On Junos MX with MPC10/11 and MX304 chip based platforms, when configured with 16k subscribers ( PPPoE { Point-to-Point Protocol} or DHCP { Dynamic Host Configuration Protocol } ) and COS ( Class of Service) settings, a crash in the Flexible PIC Concentrators (FPC) occurs during subscriber login and logout. Due to the crash the affected subscriber connection will be disconnected and re-establishing is not possible.

This issue can be seen for any type of subscriber scenario(pppoe or dhcp), the core-dumps will be seen in 16k subscribers with CoS configuration and Login/Logout the subscriber can trigger this, which leads the Broadband Edge Subscriber Management daemon (bbe-smgd) to get stuck eventually resulting the FPC crash.

To check the crash files, execute the CLI command:

user@device> show system core-dumps
-rw-r--r-- 1 root wheel 83901131 Dec 14 04:22 /var/crash/core-MX304-RE0-fpc0-aftd-trio.16883.2023_12_14.04_21_47.tgz
-rw-r--r-- 1 root wheel 672165672 Dec 18 08:11 /var/crash/core-MX304-RE1-fpc0-aftd-trio.16872.2023_12_18.08_09_05.tgz

This issue has been fixed in PR1782016.
https://prsearch.juniper.net/problemreport/PR1782016

Resolved-In:

evo:23.2R2-EVO evo:23.4R2-EVO evo:24.1R1-EVO junos:23.2R2 junos:23.4R2

https://prsearch.juniper.net/problemreport/PR1782016