kdump gets stuck during copying of /proc/vmcore

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Environment

SUSE Linux Enterprise Server 10 Service Pack 2

Situation

The target is to get a memory dump either automatically after a system crash/exception, or by triggering it with echo c > /proc/sysrq-trigger.
After the kdump kernel has been loaded, the last messages seen on the screen, before the kdump kernel hangs, looks like the following:

.....
waiting for devices /dev/sde1 to appear: ok
rootfs: major=8 minor=3 devn=2051
ok, dumping to /dev/sde1
-

After the above lines, there is no more activities.

Obviously, the copy process cp /proc/vmcore /dev/sde1 did not succeed.

NB: Here it is assumed that /dev/sde1 is the KDUMP_DUMPDEVICE.

Resolution

To solve this problem, edit /etc/sysconfig/kdump and do the following:

1) set the following values under /etc/sysconfig/dump

# /etc/sysconfig/kdump
KDUMP_KERNELVER="kdump"
KDUMP_COMMANDLINE=""
KEXEC_OPTIONS=" --args-linux "
KDUMP_RUNLEVEL="1"
KDUMP_IMMEDIATE_REBOOT="yes"
KDUMP_TRANSFER=""
KDUMP_SAVEDIR="/var/log/dump"
KDUMP_KEEP_OLD_DUMPS=5
KDUMP_FREE_DISK_SIZE=64
KDUMP_COMMANDLINE_APPEND=""
KDUMP_DUMPDEV="/dev/sde1" #---------> /dev/sde1 is just an example, please change it.
KDUMP_VERBOSE=3
KDUMP_DUMPLEVEL=31
KDUMP_DUMPFORMAT="compressed"

KDUMP_DUMPLEVEL=31 (or KDUMP_DUMPLEVEL=0x31) does strip all information that is not needed for the analysis. KDUMP_DUMPFORMAT is used to reduce the size of the dump.

2) Install makedumpfile package if it is not already installed. This package is needed whenever a KDUMP_DUMPLEVEL different from 0 is set.

Disclaimer

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