This article provides information on how to halt the line cards with a dual RE on EX8200.
When EX8200 is required to be halted, due to some reasons, there are several different ways to do so, as per the version.
Previous version of 10.0R4:
> request chassis fpc offline slot <slot-num>
> request system halt both-routing-engines
From version 10.0R4 to 10.4R2 (with GRES disabled):
> request system halt both-routing-engines power-off fpc
From version 10.0R4 to 10.4R2 (with GRES enabled)
# deactivate chassis redundancy graceful-switchover
From version 10.4R3 and later: