default all is trusted...only adds to the confusion...

Laugh - darn Cisco for making changes.

Now if only CatOS and IOS and NX-OS were all exactly alike.

Now if only different Catalyst switch family features and configurations were all exactly alike (including QoS).

Now if only different IOS version features were all exactly alike.

But wait - it's not just Cisco, if the industry as whole would only stop making changes too.

I really never understood why punched cards fell out of favor, which is what I started with.  I even remember the extra time it took me to learn some of the new features of the IBM 129 card punch vs. the IBM 26 and 29 models, and the end result was still just a punched card.  It had some really confusing operational changes too, no physical program drum, didn't punch the card until you finished the whole card, a LED counter to indicate your current column.

I also so much preferred carrying my personal data files around on 2400' tapes (think I still got one in my closet) than these modern USB sticks too.  The latter are so much easier to mislay somewhere and not notice.  The former is also much more fun to watch in operation.  Lastly, the protect rings are much fun to toss across the office at coat hooks; try that with a USB stick.

So again laugh - of course there's issues with changes such as adding confusion, but are you really arguing depending how the switch is marketed or that you might lose a day figuring out some differences nothing shouldn't be changed?

Re: QoS Turst for Cisco 4948E switch

I also so much preferred carrying my personal data files around on 2400' tapes (think I still got one in my closet) than these modern USB sticks too.  The latter are so much easier to mislay somewhere and not notice.  The former is also much more fun to watch in operation.  Lastly, the protect rings are much fun to toss across the office at coat hooks; try that with a USB stick.

LOL @ dat

New Member

hi !!

hi !!

I am having a similar query related to QoS on 4948e and was googling when I found this forum.

I have to replace 3750 with 4948e. The " mls qos " & " mls qos trust dscp " defined on the 3750 are not applicable on 4948e. Hence I am looking for alternate commands for 4948e. Any help would be greatly appreciated.

Thanks !!

Re: QoS Turst for Cisco 4948E switch

Cisco is trying to make our lives easier by making it harder LOL

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