Hello all. I've been tasked with applying QOS for the first time in our organisation. I believe I've come up with a solution, elegant or not, and would really appreciate any feedback or suggestions.
Background: We have two microwave links that carry separate vlans. Each vlan is assigned a priority on a given link s/t QOS is really only required when a link fails. Should this occur the following requirements need to be met:
a) rapid failover for the vlans on the downed link to the operational link
b) preferential service is now required as a single link can not service all traffic without congestion.
| |
------ | | Link1 (45Mb) Link2(155Mb) | | | | | | |
------ | |
The second 2970 along Link1 is for access/emergency work at a remote relay location. Link2's traffic does not traverse 2970_2.
We have 3 classes of traffic which conveniently enter the 2970 network from 3 .1q links from the 7609 and the 3550. Voice, Internal/Critical, and Regular Inet. We may eventually carry all traffic from a single link and push classification out to the 3550 and the 7609.
On both 2970_1 and 2970_3 the relevant configs for the 3 classes of traffic entering the network:
interface GigabitEthernet0/3 description Voice switchport trunk encapsulation dot1q switchport trunk allowed vlan 100 switchport mode trunk speed 100 duplex full priority-queue out mls qos cos 5 mls qos cos override spanning-tree portfast spanning-tree bpdufilter enable ! interface GigabitEthernet0/5 description Internal/Criticall switchport trunk encapsulation dot1q switchport trunk allowed vlan 101,200 switchport mode trunk speed 100 duplex full mls qos cos 2 mls qos cos override spanning-tree portfast spanning-tree bpdufilter enable ! interface GigabitEthernet0/7 description Inet switchport trunk encapsulation dot1q switchport trunk allowed vlan 250 switchport mode trunk speed 100 duplex full mls qos cos override spanning-tree portfast spanning-tree bpdufilter enable
The 2970's run rapid-pvst. How can I assure any topology changes down the line will not effect rapid convergence between these two links? (For example, another switch running pvst+. Will the command bpdufilter enable on all ingress ports assure the 2970 network remains in rapid-pvst mode?)
For scheduling on the two p2p links the relevant configs for the
2970_1 and 2970_3 are as follows:! interface GigabitEthernet0/12 description Egress 45Mbit - 50% Internal, 25% Inet, 25% Other switchport trunk encapsulation dot1q switchport mode trunk bandwidth 45 speed 100 duplex full srr-queue bandwidth share 1 1 2 1 priority-queue out mls qos trust dscp ! interface GigabitEthernet0/24 description Egress 155Mbit - 50% Critical, 25% Inet, 25% Other switchport trunk encapsulation dot1q switchport mode trunk speed 1000 duplex full srr-queue bandwidth share 1 1 2 1 srr-queue bandwidth limit 16 priority-queue out mls qos trust dscp
So with default mls qos cos mappings I hope to obtain the requirement of strict priority scheduling for voice traffic, 50% for Internal/Critical data, and 25% for Inet, 25% for other.
Will this work? Any gotchas that I'm missing? Thanks all!