Cisco ASR920 traffic shaping and policing fair-queue

[BasV]

Hello,

We have a Cisco ASR920 router which is connected to our ISP 500Mbps (both up and down) connection on port GigabitEthernet0/0/11.

On our LAN side we have multiple customers, all with their own IP. We currently set up some basic traffic shaping and policing with the intention that one customer can never take up the full 500Mbps and cause packet loss or connection issues for other customers.

We currently set it up like this:

policy-map shaping-isp
 class class-default
  shape average 524288000   
policy-map policing-isp
 class class-default
  police 524288000 conform-action transmit  exceed-action drop 

interface GigabitEthernet0/0/11
 description ISP
 ip address ***.***.***.*** ***.***.***.***
 media-type rj45
 negotiation auto
 service-policy input policing-isp
 service-policy output shaping-isp
!

However, now I do see regular packet loss, even if the internet usage is between 50 and 100 Mbps.

I also tried to add "fair-queue" to the class class-default on both policy-maps, it however doesn't recognise the command.

Please advise me in how I should set this up properly, and what my issue can be.

Regards,

Bas

[BasV]

Hello,

Thanks for your response. Sorry if I wasn't clear but the fair-queue command is not accepted, that's what I mean by it's not working:

RT01(config-pmap-c)#fair-queue
                    ^
% Invalid input detected at '^' marker.

Any idea why that is? Maybe it's not supported on the ASR920....?

Regards,

Bas

[Joseph W. Doherty]

It's possible FQ is not supported on an ASR920.  What IOS is your ASR920 running?

BTW, queuing commands, like FQ, would not be acceptable for an ingress policy.  Policy you tried to apply FQ on isn't, anywhere, defined for ingress usage, correct?

Post results for:

conf t
policy-map sample
class class-default
?

[BasV]

Hello,

In the mean time I heard from Cisco support that fair queue is not supported on the ASR920 indeed. I'm running IOS XE version 16.12.04.

Hereby the options of class-default under a new sample policy:

RT01(config-pmap-c)#?
Policy-map class configuration commands:
  bandwidth       Bandwidth
  exit            Exit from class action configuration mode
  no              Negate or set default values of a command
  police          Police
  priority        Strict Scheduling Priority for this Class
  queue-limit     Queue Max Threshold for Tail Drop
  random-detect   Enable Random Early Detection as drop policy
  service-policy  Configure QoS Service Policy
  set             Set QoS values
  shape           Traffic Shaping

Regards,

Bas

[Joseph W. Doherty]

No FQ, interesting!  It's one of Cisco's best QoS features.

Hmm, I wonder if the platform supports the old interface (direct) FQ and/or shape commands.  Probably not as both were drop, after a while, because CBWFQ offers them.

Thanks for the info.