Hardware
- Switch: MikroTik CRS326-24S+2Q+RM
- QSFP+ 40Gbe transceivers: 2x of FS 40GBASE-LR4L QSFP+ 1310nm 2km LC Optical Transceiver Module for SMF
- Network card: Mellanox ConnectX-3 MCX353A-FCBT
- Connection is (Transceiver in switch) <--- Fiber ---> (Transceiver in network card, PC with Ubuntu 20.04)
Software
- RouterOS for MikroTik CRS326-24S+2Q+RM: v6.47.2
- SwOS: v2.12
- Network card firmware (latest available): 2.42.5000
Symptoms
- If I boot into RouterOS, the transceiver gets recognized without me doing anything, shows up as 40 Gbps connection, and works
- If I boot into SwOS, the transceiver gets recognized, but there is no link and does not work
What I tried in SwOS to fix the problem
- Turned off auto negotiation
- Set the port to 40 Gbe manually
None of that helped.
Any ideas?