A Juniper Transceiver may show up as unsupported sometimes

Sometimes, a Juniper Transceiver may show up as unsupported. This article outlines the error and troubleshooting steps to address it. This could be due to a transient or a permanent hardware issue with either SFP/PIC/FPC. The issue maybe encountered due to initialization failures.

Here is a snippet of the logs from the lab device during issue period for reference:

labroot@mx480-lab> show chassis hardware 
Hardware inventory:
Item       Version Part number Serial number   Description
Chassis                        JN12774DBAFB    MX480
FPC 5       REV33  750-063184  EABZ46xx     MPC2E NG PQ & Flex Q
 MIC 1     REV26  750-049846  EABX77xx     3D 20x 1GE(LAN)-E,SFP
   PIC 3         BUILTIN   BUILTIN      10x1GE(LAN) -E SFP
               Xcvr 6   REV01  740-031851  N8SA2XX      SFP-SX
 
labroot@mx480-lab> show chassis pic fpc-slot 5 pic-slot 3 
FPC slot 5, PIC slot 3 information:
 Type        10x1GE(LAN) -E SFP
 State       Online  
 PIC version     1.26
 Uptime       54 days,20 hours, 45 minutes, 16 seconds
PIC port information:
                   Fiber     Xcvr vendor  Wave- Xcvr   JNPR
 Port Cable type  type Xcvr vendor  part number  length Firmware  Rev
 5 GIGE 1000SX  MM FINISARCORP.  FTLF8519P3BNL-J3 850 nm 0.0   REV 01
 6 UNKNOWN CABLE  n/a          n/a  0.0    
 

In the below logs we see that the FPC is reporting I2c errors and MIC is unable to read SFP EEPROM on port 5/3/6:

Nov 16 00:12:34 mx480-lab : %PFE-5: fpc5 MIC(5/3)(6): SFP unplugged

Nov 16 00:14:28 mx480-lab : %PFE-5: fpc5 MIC(5/3)(6): SFPplugged in

Nov 16 00:14:29 mx480-lab : %PFE-5: fpc5 MIC_SFP_MUX_RESET: mic_sfp_pca9548_swtbl_clean: MIC(5/3) Reset MUX to SFP ports

Nov 16 00:14:29 mx480-lab : %PFE-5: fpc5 Reset media mux for mic slot 1

Nov 16 00:14:29 mx480-lab : %PFE-3: fpc5 MIC(5/3)(6), SFP 17: in sfp_read_range, failed to read SFP EEPROM address 0

Nov 16 00:14:29 mx480-lab : %PFE-3: fpc5 mpcs_i2c_single_io: MPCS(0) ctlr 0 group 1 addr 0x50 prio 0 flags 0x0 failed status 0x1

Nov 16 00:14:29 mx480-lab : %PFE-3: fpc5 I2C Failed device: group 0x41 address 0x50

Nov 16 00:14:29 mx480-lab : %PFE-3: fpc5 mpcs_i2c_single_io: MPCS(0) ctlr 0 group 1 addr 0x50 prio 0 flags 0x0 failed status 0x1

Nov 16 00:14:30 mx480-lab : %PFE-3: fpc5 MIC(5/3)(6), SFP 17:unknown OC3 optic type 0

Once it is confirmed that the SFP used is Juniper SFP, we need to isolate the problem to the PIC/SFP/FPC. 

Perform the following troubleshooting shoot steps during MW: 

1. Swap sfp on port 5/3/6 with another working SFP.

Collect show chassis hardware and check the status of the SFPs.

Confirm if the unsupported output is still shown on port 5/3/6 or if it followed the SFP. 

2. If the working SFP is showing the same unsupported output on port 5/3/6, please reboot MIC1: 

request chassis mic offline fpc-slot <FPC#> mic-slot <MIC#>

request chassis mic online fpc-slot <FPC#> mic-slot <MIC#>

Once rebooted, please collect show chassis hardware again.

3. If the issue remains after the reboot, contact JTAC support as MIC1 replacement may be needed

NA