You can test the physical port by using a fiber loop from the transmit to receive on the optic then running some loopback tests per this document. If the test work then the local port in/out is working correctly and the issue is with the pair link communication in some fashion.
https://www.juniper.net/documentation/us/en/software/junos/interfaces-ethernet/topics/topic-map/ethernet-10-40-100-gigabit-loopback-testing.html#id-configure-a-static-address-resolution-protocol-table-entry------------------------------
Steve Puluka BSEET - Juniper Ambassador
IP Architect - DQE Communications Pittsburgh, PA (Metro Ethernet & ISP - Retired)
http://puluka.com/home------------------------------
Original Message:
Sent: 01-28-2023 07:09
From: fiber9
Subject: Troubelshoot Ex: Suddeny traffic is unidirectional from bidirectional
Hello,
No LAG or any bonding just 10G port.
No, the traffic is not delivered by another route.
It was working fine for a long time and suddenly it's unidirectional.
Tried shutting down another port to verify this but it's only one-way inbound.
Chassis hardware shows optics: Even replaced optics.
Interface diagnostics don't show any errors.
Is there any way to troubleshoot 10G module if its port has an issue or something?
Original Message:
Sent: 01-28-2023 06:39
From: Erik Slagter
Subject: Troubelshoot Ex: Suddeny traffic is unidirectional from bidirectional
Are we talking about a LAG here (bond, etherchannel, portchannel, whatever)?
Can it be the traffic is deliverd via another route (L2 or L3)?
Original Message:
Sent: 1/28/2023 2:22:00 AM
From: fiber9
Subject: Troubelshoot Ex: Suddeny traffic is unidirectional from bidirectional
Hello,
There is a weird issue with one of our switch 10G links. The traffic which was 1:1 bidirectional suddenly become unidirectional.
Traffic was around 3G In and out but now it is only inbound 3G. Tried to bounce the port but does not help.
In diagnostic it does not show any error for the port. Any idea what is the reason or how to troubleshoot if 10G module of Ex , optics or fiber issue?
Thanks