Hi!
I just put some QSFP28 BiDi (JQ344A) transceivers in my 5945 switches (JQ074A, R6555). I get no link (Line protocol state: DOWN). Neither switch-to-switch nor switch-to-server works.
- The transceivers are supported on that HW and SW version.
- Transceiver diagnostics shows good signal on all 4 lanes.
- The switchports work ok, if I use DAC cables. Both switch-to-switch and switch-to-server.
- The transceivers are ok, I tested them in the server NICs (P25960-B21, connection from server to server).
I suspect some kind of issue with the autonegotiation. The manual however says, that a connection between HGE ports of two JQ074A should work with default settings.
Anyone can tell me what I'm missing?