TOS based Queue Distribution Configuration
This feature allows both type of configuration (precedence or DSCP). Before the implementation of this feature only allows DSCP profiles.The most significant three bits of the DSCP are Class Selector bits, which provides backward compatibility with ip precedence.
We will utilize these DSCP bits to set Precedence. For example when user configure Precedence 101 in CLI, we just need to convert this value to DSCPs(101000 ~ 101111), then normally set the DSCP.
Indicate the standards to be imposed or other all-embracing blanket requirements.
On the basis of already existing DSCP profiles, new precedence profiles are introducing as qos map-profile in this chapter.
The working on these precedence profile is similar to that of DSCP but now we can permit both the configurations according to our requirement.
There are 2 Qos-map Precedence profiles introduced:
• Precedence-to-queue
• Precedence-to-precedence
Precedence-to-queue
This is an ingress profile similar to dscp-to-queue. This profile will map precedence value 0-7 to queue 0-7.
Topology
Precedence-to-queue topology
Configuration
Basic configuration
#configure terminal | Enter configure mode |
(config)#enable qos | Enable Qos |
(config)#exit | Exit configure mode |
(config)# qos profile precedence-to-queue Prec1_que1 | Configure qos-map profile precedence-to-queue with Profile name as Prece1_que1 |
(config-ingress-prec-map)# precedence 1 queue 2 | Configure mapping of prece 1 to queue 2, so that traffic with precedence 1 should take queue as q2 |
(config)#exit | Exit configure mode |
(config)# interface xe1 | Configure ingress interface xe1 |
(config-if)#qos map-profile precedence-to-queue Prec1_que1 | Map the profile Prec1_que1 to interface xe1 so that ingress traffic hitting the xe1 interface with prece as 1 should take queue q2 |
(config-if)#commit | Commit the configuration |
(config-if)#end | Exit the configuration. |
Validation
#show run int xe1
!
interface xe1
qos map-profile precedence-to-queue Prec1_que1
!
#show qos-profile type precedence-to-queue
profile name: Prec1_que1
profile type: precedence-to-queue
profile attached to 1 instances
configured mapping:
precedence 1 queue 2
Detailed mapping:
-------+------------------
INPUT | OUTPUT
-------+------------------
PREC | Queue | Out PREC
-------+-------+----------
0 0 0
1 1 2
2 2 0
3 3 0
4 4 0
5 5 0
6 6 0
7 7 0
R1#show run qos
qos enable
!
qos profile precedence-to-queue Prec1_que1
precedence 1 queue 2
!
interface xe1
qos map-profile precedence-to-queue Prec1_que1
!
Precedence-to-precedence
This is an egress profile similar to dscp-to-dscp. This profile will map precedence value 0-7 to precedence value 0-7. It will change the egress queue according to new mapped precedence value.
Topology
Precedence-to-precedence topology
Basic configuration
#configure terminal | Enter configure mode |
(config)#enable qos | Enable Qos |
(config)#exit | Exit configure mode |
(config)# qos profile precedence-to-precedence prec_prec2 | Configure qos-map profile precedence-to-precedence with Profile name as prec_prec2 |
(config-ingress-prec-map)# precedence 2 precedence 5 | Configure mapping of prece 2 to precedence 5, so that traffic with precedence 2 should remark to precedence 5 and should take corresponding queue q5 on next DUT |
(config)#exit | Exit configure mode |
(config)# interface xe2 | Configure ingress interface xe2 |
(config-if)#qos map-profile precedence-to-queue prec_prec2 | Map the profile prec_prec2 to egress interface xe2 of 1st node. |
(config-if)#commit | Commit the configuration |
(config-if)#end | Exit the configuration. |
Valodation
#show run qos
qos enable
!
qos profile precedence-to-precedence prec_prec2
precedence 2 precedence 5
!
!
!
!
interface xe2
qos map-profile precedence-to-precedence prec_prec2
!
#show qos-profile prec_prec2
profile name: prec_prec2
profile type: precedence-to-precedence
profile attached to 1 instances
configured mapping:
precedence 2 precedence 5
Detailed mapping:
-------+--------
INPUT | OUTPUT
-------+--------
PREC | PREC
-------+--------
0 0
1 1
2 5
3 3
4 4
5 5
6 6
7 7