Hi there!
There is a problem as follows.
I have Nexus 5548UP with SAN attached to FC-port and UCS 200 M2 attached by CNA to Ethernet port. FCoE is configured and operational. FC port is 8Gbps, Ethernet is 10G. UCS is discless and boots from the SAN. Same time UCS attaches external storage by iSCSI via the same CNA. FCoE traffic is tagged with CoS#3 on the egress of CNA. QoS is configured as follows:
class-map type qos class-fcoe
class-map type queuing class-fcoe
match qos-group 1
policy-map type qos iSCSI
class class-fcoe
set qos-group 1
class class-default
set qos-group 0
policy-map type queuing iSCSI-que-in
class type queuing class-fcoe
bandwidth percent 50
class type queuing class-default
bandwidth percent 50
policy-map type queuing iSCSI-que-out
class type queuing class-fcoe
bandwidth percent 50
class type queuing class-default
bandwidth percent 50
policy-map type network-qos MyQoS
class type network-qos class-fcoe
pause no-drop
mtu 2158
class type network-qos class-default
mtu 9216
multicast-optimize
system qos
service-policy type network-qos MyQoS
interface Ethernet1/19
! link to UCS
service-policy type qos input iSCSI
service-policy type queuing input iSCSI-que-in
service-policy type queuing output iSCSI-que-out
untagged cos 0
interface Ethernet1/22
! link to iSCSI storage
service-policy type qos input iSCSI
service-policy type queuing input iSCSI-que-in
service-policy type queuing output iSCSI-que-out
Now I observe increment of discarded FCoE frames on E1/19 ingress:
N5548-TOP# sh queuing int e1/19
Ethernet1/19 queuing information:
TX Queuing
qos-group sched-type oper-bandwidth
0 WRR 50
1 WRR 50
RX Queuing
qos-group 0
q-size: 360960, HW MTU: 9216 (9216 configured)
drop-type: drop, xon: 0, xoff: 360960
Statistics:
Pkts received over the port : 2276
Ucast pkts sent to the cross-bar : 2096
Mcast pkts sent to the cross-bar : 180
Ucast pkts received from the cross-bar : 4284
Pkts sent to the port : 384253
Pkts discarded on ingress : 0
Per-priority-pause status : Rx (Inactive), Tx (Inactive)
qos-group 1
q-size: 79360, HW MTU: 2158 (2158 configured)
drop-type: no-drop, xon: 20480, xoff: 40320
Statistics:
Pkts received over the port : 586845
Ucast pkts sent to the cross-bar : 510070
Mcast pkts sent to the cross-bar : 0
Ucast pkts received from the cross-bar : 232683
Pkts sent to the port : 232683
Pkts discarded on ingress : 76775
Per-priority-pause status : Rx (Inactive), Tx (Inactive)
Total Multicast crossbar statistics:
Mcast pkts received from the cross-bar : 379969
N5548-TOP# sh queuing int e1/19
Ethernet1/19 queuing information:
TX Queuing
qos-group sched-type oper-bandwidth
0 WRR 50
1 WRR 50
RX Queuing
qos-group 0
q-size: 360960, HW MTU: 9216 (9216 configured)
drop-type: drop, xon: 0, xoff: 360960
Statistics:
Pkts received over the port : 2281
Ucast pkts sent to the cross-bar : 2099
Mcast pkts sent to the cross-bar : 182
Ucast pkts received from the cross-bar : 4295
Pkts sent to the port : 386709
Pkts discarded on ingress : 0
Per-priority-pause status : Rx (Inactive), Tx (Inactive)
qos-group 1
q-size: 79360, HW MTU: 2158 (2158 configured)
drop-type: no-drop, xon: 20480, xoff: 40320
Statistics:
Pkts received over the port : 590483
Ucast pkts sent to the cross-bar : 513217
Mcast pkts sent to the cross-bar : 0
Ucast pkts received from the cross-bar : 232713
Pkts sent to the port : 232713
Pkts discarded on ingress : 77266
Per-priority-pause status : Rx (Inactive), Tx (Inactive)
Total Multicast crossbar statistics:
Mcast pkts received from the cross-bar : 382414
What the reason of discard could be?
