Session: Friday, November 8, 1:30pm – 2:15pm
Speaker: Shrikanth R Kamath, Juniper Networks
Abstract: Rescue Kernel and Direct Dumper was developed by Klara Systems for Juniper Networks to support direct dumping of kernel crash dumps onto the filesystem. This is useful for low end devices without the need for having a separate swap partition. The below notes are mostly from the man page written for the same.
The rescue kernel provides a flexible mechanism to save a kernel core dump following a panic. Traditionally, the approach used by FreeBSD has been to designate a “dump device,” typically the system’s swap partition, to which the kernel dumps memory after panicking and before rebooting. Following a reboot, the savecore(8) program recovers the saved memory dump and stores it in the filesystem. This approach has the downside of requiring a dedicated dump device, complicating system provisioning…