Dell Networking PowerSwitch Layer 1 optical troubleshooting

This is for Layer 1 connectivity, if the link shows "up/up," but expected traffic is not passing, other configuration issues may be present.
 

Physical considerations

Verify that the transceivers and cables at both ends are seated properly and right side up.

Verify that the parts are compatible with each other. For example, single-mode fiber does not work in multi-mode transceivers.

Verify that transceivers and cables are in good working order. Do known-good components work when swapped in? Does it work if different device on the far end of the connection is used? A different, identically configured port on the switch?

Verify if transceivers are qualified for the switch and OS version in use. Dell support or sales can help verify if the transceivers are qualified. Dell does not guarantee that third party or unqualified optics work reliably, or at all. 

Configuration considerations

Port speed, negotiation, and FEC settings must match across the link. For example, if a server node is set to 10G with auto-negotiation off, the switch should match this. 

If unable to verify the settings on the far side, or if the link is not coming up, run through the available settings on the interface.

See the user guides for your OS version for exact command syntax, but here are some general guidelines:
 

SONiC:

soinc # configure terminal
sonic (conf)# interface Eth 1/1
sonic(conifg-if-Eth1/1)#  speed auto (default)
sonic(conifg-if-Eth1/1)#  no speed auto
sonic(conifg-if-Eth1/1)#   speed 10000

OS10: 
(note on the S5200F-ON and some Z series switches, speed changes through port-group settings, see https://www.dell.com/support/manuals/en-us/smartfabric-os10-emp-partner/smartfabric-os-user-guide-10-5-6/port-groups-on-s5200f-on-switches?guid=guid-1a9f6680-ab7e-4cfa-9c94-96cf3b436f8c&lang=en-us)
 

To check the current configuration of a port

OS10# show running-configuration interface ethernet 1/1/1
To change settings:
OS10:#  configure terminal
OS10(config)# interface ethernet 1/1/1
OS10(conf-if-eth1/1/1)# negotiation auto (default)
OS10(conf-if-eth1/1/1)# negotiation off (to disable auto-negotiation)
OS10(conf-if-eth1/1/1)# speed 10000 (to set speed manually)
OS10(conf-if-eth1/1/1)# speed auto (to set speed to auto-negotiate)

OS9:

To check the current configuration of a port:
OS9# show running-config interface tengigabitethernet 1/1
To change settings:
OS9# configure terminal
OS9 (config) # interface tengigabitethernet 1/1
OS9(conf-if-te-1/1) # negotiation auto (default)
OS9 (conf-if-te-1/1)# no negotiation auto (to disable auto-negotiation)
OS9(conf-if-te-1/1)# speed 1000 

OS6:

To check the current configuration on OS6:
OS6 # show running-config interface tengigabitethernet 1/0/1
To change settings:
OS6 # configure terminal
OS6 (config)) interface tengigabitethernet 1/0/1
OS6 (conifg-if-Te1/0/1)# speed 10000

FEC settings:

It is sometimes necessary to manually set FEC settings, though usually the default "auto" mode is sufficient. This setting must match across the link. This only applies to 25G, 50G, or 100G Ethernet interfaces.

SONiC:

sonic(config)# interface Eth1/2
sonic(config-if-Eth1/2)# fec [option]

Available options:

auto — Automatically detects an installed transceiver and configures the correct FEC type on a port.
FC — Enables FEC type FC on supported interfaces. FC stands for fire code.
RS — Enables FEC type RS on supported interfaces. RS stands for Reed-Solomon code.
none — Disables FEC on an interface.

OS10:

OS10(config)# interface ethernet 1/1/41
OS10(conf-if-eth1/1/41)# fec [option]

Available options:

CL74-FC—Supports 25G and 50G
CL91-RS—Supports 100G
CL108-RS—Supports 25G and 50G
CL119-RS—Supports 400G
off—Disables FEC

OS9:

OS9(configure)#  interface hu 1/1

OS9(conf-if-hu-1/1)#fec enable

OS6:

OS6 (conifg-if-Tw1/0/1)# forward-error-correction [option]

Available options:

disable-fec              Disable FEC
enable-fec-cl108         Enable CL108/RS FEC
enable-fec-cl74          Enable CL74/Base-R FEC
enable-fec-cl91          Enable CL91/RS FEC
inherit                  Inherit FEC