EX4400 interfaces remain down after replacing a SFP-T with SFP-SX

Description

EX4400 interfaces remain down after replacing a SFP-T with SFP-SX. The link mode setting failed while applying the auto-negotiation config. Hence link is not coming up. same issue can be see when replacing SFP-FX-PHY with SFP-SX

Symptoms

after replacing SFP-T with SFP-SX , interface remain down as shown below:

user@switch> show interfaces terse | match ge-0/0/20
ge-0/0/20 up up            <<<<<<< interface up with SFP-T
ge-0/0/20.16386 up up

user@switch> show chassis hardware
Hardware inventory:
Item Version Part number Serial number Description
Chassis YK4322410979 EX4400-48F
Pseudo CB 0
Routing Engine 0 BUILTIN BUILTIN RE-EX4400-48F
FPC 0 REV 11 650-114385 YK4322410979 EX4400-48F
CPU BUILTIN BUILTIN FPC CPU
PIC 0 REV 11 BUILTIN BUILTIN 36x 1G SFP, 12x 1G/10G SFP/SFP+
Xcvr 13 REV 01 740-011782 PBB1D15 SFP-SX
Xcvr 20 REV 02 740-013111 A331627 SFP-T        <<<<<<< when replace SFP-T with SFP-SX

user@switch> show interfaces terse | match ge-0/0/20
ge-0/0/20 up down        <<<<<<< interface down with SFP-SX
ge-0/0/20.16386 up down

Solution

PYH soft reset is needed once the spf get removed. this is fixed in Junos releases listed on PR1805370.
as workaround customer need to put the new SFP-SX and reboot the box

Modification History

2024-09-06 : Modified the solution section - Made KB public
2024-04-26 : Article Created

Related Information

https://gnats.juniper.net/web/default/1805370#summary_tab