TL;DR: Couln’t get the
netconsole kernel module to effectivelly send logs to my other computer -_- – EDIT: Turns out it was my graphics card (!) o_O` which btw. was also causing some strange failed SATA commands sent to one of my hard-disk – no more system hangs, and the good thing is I didn’t loose a costly hard-disk ;-.
Story: -_- Some strange crash problem occured today where my screen would
go blank early on during boot – did reboot in recovery mode and investigated
journalctl -b1 revealed a few big kernel Oops with long stacktraces,
but I couldn’t infer if and which module (if any) was causing it.
Hence I spent some time fiddling around, trying to get
netconsole to work, and
ultimately quit (for I had plans early this morning upon wakeup, to code or whatever).
It turned out that the problem disappear(s/ed) when I boot with the new Grub menu entry below, maybe this is just chance (or bad luck for non-reproducibility of things).
Had to generate another initrd image for the Arch-provided one didn’t have
netconsole.ko kernel module in it :
# vim /etc/mkinitcpio.conf MODULES="configfs atl1c netconsole" # mkinitcpio -g /boot/initramfs-linux-fabic.img
/boot/grub/grub.cfg and duplicated one of the entries there
(note that grub.cfg should not be edited by hand for it may be regenerated) :
linux /boot/vmlinuz-linux \ root=UUID=09022016-0924-1909-2411-2709cade0da3 rw \ resume=UUID=b09ea959-d8f7-400c-a829-91445640746c \ debug pause_on_oops=3 earlymodules=configfs,atl1c,netconsole break \ email@example.com/eth0,firstname.lastname@example.org/e8:9d:87:53:61:24 \ initrd /boot/initramfs-linux-fabic.img
debugwill have the kernel not filter its messages (ignoring
pause_on_oops=3is supposed to have the kernel pause upon emitting a Oops so that one may read something.
breakhave the initrd drop us with a BusyBox shell (ArchLinux only?).
netconsole=...is supposed to configure the corresponding module.
Also tried to configure this module from the BusyBox shell that
me with :
# modprobe netconsole \ email@example.com/enp4s0,firstname.lastname@example.org/e8:9d:87:53:61:24
On the other, target machine :
$ netcat -u -l -p 7777
But nothing was received, briefly checked my recent iptables rules, seemed okay.