WAN2 interface down , WAN2 interface is used for Internet breakout. With WAN2 [PPPoE] interface down internet breakout is not functional.

The output result of WAN2 interface of show dev command is as follows.

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wan2

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Type: pppoe

Forwarding: true

Mode: host

Admin Status: up

Operational Status: down

Provisional Status: up

Redundancy Status: non-redundant

Speed: 0 Mb/s

Duplex: unknown

in-octets: 1682

in-unicast-pkts: 23

in-errors: 0

out-octets: 0

out-unicast-pkts: 0

out-errors: 0

Error: 0

PPPoE State: 0

connection-status:ppp861 does not exist

failure: last-failure-time:XXXXX

last-failure-time:XXXXX

next-retry-time:XXXXX

pppd-exit-code:1

pppd-exit-reason:An immediate fatal error of some kind occurred, such as an essential system call failing, or running out of virtual memory.

Refer logs below

xxxx 128t-br2.local monitoring[834]: Command "/usr/sbin/ip netns exec pppoe-ns-1 /usr/sbin/ip addr show dev ppp19 up" failed: Device "ppp19" does not exist.
xxxx 128t-br2.local monitoring[843]: Command "/usr/sbin/ip netns exec pppoe-ns-1 /usr/sbin/ip addr show dev ppp19 up" failed: Device "ppp19" does not exist.
xxxx 128t-br2.local state[849]: Running command ['ip', 'netns', 'exec', 'pppoe-ns-1', 'ip', 'a', 'show', 'ppp19', 'up']
xxxx 128t-br2.local state[849]: Command "ip netns exec pppoe-ns-1 ip a show ppp19 up" failed: Device "ppp19" does not exist.
xxxx 128t-br2.local state[849]: Config file /var/lib/128technology/pppoe/ppp19.init does not exist, default config will be used
xxxx 128t-br2.local monitoring[892]: Command "/usr/sbin/ip netns exec pppoe-ns-1 /usr/sbin/ip addr show dev ppp19 up" failed: Device "ppp19" does not exist.
xxxx 128t-br2.local monitoring[901]: Command "/usr/sbin/ip netns exec pppoe-ns-1 /usr/sbin/ip addr show dev ppp19 up" failed: Device "ppp19" does not exist.

SSR is not receiving the required PPPoE PDU's. The issue is not on the SSR side, but on the PPPoE Server.