How to check if the physical port is healthy in a Nexus 5K switch?

[jonathan.maxwell]

Hello.

I am trying to determine the source of strange port behavior in a Nexus 5K switch.

How can I check the physical health of a port in a Nexus 5K switch, to determine that the issue is not at the physical layer?

Thank you.

[balaji.bandi]

chcek example as below : more focus on BOLD ( also check the logs)

Ethernet1/11 is up
Dedicated Interface
Hardware: 1000/10000 Ethernet, address: xxxxxxxxxxxxxxxxx
MTU 1500 bytes, BW 10000000 Kbit,, BW 10000000 Kbit, DLY 10 usec
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, medium is broadcast
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
....................
RX
386318618327 unicast packets 537720739 multicast packets 86264875 broadcast packets
386942603941 input packets 373395782816355 bytes
185179238111 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
167655430355 unicast packets 950319154 multicast packets 1717232076 broadcast packets
170322981585 output packets 168070865867612 bytes
79824980751 jumbo packets
0 output error 0 collision 0 deferred 0 late collision
0 lost carrier 0 no carrier 0 babble 0 output discard
0 Tx pause

[jonathan.maxwell]

Thank you for this.

I am looking for something more in depth that will verify that the hardware in the port is healthy.

I understand that there is a "show test" command in which I must first perform a reboot.

"Show controllers" Could prove useful, bit I do not understand the data.

Do you have any suggestions? 

Thank you.

[balaji.bandi]

I am trying to determine the source of strange port behavior in a Nexus 5K switch.

i would hav asked first instance, what kind of strange, give example ?

I am looking for something more in depth that will verify that the hardware in the port is healthy.

what kind of depth level you want to test, is ths live environment or Lab ?

[jonathan.maxwell]

Thank you for your comments. From these comments I conclude that if I use basically all the commands here, I can conclude the port is physically healthy.

I have a Nexus 5k cluster connected to a FEX, some FEX ports are showing flapping, and the FEX uplink link is showing extremely many jumbo packets. the MTU is 1500. ports on all circuit devices are duplex auto. I wanted to rule out physical port malfunction. 

[balaji.bandi]

I have a Nexus 5k cluster connected to a FEX, some FEX ports are showing flapping, and the FEX uplink link is showing extremely many jumbo packets. the MTU is 1500. ports on all circuit devices are duplex auto. I wanted to rule out physical port malfunction.

Flapping means going up and down ? what Logs you see on the switches ?

can give some output information to understand the issue ?

[Reza Sharifi · Accepted solution]

If you are looking to check the health of an interface in real-time e.g., 

monitor interface (interface-name | traffic)in Juniper world

Cisco cli does not have that.

In addition to what BB provided, you can also use these 2 commands to see the optic and the interface's health.

show interface ex/x capabilities

show interface ex/x transceiver sprom

HTH

[Reza Sharifi]

There is also a diagnostic command (see link) that can be run at boot time, but obviously, that will require a reboot first, which is probably not what you are looking for.

https://www.cisco.com/c/en/us/td/docs/switches/datacenter/nexus5000/sw/system_management/b_Cisco_Nexus_5000_Series_NX-OS_System_Management_Configuration_Guide/Cisco_Nexus_5000_Series_NX-OS_System_Management_Configuration_Guide_chapter6.pdf

Also, if there is FEX involved. here is a command that shows the FEX port in detail. 

sh fex xx detail

There is also a command you can use to logon to a FEX, check the ports, and run diagnostics, but I can't recall it right now.

HTH