Can you change the fab config to global config instead of groups? Never seen this config and not sure if its contributing for some reason
delete groups node0 interfaces fab0
delete groups node0 interfaces fab1
set interfaces fab0 fabric-options member-interfaces ge-0/0/0
set interfaces fab1 fabric-options member-interfaces ge-7/0/0
set interfaces fab0 fabric-options member-interfaces ge-0/0/0
set interfaces fab1 fabric-options member-interfaces ge-7/0/0
commit
Also , I am not sure if the traceoption is applied to troubleshoot this issue, if so, please add a packet filter to trace specific flow otherwise it will capture all traffic and result in high CPU usage.
set security flow traceoptions file dnat.log
set security flow traceoptions flag basic-datapath
Regarding interfaces in admin down state, it should not cause this issue.
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