Please sent your findings to email@example.com so they can look at a solution for this problem.I've done dozens of tests so far. Following steps:
- downgrading packages to 6.42.5
- downgrading firmware to 6.42.5
- remove power, wait 10s
- restore power and let the router boot with inserted SFP module (this seems to be important)
can quite reliably make sfp1 work again. Also it seems that first cold boot after firmware upgrade/downgrade without inserted SFP module starts this "permanent no-link problem" and the problem does not disappear by rebooting/powercycling; the only recovery, I was successful with, is performing the steps above.
In addition, when SFP module is inserted/removed to/from running router, copper ports lose link for approximately 4 seconds (link down/up events can be seen in router's log as well). Maybe this is due to CPU-to-switch lane reconfiguration (according to block diagram), please can someone from MikroTik confirm this?
<speculation>Can the problem with permanent no-link on sfp1 be related to lane configuration in early stages of ROS boot or even firmware initialization?</speculation>
Nevertheless, I cannot put device behaving this way into the production
Not according to the schemaDo you have an Ethernet cable connected to the port closest to the SFP?
If I am not wrong, this is a shared port, and you can only use one of them.
@madox : can you look up what's your S/N on this new routerboard that works is?After cold reboot (power off, power on) occasionally SFP doesn't get link up.
SFP diagnostic works normal, even values shown are the same as when it has link.
I tested SingleMode (1550/1310 nm) SFP brands: Optokon, GigaLight and 2 other Cisco compatible, I read on czech forum Maxlink SFP has the same problem (and someone wrote that even Mikrotik SFP doesn't work reliably). Those SFP work without problem on all our other devices, even on other Routerboards (RB2011) it works fine.
Devices on the other side: Edge-Core switches (ECS4120-28T, ECS4210-28T), Routeboards (RB760iGS, RB960PGS).
It happens 1-4 times out of 10, I couldn't find any relation.
Only cold reboot(s) helps, warm reboot (/system reboot) doesn't help (also warm reboot doesn't cause such problem).
I tried turning autonegotiation off and setting speed to 1Gbit on both sides - that didn't help.
It happens both on stable (6.42.7) and RC (6.43rc66) SW versions.
Nothing Mikrotik support suggested helped:
* disabling the interface on both ends
* setting the /system routerboard settings set boot-delay value (higher/lower than 2s)
And their conclusion "It seems to be a compatibility issue, we will try to improve it in the future, but for now it seems they are not compatible with our devices." doesn't help much.
If anyone found SFP that 100% work, please share. I have yet to (purchase and) test S-3553LC20D.
We are trying to replicate this issue with our own modules, but we are unable to observe such linking issues in our labs.
Did you try also with auto negotiate off and speed set to 1Gb/s?I have same problem.
I broght two HEX S devices, one is working withount any problems. On another SFP port is showing "no link".