Dec 2019

I purchased some SFPs to go in to a Cisco 10GB switch, and found they did not work in my switch. While investigating the fault, I found some useful commands to help me.

These commands seem to work on both Cisco IOS and the Nexus switches, alebit with some slightly different syntax.

Show Inventory - sh inventory displays information about the switch hardware options:

NAME: "Chassis", DESCR: "Nexus 3548 Chassis"
PID: N3K-C3548P-10G    , VID: V02 , SN: FOC1822R0WS

NAME: "Module 1", DESCR: "48x10GE Supervisor"
PID: N3K-C3548P-10G    , VID: V02 , SN: FOC18220S2A

NAME: "Fan 1", DESCR: "Chassis fan module"
PID: NXA-FAN-30CFM-F   , VID: N/A , SN: N/A

NAME: "Fan 2", DESCR: "Chassis fan module"
PID: NXA-FAN-30CFM-F   , VID: N/A , SN: N/A

NAME: "Fan 3", DESCR: "Chassis fan module"
PID: NXA-FAN-30CFM-F   , VID: N/A , SN: N/A

NAME: "Fan 4", DESCR: "Chassis fan module"
PID: NXA-FAN-30CFM-F   , VID: N/A , SN: N/A

NAME: "Power supply 1", DESCR: "AC power supply"
PID: N2200-PAC-400W    , VID: V04 , SN: DTN1817P5GC

NAME: "Power supply 2", DESCR: "AC power supply"
PID: N2200-PAC-400W    , VID: V04 , SN: DTN1817P5Q1

Show Interface displays detailed information about each interface. If you only issue the command sh interface (Nexus) (or sh interfaces for IOS) then you get information regarding all interfaces.

You can get information on a specific interface by using the Cisco syntax sh interface ethernet 1/1. In this example we get the information for port 1. Depending on your switch you might have to use ethernet or GigabitEthernet etc.

Ethernet1/1 is up
 Dedicated Interface
  Hardware: 100/1000/10000/40000 Ethernet, address: 88f0.31ca.b0c8 (bia 88f0.31c
a.b0c8)
  MTU 1500 bytes, BW 10000000 Kbit, DLY 10 usec
  reliability 255/255, txload 1/255, rxload 1/255
  Encapsulation ARPA
  Port mode is access
  full-duplex, 10 Gb/s, media type is 10G
  Beacon is turned off
  Input flow-control is off, output flow-control is off
  Rate mode is dedicated
  Switchport monitor is off
  EtherType is 0x8100
  Last link flapped 00:14:47
  Last clearing of "show interface" counters never
  5 interface resets
  30 seconds input rate 24 bits/sec, 0 packets/sec
  30 seconds output rate 296 bits/sec, 0 packets/sec
  Load-Interval #2: 5 minute (300 seconds)
    input rate 192 bps, 0 pps; output rate 360 bps, 0 pps
  RX
    0 unicast packets  115 multicast packets  34 broadcast packets
    149 input packets  22045 bytes
    0 jumbo packets  0 storm suppression bytes
    0 runts  0 giants  0 CRC  0 no buffer
    0 input error  0 short frame  0 overrun   0 underrun  0 ignored
    0 watchdog  0 bad etype drop  0 bad proto drop  0 if down drop
    0 input with dribble  0 input discard
    0 Rx pause
  TX
    520 unicast packets  0 multicast packets  0 broadcast packets
    520 output packets  49544 bytes
    0 jumbo packets
    0 output errors  0 collision  0 deferred  0 late collision
    0 lost carrier  0 no carrier  0 babble 0 output discard
    0 Tx pause

Show Interface Status will display a summary of interfaces and their status. Use either sh interface status to show all interfaces, or sh interface ehternet 1/1 status to show specific interface.

--------------------------------------------------------------------------------
Port          Name               Status    Vlan      Duplex  Speed   Type
--------------------------------------------------------------------------------
Eth1/1        --                 connected 1         full    10G     Unknown Typ
Eth1/2        --                 sfpAbsent 1         full    10G     --
Eth1/3        --                 sfpAbsent 1         full    10G     --
Eth1/4        --                 sfpAbsent 1         full    10G     --