Cisco Support Community
cancel
Showing results for 
Search instead for 
Did you mean: 
New Member

QoS priority in ios-xr

If i configured qos in below way in ios-xr:

policy-map test
 class class1
  shape average 100 mbps
  !
 class class2
  shape average 200 mbps
 !
 class class3
shape average 50 mbpss
  !
 class class4
  bandwidth remaining percent 90
 !
 class class-default
  bandwidth remaining percent 10
 !
 end-policy-map


if the interface is 1Gbps and below traffic is on egress interface at below rate:

class1: 200mbps

class2: 200mbps

class3:100mbps

class4: 800mbps

what will be the output? will the class1,2,3 get the defined bandwidth? if found class1,2,3 are getting dropped before the defined limit and class 4 is eating all bandwidth.Is it normal? i know that we can define priority level but if we don not define it, id the defined output is normal?

Everyone's tags (1)
1 ACCEPTED SOLUTION

Accepted Solutions
Cisco Employee

yeah you probably want to set

yeah you probably want to set this up a bit differently.

you would want to use the bandwidth command in these shaped classes.

the shape command (setting PIR) operate a bit differently then the classes that have the bandwidth command  set (setting cIR).

the CIR of a shape policy is 64k, so after the 64k is served, it moves over to the other classes, gets

the bw remaining assigned and then what is left is divided over the hsaped classes to the max of their PIR.

If you set the bandwidth on all classes you "reserve" that bandwidth on that class when that bw is needed.

may wanna pull cisco live form years 2013 and 2014 (orlando/sanfran) session ID 2904 for more details on QOS you may like.

regards

xander

Xander Thuijs CCIE #6775 Principal Engineer ASR9000, CRS, NCS6000 & IOS-XR
1 REPLY
Cisco Employee

yeah you probably want to set

yeah you probably want to set this up a bit differently.

you would want to use the bandwidth command in these shaped classes.

the shape command (setting PIR) operate a bit differently then the classes that have the bandwidth command  set (setting cIR).

the CIR of a shape policy is 64k, so after the 64k is served, it moves over to the other classes, gets

the bw remaining assigned and then what is left is divided over the hsaped classes to the max of their PIR.

If you set the bandwidth on all classes you "reserve" that bandwidth on that class when that bw is needed.

may wanna pull cisco live form years 2013 and 2014 (orlando/sanfran) session ID 2904 for more details on QOS you may like.

regards

xander

Xander Thuijs CCIE #6775 Principal Engineer ASR9000, CRS, NCS6000 & IOS-XR
166
Views
0
Helpful
1
Replies
CreatePlease to create content