Juniper PTX5000 Hardware Manual page 541

CAUTION: After the OK LED lights steadily, wait at least 30 seconds before
removing the FPC again, removing an FPC from a different slot, or inserting an FPC
in a different slot.
You can also verify correct FPC and PIC functioning by issuing the show chassis fpc and show chassis fpc
pic-status commands, as described in
Figure 282: Connecting Fiber-Optic Cable to a PIC
"Maintaining the PTX5000 FPCs" on page 509.
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