IFRT: 'IFD media configuration' error log messages can be seen after a commit operation.

On MX router, following syslog messages can be seen after a configuration Commit operation:

Syslog Messages:
Mar 20 14:29:02.919 mx-re0 fpc1 PFEIFD: ifm link descrepancies from Ethernet (3) to Unspecified (0)
Mar 20 14:29:02.938 mx-re0 fpc1 IFRT: 'IFD configuration' (opcode 11) failed
Mar 20 14:29:02.952 mx-re0 fpc1  ifd 179; configuration error (7)

This issue is triggered by change interface type under FPC CPU utilization high condition(100%). 

For example, set FPC1 interface to ae group with FPC1 CPU 100%.

set interfaces xe-1/1/1:0 gigether-options 802.3ad ae0

When FPC CPU recovered to normal level, this error log won't happen again. 
This error log can be ignored safely.
But sometimes this error message always reports even no any configuration change.
Under this situation, reconfigure the problem interface can resolve this issue.

Mar 20 14:29:02.952 mx-re0 fpc1  ifd 179; configuration error (7)

In above error message, the interface index is 179.

So find this interface by below command:

> show interfaces | match "Physical interface|index: 179"
...
Physical interface: xe-1/1/1:0, Enabled, Physical link is Up <<<find the problem interface
 Interface index: 179, SNMP ifIndex: 785

user@mx# delete interfaces xe-1/1/1:0
[edit]
user@mx# commit
commit complete

[edit]
user@mx# rollback 1
load complete
[edit]
user@mx# commit
commit complete