IOS-XE: Disable auto QOS, Enable manual QOS

[Dean Romanelli]

Hi All,

I have a network of 4 traditional catalyst 2960 switches connected to 1 core 3650 switch running IOS-XE.  My CCNP switch books says "never implement auto qos in conjunction with manual QOS."  However, I am in a position where I must use manual QOS.  Problem is, on the IOS-XE switch, there is no way to trust the DSCP (which I need) on a port other than "auto qos trust dscp," and running that command enables auto qos across the switch.  I see I can run the command "no auto qos srnd4" and that will disable it, but I don't think it allows me to then run the mls qos command and set everything up manually.

Any thoughts on how to solve this? I supposed instead of trusting the ports I could configure my own service policies to re-tag the packets with the right markings, but then with QOS disabled, the map table and queues won't be there.  Or I could just run it together with manual and cross my fingers.

[Rolf Fischer · Accepted solution]

Hi Dean,

I'm not sure if I understand the question correctly but trust DSCP is enabled by default on the 3560's wired ports and no additional configuration is required.

Link: c3650 QoS CG Trust Behavior

HTH

Rolf

[Dean Romanelli]

That will work.

Thank you Sir.

[mpctxc2011]

Rolf,

Does the default trust for DSCP include the trunked uplink ports?

[Rolf Fischer]

Hi,

follow the link in my first post and have a look at table 9 (Trust and Queuing Behavior):

Incomming Packet: Tagged => Trust Behavoir: Preserve DSCP and CoS; Queuing based on DSCP.

HTH
Rolf