sfp-ignore-rx-los doesn't stick (and what exactly does it do?)

RouterOS General
1

I use a hEX S with a GPON SFP (which has its own OS, IP address and management interface). When no fiber is connected, RouterOS doesn’t allow accessing the SFP’s web interface:

> /interface/ethernet/monitor sfp1
                        ;;; GPON SFP ONT
                      name: sfp1
                    status: no-link
          auto-negotiation: done
                 supported: 10M-baseT-half,10M-baseT-full,100M-baseT-half,100M-baseT-full,1G-baseT-half,1G-baseT-full
               advertising: 10M-baseT-half,10M-baseT-full,100M-baseT-half,100M-baseT-full,1G-baseT-half,1G-baseT-full
  link-partner-advertising: 10M-baseT-half,10M-baseT-full,100M-baseT-half
        sfp-module-present: yes
               sfp-rx-loss: yes
                  sfp-type: SFP/SFP+/SFP28/SFP56
        sfp-connector-type: SC
        sfp-link-length-sm: 20km
           sfp-vendor-name: ZYXEL
    sfp-vendor-part-number: PMG3000-D20B
       sfp-vendor-revision: V1.0
         sfp-vendor-serial: S[REDACTED]
    sfp-manufacturing-date: 15-05-25
            sfp-wavelength: 1310nm
           sfp-temperature: 52C
        sfp-supply-voltage: 3.3V
       sfp-tx-bias-current: 24mA
              sfp-tx-power: 3.01dBm

RouterOS 7.15 introduces the new setting sfp-ignore-rx-los. Is it supposed to fix this issue? I tried to enable it, but it doesn’t stick:

> /interface/ethernet/set sfp1 sfp-ignore-rx-los=yes
> /interface/ethernet/get sfp1 sfp-ignore-rx-los
>

Cheers
Maurice

2

With my experiments with ATT SFP module, I found that get command doesn’t work:

/interface/ethernet/get sfp-sfpplus1 sfp-ignore-rx-los

I found that only set and edit works, and works, as expected:

/interface/ethernet/set sfp-sfpplus1 sfp-ignore-rx-los=yes

/interface/ethernet/edit sfp-sfpplus1                   
value-name: sfp-ignore-rx-los

Looks like a bug.
I’m using RouterOS 7.16

3

It’s not bug, it’s how get works. Like this:

:put [ /interface/ethernet/get sfp-sfpplus1 sfp-ignore-rx-los ]
1 Like
4

Did anyone figure this out? I’m now on the latest Router OS 7.18 and the SFP option to ignore RX LOS doesn’t Save/Apply for me either. My interface is kept as default name: sfp1. No matter how many times I tried to APPLY/OK and refresh the page, the modification is ignored.

5

sfp-ignore-rx-los doesn’t work on the hEX S, support confirmed that to me a few months ago. They’re looking into it.

6

Thanks @mauricew. Can you please link me to that forum thread so I can follow this fix? I’ve been trying to work around this Hex S issue in Router OS terminal without success either. Am eager for the OS update with the bug fix.

7

I don’t think there’s a forum thread (other than this one). I reported a bug through the support portal.
If you want to contact support yourself, you can reference my ticket # SUP-162428.
Support responded in August 2024 and confirmed that they were able to replicate the issue. I haven’t heard back from them ever since.

8

Hi @MauriceW - confirming I’ve since submitted a new bug ticket for the Hex S (SUP-181536). In my ticket I referenced your previous support ticket ID from August 2024. Please advise if you hear anything on this and I will do the same. Perhaps Mikrotik devs will reply here for others encountering this.

9

@MauriceW it’s been a while. Do you know whether this feature has been implemented yet in any new firmware update?

10

Unfortunately not as of 7.20beta4. I still have an open ticket regarding this issue.