I have a Juniper EX4200 with a EX-UM-2X4SFP uplink module, and it’s not recognizing the SFP module I’m trying to connect to Single Mode Fiber.

This is my hardware

run show chassis hardware

I can see the fiber card and module I have inserted

Hardware inventory:
Item             Version  Part number  Serial number     Description
Chassis                                BP0211100375      EX4200-48T
Routing Engine 0 REV 08   750-033063   BP0211100375      EX4200-48T, 8 POE
FPC 0            REV 08   750-033063   BP0211100375      EX4200-48T, 8 POE
  CPU                     BUILTIN      BUILTIN           FPC CPU
  PIC 0                   BUILTIN      BUILTIN           48x 10/100/1000 Base-T
  PIC 1          REV 05   711-026017   CH0211241152      2x 10GE SFP+
    Xcvr 1                NON-SFP+     PC71UN9           SFP-LX10
Power Supply 0   REV 04   740-020957   AT0511075037      PS 320W AC
Power Supply 1   REV 05   740-020957   AT0511121721      PS 320W AC
Fan Tray                                                 Fan Tray

But next, if I check the PIC module, it shows my fiber module

run show chassis pic fpc-slot 0 pic-slot 1

output

FPC slot 0, PIC slot 1 information:
  Type                             2x 10GE SFP+
  State                            Online    
  PIC version                  1.5
  Uptime			 124 days, 1 hour, 28 minutes, 57 seconds

PIC port information:
                          Fiber                    Xcvr vendor
  Port  Cable type        type  Xcvr vendor        part number       Wavelength
  1     GIGE 1000LX10     SM    FINISAR CORP.      FTRJ1319P1BTL     1310 nm 

Now if I try show interface status it doesn’t give me anything, it’s like the interface doesn’t really exist.

run show interfaces ge-0/1/1

result

error: device ge-0/1/1 not found

So, what is the problem?

This key is in the output above it’s in 2x 10G mode.  The default is not for connecting 4 1G fiber SFP, it’s two 10G SFP+ modules.  We need to set it to 4x 1G mode so we can use all 4 ports.

To change the mode to 4x 1G SFP modules you would use

set chassis fpc 0 pic 1 sfpplus pic-mode 1g

or to change it back to 2x 10G SFP+

set chassis fpc 0 pic 1 sfpplus pic-mode 10g

Documentation says, if you’re running Junos OS version earlier than 10.0 you’ll need to reboot, I’m running 12.x so it took a minute but changes became effect immediately.

You can check the module again

run show chassis pic fpc-slot 0 pic-slot 1

you’ll see it change from 2x 10GE SFP+ to 4x GE SFP+ in the Type.

FPC slot 0, PIC slot 1 information:
  Type                             4x GE SFP+
  State                            Online    
  PIC version                  1.5
  Uptime			 5 minutes, 29 seconds

Now if i run show interface like earlier.

run show interfaces ge-0/1/1

I get the output I expect

Physical interface: ge-0/1/1, Enabled, Physical link is Up
  Interface index: 177, SNMP ifIndex: 600
  Description: cust-xxxx-smf
  Link-level type: Ethernet, MTU: 1514, Speed: 1000mbps, Duplex: Full-Duplex,
  BPDU Error: None, MAC-REWRITE Error: None, Loopback: Disabled,
  Source filtering: Disabled, Flow control: Enabled, Auto-negotiation: Enabled,
  Remote fault: Online
  Device flags   : Present Running
  Interface flags: SNMP-Traps Internal: 0x0
  Link flags     : None
  CoS queues     : 8 supported, 8 maximum usable queues
  Current address: 5c:5e:ab:63:c6:34, Hardware address: 5c:5e:ab:63:c6:34
  Last flapped   : 2017-09-01 14:48:19 PDT (00:02:18 ago)
  Input rate     : 0 bps (0 pps)
  Output rate    : 0 bps (0 pps)
  Active alarms  : None
  Active defects : None
  Interface transmit statistics: Disabled

  Logical interface ge-0/1/1.0 (Index 115) (SNMP ifIndex 601) 
    Flags: SNMP-Traps 0x0 Encapsulation: ENET2
    Input packets : 96 
    Output packets: 106
    Protocol eth-switch                 
      Flags: None

You should be good now.