Configurations vary for different types of policies, that is, default system level policy and interface level custom policies
for different speeds, as follows:
-
Default System Level Policy for FCoE
switch(config)# system qos
switch(config-sys-qos)# service-policy type network-qos default-fcoe-nq-policy
switch(config-sys-qos)# service-policy type queuing input default-fcoe-in-que-policy
switch(config-sys-qos)# service-policy type queuing output default-fcoe-out-policy
The default settings for system level policy for FCoE are as follows:
-
Buffer-size - 104000
-
Pause-threshold - 20800
-
Resume-threshold - 19136
-
Interface Level Custom Policies for Different Speeds
Custom policies for long distance that need to be applied to Ethernet port/port channel bound to VFC/VFC-PO ISLs with long
distance support are as follows:
-
Long Distance Policy for 10G ISLs
switch(config)# policy-map type queuing ld_10G_fcoe_in_que_policy
switch(config-pmap-que)# class type queuing c-in-q1
switch(config-pmap-c-que)# bandwidth percent 90
switch(config-pmap-c-que)# pause buffer-size 166400 pause-threshold 20800 resume-threshold 19136
switch(config-pmap-c-que)# class type queuing c-in-q-default
switch(config-pmap-c-que)# bandwidth percent 10
switch(config-pmap-c-que)
switch(config)# policy-map type queuing ld_10G_fcoe_in_que_policy
switch(config-pmap-que)# class type queuing c-in-q1
switch(config-pmap-c-que)# bandwidth percent 90
switch(config-pmap-c-que)# pause buffer-size 291200 pause-threshold 145600 resume-threshold 143936
switch(config-pmap-c-que)# class type queuing c-in-q-default
switch(config-pmap-c-que)# bandwidth percent 10
-
Long Distance Policy for 25G ISLs
switch(config)# policy-map type queuing ld_25G_fcoe_in_que_policy
switch(config-pmap-que)# class type queuing c-in-q1
switch(config-pmap-c-que)# bandwidth percent 90
switch(config-pmap-c-que)# pause buffer-size 384800 pause-threshold 20800 resume-threshold 19136
switch(config-pmap-c-que)# class type queuing c-in-q-default
switch(config-pmap-c-que)# bandwidth percent 10
switch(config-pmap-c-que)#
switch(config)# policy-map type queuing ld_25G_fcoe_in_que_policy
switch(config-pmap-que)# class type queuing c-in-q1
switch(config-pmap-c-que)# bandwidth percent 90
switch(config-pmap-c-que)# pause buffer-size 728000 pause-threshold 364000 resume-threshold 362336
switch(config-pmap-c-que)# class type queuing c-in-q-default
switch(config-pmap-c-que)# bandwidth percent 10
switch(config-pmap-c-que)#
-
Long Distance Policy for 40G ISLs
switch(config)# policy-map type queuing ld_40G_fcoe_in_que_policy
switch(config-pmap-que)# class type queuing c-in-q1
switch(config-pmap-c-que)# bandwidth percent 90
switch(config-pmap-c-que)# pause buffer-size 728000 pause-threshold 78208 resume-threshold 76544
switch(config-pmap-c-que)# class type queuing c-in-q-default
switch(config-pmap-c-que)# bandwidth percent 10
switch(config-pmap-c-que)#
switch(config)# policy-map type queuing ld_40G_fcoe_in_que_policy
switch(config-pmap-que)# class type queuing c-in-q1
switch(config-pmap-c-que)# bandwidth percent 90
switch(config-pmap-c-que)# pause buffer-size 1299584 pause-threshold 649792 resume-threshold 648128
switch(config-pmap-c-que)# class type queuing c-in-q-default
switch(config-pmap-c-que)# bandwidth percent 10
switch(config-pmap-c-que)#
Custom Policy for Ingress Buffer Size and Pause/Resume Thresholds
If sufficient buffers are not available to bring up long-distance ports, then fine tuning the buffers allocated to any 10G/25G
Ethernet ports (with short distance requirements, that is, less than 100 meters) using default policies is required. If sufficient
buffers are not available to bring up long-distance ports, a buffer allocation failure message appears. A sample buffer allocation
failure message is as follows:
switch(config-if)# interface ethernet1/8
switch(config-if)# service-policy type queuing input ld_10G_fcoe_in_que_policy
switch(config-if)# no shutdown
2022 Oct 31 07:39:21 HW1 %$ VDC-1 %$ %ACLQOS-SLOT1-2-ACLQOS_FAILED: ACLQOS failure: Ingress buffer allocation failed for interface Ethernet1/8
Create a custom policy to free up the required buffers and apply it to the existing Ethernet ports or to Ethernet ports bound
for VFC that is used for short distance connectivity.
switch(config)# policy-map type queuing 100m_fcoe_in_que_policy
switch(config-pmap-que)# class type queuing c-in-q1
switch(config-pmap-c-que)# bandwidth percent 50
switch(config-pmap-c-que)# pause buffer-size 41600 pause-threshold 20800 resume-threshold 19136
switch(config-pmap-c-que)# class type queuing c-in-q-default
switch(config-pmap-c-que)# bandwidth percent 50
switch(config-pmap-c-que)#
Required number of Ethernet Ports to Reduce Ingress Buffers on per Long Distance FCoE ISL
The following table displays the number of Ethernet ports needing an ingress buffer size reduction to accommodate a single
long distance FCoE ISL of a given speed.
Table 2. Recommendation to Reduce Ingress Buffer Size
Speed
|
Recommendation
|
10G long distance ISL
|
Apply 100m_fcoe_in_que_policy on one 10G/25G port
|
25G long distance ISL
|
Apply 100m_fcoe_in_que_policy on five 10G/25G ports
|
40G long distance ISL
|
Apply 100m_fcoe_in_que_policy on nine 10G/25G ports
|