I have two CRS326-24G-2S+RM running RouterOS v6.43.4 using Generic FS.COM 1Gb FSP ( FS P/N: CWDM-SFP1G-ZX ) . When there is no link (fiber not plugged in) the switch sees the SFP and all the SFP info is there. There is nothing connected to the switches other than each other and me at one end (tried both ends) with a laptop. The switches have been configured with different IP addresses. As soon as the fiber is plugged in and the SFP link light comes on I can no longer access either switch.
Same setup using the same CRS326-24G-2S-RM at one end and CSS326-24G-2S-RM v2.8 at the other end. As soon as the CRS shows link it can no longer be accessed while at the same time the CSS can be accessed, sees the SFP and correctly shows the SFP info, but it does not show a link either via lights or the interface and can not reach the CRS.
Same setup using CSS and CSS neither ever show a link nor to they appear to have one.
Same setup forcing 1Gb FD on both ends. CRS results unchanged, shows link but can no longer access switch. The CSS is unchanged other than the link light / interface both show it has link even when no fiber is plugged into the SFP.
When I go to the update tab on the CSS it shows it is running 2.8, the most current available is 2.8 yet says there is an update available. When I tell it to download the upgrade/reboot it appears to do so but nothing has changed when it reboots. It still says it is on 2.8 and that there is an update available. The on that same tab reference a v2.9 and says "Make 1Gb SFPs work" . So... yeah I can't find any 2.9 but ... what is going on ?