Customer might see an issue wherein the LAG interface and the child interface might show Physically down.
This is usually seen due to the FEC and auto-negotiation mismatch on both the devices. The default FEC mode may vary between different types of devices.
Can be verified using the below command:
root@switch2# run show interfaces et-0/0/46 extensive |match fec
Active defects : None
Ethernet FEC Mode : NONE <<<<
FEC modes:
fec108
IEEE 802.3by Clause 108, Reed-Solomon FEC (RS-FEC) on 25g links
fec74
FEC74 enabled
fec91
IEEE 802.3bj Clause 91, Reed-Solomon FEC (RS-FEC)
none
FEC disabled
Issue resolved after configuring the below lines and then bouncing the ae interfaces during a MW.
#set interfaces ge-0/2/0 gigether-options no-auto-negotiation
#set interfaces ge-0/2/0 gigether-options fec none