One additional thing I noticed, after interface description is assigned, the interface is removed from LLDP local information output.
Steps to reproduce:
1. I deleted previous interface description on interface. LLDP works and interface appears in LLDP local information
root@juniper-virtual-chassis-QFX5100# show | display set | match 0/0/23:1
{master:0}[edit]
Interface is visible in the lldp local info:
root@juniper-virtual-chassis-QFX5100# run show lldp local-information | match 0/0/23:1
xe-0/0/23:1 - 519 test999 Up << previous description that was deleted. Description is advertised in LLDP an visible on the remote device
{master:0}[edit]
2. I add a new description to the interface
root@juniper-virtual-chassis-QFX5100# set interfaces xe-0/0/23:1 description new_test888
{master:0}[edit]
root@juniper-virtual-chassis-QFX5100# commit
fpc0:
configuration check succeeds
fpc1:
commit complete
fpc0:
commit complete
Interface dissappears from lldp local-information
{master:0}[edit]
root@juniper-virtual-chassis-QFX5100# run show lldp local-information | match 0/0/23:1
{master:0}[edit]
LLDP is no longer working:
root@juniper-virtual-chassis-QFX5100# run show lldp neighbors interface xe-0/0/23:1
{master:0}[edit]
even if LLDP is activated on all interfaces:
run show lldp detail
LLDP : Enabled
Advertisement interval : 30 seconds
Transmit delay : 2 seconds
Hold timer : 120 seconds
Notification interval : 5 Second(s)
Config Trap Interval : 0 seconds
Connection Hold timer : 300 seconds
LLDP MED : Enabled
MED fast start count : 3 Packets
Port ID TLV subtype : interface-name
Port Description TLV type : interface-alias (ifAlias)
Interface Parent Interface LLDP LLDP-MED Power Negotiation Neighbor count
all - Enabled Enabled Enabled 7 <<<<
I try to activate LLDP on that specific interface also:
root@juniper-virtual-chassis-QFX5100# set protocols lldp interface xe-0/0/23:1
{master:0}[edit]
root@juniper-virtual-chassis-QFX5100# commit
fpc0:
configuration check succeeds
fpc1:
commit complete
fpc0:
commit complete
{master:0}[edit]
root@juniper-virtual-chassis-QFX5100# run show lldp detail
LLDP : Enabled
Advertisement interval : 30 seconds
Transmit delay : 2 seconds
Hold timer : 120 seconds
Notification interval : 5 Second(s)
Config Trap Interval : 0 seconds
Connection Hold timer : 300 seconds
LLDP MED : Enabled
MED fast start count : 3 Packets
Port ID TLV subtype : interface-name
Port Description TLV type : interface-alias (ifAlias)
Interface Parent Interface LLDP LLDP-MED Power Negotiation Neighbor count
all - Enabled Enabled Enabled 7 <<< no update here
3. I delete interface description
root@juniper-virtual-chassis-QFX5100# delete interfaces xe-0/0/23:1 description
{master:0}[edit]
root@juniper-virtual-chassis-QFX5100# commit
fpc0:
configuration check succeeds
fpc1:
commit complete
fpc0:
commit complete
{master:0}[edit]
root@juniper-virtual-chassis-QFX5100# run show lldp local-information | match 0/0/23:1
xe-0/0/23:1 - 519 new_test888 Up <<<
root@juniper-virtual-chassis-QFX5100# run show lldp detail
LLDP : Enabled
Advertisement interval : 30 seconds
Transmit delay : 2 seconds
Hold timer : 120 seconds
Notification interval : 5 Second(s)
Config Trap Interval : 0 seconds
Connection Hold timer : 300 seconds
LLDP MED : Enabled
MED fast start count : 3 Packets
Port ID TLV subtype : interface-name
Port Description TLV type : interface-alias (ifAlias)
Interface Parent Interface LLDP LLDP-MED Power Negotiation Neighbor count
all - Enabled Enabled Enabled 8
xe-0/0/23:1 - Enabled - Enabled 1 <<<
------------------------------
Andrei Tomus
------------------------------
Original Message:
Sent: 09-01-2023 15:19
From: Chuck Anderson
Subject: LLDP not working when interface has ONLY interface description configured
What does this show before and after adding the interface description?
show configuration | display inheritance | display set | match xe-0/0/23:1
------------------------------
Chuck Anderson
Original Message:
Sent: 09-01-2023 12:44
From: Andrei Tomus
Subject: LLDP not working when interface has ONLY interface description configured
I enabled LLDP logging on that interface:
Sep 1 16:35:58.208503 intf Inside lldp_handle_ifl_event for ge-0/0/2.16386 ifl event 4
Sep 1 16:35:58.208516 intf Inside lldp_handle_ifl_delete for ge-0/0/2.16386 ifl delete
Sep 1 16:35:58.208522 config ifl (ge-0/0/2.16386) proto: 1
Sep 1 16:35:58.208528 config Disabling ge-0/0/2.16386 fsm on ifl(lldp) for proto 1
Sep 1 16:35:58.208531 config DCBX delete interface: ge-0/0/2.16386
Sep 1 16:35:58.208535 config Proto 1 LLDP, no deletion of PPM state when LLDP-MED configuration is present
Sep 1 16:35:58.208538 config ifl (ge-0/0/2.16386) proto: 4
Sep 1 16:35:58.208542 config Disabling ge-0/0/2.16386 fsm on ifl(lldp) for proto 4
Sep 1 16:35:58.208549 config Proto 4, no deletion of PPM state when LLDPconfiguration is present
Sep 1 16:35:58.208553 rtsock Delete context 1 for ifl ge-0/0/2.16386
Sep 1 16:35:58.208557 intf Inside lldp_handle_ifd_delete, Send request to detach LLDP filters for intf ge-0/0/2
Sep 1 16:35:58.209367 proto Delete rdb . cleaning up dcbx sm
Sep 1 16:35:58.209397 proto tlv event is 2
Sep 1 16:35:58.209419 proto lldp_delete_rdb: The deleted rdb record's ifl =ge-0/0/2.16386,msap_id=\x04\x0w'\x14▒
Sep 1 16:35:58.209923 proto TTL expiry for RDB neighbor count on ifl(ge-0/0/2.16386) = 0
Sep 1 16:35:58.209934 rtsock deleting ifl ge-0/0/2.16386 iflidx 343
Sep 1 16:35:58.209938 config Deleting ifl ge-0/0/2.16386
Sep 1 16:35:58.209951 proto Deleted all vmembers from ifl ge-0/0/2.16386
Sep 1 16:35:58.209957 jvision lldp_telemetry_handle_intf_change: interface ge-0/0/2 delete event
Those delete operations seem strange for a simple fact like adding a description on the interface
------------------------------
Andrei Tomus
Original Message:
Sent: 08-31-2023 06:34
From: Andrei Tomus
Subject: LLDP not working when interface has ONLY interface description configured
Tested with:
Model: qfx5100-24q-2p
Junos: 20.2R3-S2.5
If the interface has no configuration (default state), and I only add interface description:
root@juniper-virtual-chassis-QFX5100# show | display set | match 0/0/23:1
set interfaces xe-0/0/23:1 description test
LLDP is not working
{master:0}[edit]
root@juniper-virtual-chassis-QFX5100# run show lldp neighbors interface xe-0/0/23:1
I did also packet captures, and apparently switch does not send LLDP. Also, it does not process received LLDP.
After I delete the interface description, LLDP works normally.
This behaviour does not seem correct, looks like a bug
------------------------------
Andrei Tomus
------------------------------