systemd-coredump - Invalid argument

Question

I'm trying to force a core dump using systemd-coredump, however, when I check my journal I see the following error:

[email protected]: Failed at step NETWORK spawning /lib/systemd/systemd-coredump: Invalid argument

and coredumpctl reports no cores.

My core_pattern is:

|/lib/systemd/systemd-coredump %P %u %g %s %t %c %e

/lib/systemd/systemd-coredump does exist and is executable. I have noticed that in the /etc/systemd/coredump.conf, everything is commented out.

[Coredump]
#Storage=external
#Compress=yes
#ProcessSizeMax=2G
#ExternalSizeMax=2G
#JournalSizeMax=767M
#MaxUse=
#KeepFree=

...which strikes me as odd...

Is there a way of "previewing" the arguments from core_pattern having been expanded that are fed into systemd-coredump - that way I could see if there is anything odd going on there... Otherwise, any idea what the problem could be?

Edit

I've also tried setting the core_pattern to point to a file like

bash -c 'echo "/home/root/core.%e.%p" > /proc/sys/kernel/core_pattern'

and

ulimit -c unlimited

But that doesn't work either - the core file doesn't get created.

Answer 1

I managed to get a core out of this (I think!) with a workaround. This still doesn't answer the question but at least gets me over this hump.

I created my own script:

#!/bin/bash 
echo $@ > /home/root/arguments.txt

if [ -p /dev/stdin ]; then
    echo "Data was piped to this script!" >> /home/root/arguments.txt
    cat > /home/root/core.bin 
else
    echo "No data received" >> /home/root/arguments.txt
fi

And set the core_pattern to pipe through this script rather than systemd-coredump

This allows me to both see the arguments passed into the script (so it does answer that part of the question!) contained in arguments.txt and the core itself is written to core.bin

(At least I think it's the core - it's not giving me a huge amount of info but I'm a bit of a newbie at gdb so that could be the reason.)