Hello, I have worked for years somewhere QoS wasn't used, and now I have to relearn it.
Firtst, RTFM, then I'm doing a small lab with 2 identical 2960 (LAN Lite, 8 ports) with a single trunk to try it out.
I was trying to make vlan 4 behave as "best effort" and vlan 2 have priority on the trunk. I was hoping to force CoS 5 on vlan 2 traffic then expedite egress queue 1 on the trunk interface.
That didn't work, traffic from SwitchA vlan 4 to SwitchB vlan 4 (going through the trunk fa0/8) can saturate the trunk at 100Mbps, but SwitchA vlan 2 to SwitchB vlan 2 has it's bandwith limited to 4Mbps whether the trunk is saturated or not.
I am clearly missiong something, but I have read the full doccument, can anyone find a clue with the folloing info? Thank you.
Drawing: Host1--(fa0/6)-SwitchA-(trunk-fa0/8)-SwitchB--(fa0/6)-Host3
Host2--(fa0/7)----| |----(fa0/7)-Host4
Both SwitchA and SwitchB have identical configs:
mls qos
!
interface FastEthernet0/6
switchport access vlan 4
switchport mode access
!
interface FastEthernet0/7
switchport access vlan 2
switchport mode access
mls qos cos 5
mls qos cos override
!
interface FastEthernet0/8
switchport mode trunk
priority-queue out
mls qos trust cos
!
Show:
#show mls qos input-queue
Queue : 1 2
----------------------------------------------
buffers : 90 10
bandwidth : 4 4
priority : 0 10
threshold1: 100 100
threshold2: 100 100
#show mls qos maps
Cos-outputq-threshold map:
cos: 0 1 2 3 4 5 6 7
------------------------------------
queue-threshold: 2-1 2-1 3-1 3-1 4-1 1-1 4-1 4-1
Cos-inputq-threshold map:
cos: 0 1 2 3 4 5 6 7
------------------------------------
queue-threshold: 1-1 1-1 1-1 1-1 1-1 2-1 1-1 1-1
#show mls qos interface
FastEthernet0/6
trust state: not trusted
trust mode: not trusted
trust enabled flag: ena
COS override: dis
default COS: 0
FastEthernet0/7
trust state: cos override
trust mode: cos override
trust enabled flag: ena
COS override: ena
default COS: 5
FastEthernet0/8
trust state: trust cos
trust mode: trust cos
trust enabled flag: ena
COS override: dis
default COS: 0
#show mls qos interface queueing
FastEthernet0/6
Egress Priority Queue : disabled
Shaped queue weights (absolute) : 25 0 0 0
Shared queue weights : 25 25 25 25
The port bandwidth limit : 100 (Operational Bandwidth:100.0)
The port is mapped to qset : 1
FastEthernet0/7
Egress Priority Queue : disabled
Shaped queue weights (absolute) : 25 0 0 0
Shared queue weights : 25 25 25 25
The port bandwidth limit : 100 (Operational Bandwidth:100.0)
The port is mapped to qset : 1
FastEthernet0/8
Egress Priority Queue : enabled
Shaped queue weights (absolute) : 25 0 0 0
Shared queue weights : 25 25 25 25
The port bandwidth limit : 100 (Operational Bandwidth:100.0)
The port is mapped to qset : 1
