After the following configuration change:
[edit chassis] + fpc 0 { + pic 0 { + port 13 { + speed 10g; + } + } + }
the LMIC0 went offline in MX304:
user@router-re0> show chassis pic fpc-slot 0 pic-slot 0 FPC slot 0, PIC slot 0 information: State Offline
The LMIC0 was brought back online after FPC reboot.
The issue has been fixed in the PR1685433. The issue is due to race condition in the interaction between the license daemon and chassis daemon.