JUNOS Coredumps cheatsheet


A coredump captures the state of the process at the time it was terminated by the kernel. They can be generated automatically for a crash or programatically or based on a user request. Coredumps are very helpful in troubleshooting some kinds of problems like memory leaks. Below is a quick guide to different types of cores generated by JUNOS.

3 Types of Coredumps
JUNOS Kernel or RE
JUNOS daemons or processes. eg:RPD, Mib2d
PFE or FPC cores
Core storing locations
/var/crash
/var/tmp
use 'show system core-dumps' at CLI
How to Generate Coredumps
**Non of these cause Restarts or Reboots
Kernel live coredump: "request system live-core"
Daemon live core: request system core-dump running
From shell you use: gcore -s #process-id#
PFE: from pfe shell "write core". eg. FPC0 (vty)# write core