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Optical monitoring not possible on ports with link down?

Contributor III

Am I missing something or the optical monitoring only works when the link is up? I am trying to troubleshoot some fiber connections which were unreliable / not coming up and when I use the `show optical-monitor x/y/z` command, I get nothing. Just comes back to the prompt.

If the same port with the same optical module has link, then I do get a proper readout of the optical monitor command (tx power / rx power / temps / current).

Being able to monitor a non-working link is a pretty basic thing to do to be honest and having access to DDM/DOM/optical monitoring of down links lets you figure out if you have, for example, a broken fiber in one direction, a mis-plugged rx/tx pair, etc.

Is there any way to monitor the DDM/optical parameters while the link is down?

Thanks in advance!


RUCKUS Team Member

Hi Diego,

The optical monitor shows signal levels, but will only show statistics if the port is up:

device(config)# show optic 2/1/1
Port Temperature Tx Power Rx Power Tx Bias Current
2/1/1 32.2578 C -002.5157 dBm -002.8091 dBm 5.966 mA
Normal Normal Normal Normal

If Signal is not correct and media type and fiber not right type link will not come up.
You need to check show media e x/y/z on both side make sure fiber is of right type.

Hope this helps.

If you need further help please open a  ticket and work with our TAC team.



View solution in original post


Hello Hashim,

I tried everything but still not working.

below are the configs did:

#sh conf
Startup-config data location is flash memory
Startup configuration:
ver 08.0.95aT213
stack unit 1
  module 1 icx7150-48p-poe-port-management-module
  module 2 icx7150-2-copper-port-2g-module
  module 3 icx7150-4-sfp-plus-port-40g-module
  stack-port 1/3/1
  stack-port 1/3/3

vlan 4 name DATA by port
 untagged ethe 1/1/1 to 1/1/30
 router-interface ve 4

ip dhcp-server enable
ip dhcp-server pool test
 lease 1 0 0
 option  6 ip
 option  15 ascii
 option  44 ip

interface ve 4
 ip address

Hi Claude,

Pls start a new thread for the dhcp discussion since we are using this for DOM feature.

You may also open a support case for one of us to review and debug remote.



dear Jijo,

Regarding the DOM issue, can you see the added value in being able to monitor the DOM parameters while the link is down? in the field its extremely useful. I've relied on this feature (on other vendor's boxes) to, for example, instruct a remote tecnician to swap RX/TX pairs, or to check a single direction for a fiber cut. Also, in other cases it helped identified a not fully plugged in fiber as the received signal was there but was too low to enable link-up.

I am working with my regional customer engineer to see if we can open an RFE for this.


Dear Diego,

I understand the use case and it makes sense. We'll have to file an RFE to check the feasibility on the current architecture to take a final call. Pls let us know once the RFE# is filed.



RUCKUS Team Member

Hi Diego,

Regarding this new feature you are requesting, you can task  your systems Engineer to open a request for enhancement.

This will then be submitted to u=our PLM who will discuss the feasibility of  supporting it, the Engineering team will then review the hardware and software to see if it is feasible based on the limits, if possible they will add this new feature  but like is said you have to have signals going thru to be able to see the output of show optics.

Hope this helps.