Cisco N5K-M1600 - Expansion Module - 6 Ports Troubleshooting Manual page 126

Registers and Counters
S e n d d o c u m e n t c o m m e n t s t o n e x u s 5 k - d o c f e e d b a c k @ c i s c o . c o m .
When troubleshooting FC performance problems, review the R_RDY, Link Reset, and Link Reset
Response counters. These help determine buffer to buffer credit problems that could lead to performance
issues.
Troubleshooting Fibre Channel forwarding issues
To troubleshoot Fibre Channel forwarding issues, it is important to know that GATOS is the
MAC/Forwarding ASIC on the Nexus 5000 switch. This section describes commands specific to this
ASIC.
Each Fibre Channel interface is assigned a GATOS number. To understand forwarding issues, you must
find the GATOS number for the specific FC interface.
Consider the following example:
switch# sh platform fwm info pif fc2/1
dump pif info: ifindex 0x1080000 dump_all 0 verbose 1
fc2/1: slot 1 port 0 state 0x0 pi_if 0x88bbb74 fwimpd ctx 0x889d4ec
fc2/1: oper_mode 0x1 rcvd_rbind: No
fc2/1: iftype 0x1
fc2/1: lif_blk(pi) 0x8523da4 vif_id_alloc_bmp 0x887360c
fc2/1: cfg_lif_blk_size 0 lif_blk_base(pi) 1922 lif_blk_size(pi) 1
fc2/1: cfg_lif_blk_size(pi) 0
fc2/1: if_flags 0x0 num_sub_lif_tbls 0 Num HIFs pinned 0
fc2/1 pd: lif_entries 1
fc2/1 pd: reverse ifmap lookup 'same' ifmap_idx 49
fc2/1: SAT_HIF Port?: No
In the following part of the example, notice that gatos_num 13 is the GATOS instance for Fibre Channel
interface 2/1:
fc2/1 pd: slot 1
fc2/1 pd: pif_type 'data fc'(2) hw_present 1
fc2/1 pd: fabric a info: voq 0-1
fc2/1 pd: fabric b info: voq 0-1
fc2/1 pd: subported 1 primary 1 atherton 0
fc2/1 pd: sup_src_dst_if 17
fc2/1 pd: policer info: uc (sel 2) mc (sel 1) bc (sel 0)
fc2/1 pd: mac-addr 000d.eca4.02b4
In the following part of the example, notice that the command also provides forwarding drop and discard
informatio:
fc2/1 pd: tx stats: bytes 4958178736 frames 36360131 discard 0 drop 0
fc2/1 pd: rx stats: bytes 2421909296 frames 36390924 discard 0 drop 0
You can also display GATOS errors for the GATOS instance that corresponds to the FC interface. In the
following part of the example, notice that the command only shows non-zero counters.
switch# show platform fwm info gatos-errors 13
Printing non zero Gatos error registers:
DROP_FCF_SW_VSAN_IDX_MISS: res0 = 60 res1 = 0
DROP_FCF_SW_DOMAIN_IDX_MISS: res0 = 489036 res1 = 0
DROP_FCF_SW_TBL_MISS: res0 = 489036 res1 = 0
DROP_NO_FABRIC_SELECTED: res0 = 489036 res1 = 0
DROP_VLAN_MASK_TO_NULL: res0 = 489036 res1 = 0
In the first of the two parts, drops and discards were described. Notice that the drop and discard counters
are separate for vEthernet and VFC interfaces. Review the output in the second example to help correlate
the reason for the drops.
Cisco Nexus 5000 Series Troubleshooting Guide
5-54
encap 0x5 bound_if? N #lifs 1 fwimpd ctx 0x88bd74c
if_map_idx 49 if_lid 33 if_fcoe_lid 34
logical port num 4 gatos_num 13
port_id 29 connected 1 up 1
port_id 29 connected 1 up 1
lif_blk 0-0
Chapter 5 Troubleshooting SAN Switching Issues
fwm_inst 0 fc 0
port map idx 49
OL-25300-01