Description

When the QFX10008 is running the version 22.2R3-S2 is not capable to detect the directly connected neighbor on em0 management interface, other switches connected on "et" interfaces are detected properly via lldp.

Symptoms

-The incident has been reported after an upgrade from 21.2R2-S1 to 22.2R3-S2.
-The incident is not caused by the upgrade.
- When the QFX10008 is running the version 22.2R3-S2, is not able to detect the neighboring device connected on em0 interface
- The behavior has not been faced on other interfaces.
- The EX switch doesn't have the same issue in the same version.
 

Solution

The problem has been tested on versions 23.2R1 and 23.2R1-S1, and it has been confirmed that is resolved.
Topology
 QFX-em0----ge-0/0/10-EX4100-48t

Devices running the version 22.3R2-S2
QFX10008
root@QFX10008-NEIG> show version
Hostname: QFX10008-NEIG
Model: qfx10008
Junos: 22.2R3- S2.8
root@QFX10008-NEIG> show lldp neighbors
Local Interface  Parent Interface  Chassis Id     Port info     System Name
                                                                                 ========>>The output is empty
root@QFX10008-NEIG> 


EX4100
Hostname: EX4100-neigh
Model: ex4100-48t
Junos: 22.3R2-S2.9
root@EX4100-neigh> show lldp neighbors
Local Interface  Parent Interface  Chassis Id     Port info     System Name
ge-0/0/10               -                                            em0        QFX10008-NEIG. ==> The QFX is detected properly 


When upgrading the QFX10008 to versions like 23.2R1 and 22.3R2 -S2, the issue is resolved
QFX10008
root@QFX10008-NEIG> show version
Hostname: QFX10008-NEIG
Model: qfx10008
Junos: 23.2R1.14

root@QFX10008-NEIG> show lldp neighbors
Local Interface  Parent Interface  Chassis Id     Port info     System Name
em0                      -                                              ge-0/0/10     EX4100-neigh =>Neighbor detected properly


QFX10008
root@QFX10008-NEIG> show version
Hostname: QFX10008-NEIG
Model: qfx10008
Junos: 23.2R1 -S1

root@QFX10008-NEIG> show lldp neighbors
Local Interface  Parent Interface  Chassis Id     Port info     System Name
em0                      -                                              ge-0/0/10     EX4100-neigh =>Neighbor detected properly

After looking for related cases, found below Problem Report,
https://prsearch.juniper.net/problemreport/PR1763053

Customer applied workaround on the other end as mentioned over the PR and issue was fixed,
#set protocols lldp tlv-filter cloud-connect-event

Modification History

01/18/24- Moved to validated