In the subscriber management environment, the RADIUS interim accounting records does not get populated with the subscriber statistics.

In subscriber management environment, RADIUS interim accounting records are not populated with the subscriber statistics after system reboot. During the boot up of the card, Nextgen stats module query the arp 
table to fetch the destination MAC addresses of the REs. This MAC addresses are used to push the interim stats to RE. The root cause of the issue is the arp entry has zero value for MAC address. In this case, the 
MAC of the routing engine is not learned by the nextgen-stats manager on the PFE. Use the following command to verify the problem.

"request pfe execute target fpc0 command "show nextgen-stats manager"
Nextgen Manager microcode stats:
==================================
Interim stats push from ASIC supported   : Yes
Is ucode running                         : Yes
configured values:
gen num                              : 17
interval slow                        : 300000 ms
interval fast                        : 60000 ms
callout period                       : 1 ms
vlan_re0                             : 0  
vlan_re1                             : 2
ip re0                               : 0x80000001
ip re1                               : 0x80000006
mac re0                              : 0x000000000000 <-----------not programmed
mac re1                              : 0x020100000005 <----------- programmed 
src ip                               : 0x8000001b
version                              : 0
member id                            : 0

Check out below external PR for more info:

https://prsearch.juniper.net/problemreport/PR1529602