Kernel Crash Trace Log

[mitt]

I am trying to log the kernel logs when it crashes, however the configuration is not working for me.
I tried with netcat if the communication worked, and yes, I was able to connect to port 5555 by UDP.

Server 1

# cat /etc/default/grub

GRUB_DEFAULT=0
GRUB_TIMEOUT=5
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet netconsole=5555@152.128.0.4/eth0,5555@162.128.0.14/08:00:27:d4:f5:ae loglevel=7"
GRUB_CMDLINE_LINUX=""

--
Server 2

# screen nc -l -p 5555 -u

--
Server 1

# reboot

--

Server 2

root@test2:~# cat /var/log/netconsole/152.128.0.4.log
cat: /var/log/netconsole/152.128.0.4.log: No such file or directory

I do all the steps as explained in the guide but I can't get the file to be saved

 

[datschlatscher]

As far as I understand, you forgot to pipe the file somewhere in the nc command, e.g. screen nc -l -p 5555 -u > /var/log/netconsole/152.128.0.4.log

nc does not do this automatically. However, if you attach to the screen session you should be able to read the output that is received by Server 2.

It might be helpful to link the guide you are following, which might clear up some questions here.

 

[fiona]

Hi,
stupid question, but did you run update-grub after changing the grub configuration? You can check with cat /proc/cmdline to see what's currently being used.

 

[mitt]

As far as I understand, you forgot to pipe the file somewhere in the nc command, e.g. screen nc -l -p 5555 -u > /var/log/netconsole/152.128.0.4.log

nc does not do this automatically. However, if you attach to the screen session you should be able to read the output that is received by Server 2.

It might be helpful to link the guide you are following, which might clear up some questions here.

https://pve.proxmox.com/wiki/Kernel_Crash_Trace_Log

 

[mitt]

Hi,
stupid question, but did you run update-grub after changing the grub configuration? You can check with cat /proc/cmdline to see what's currently being used.

Yes

 

[mitt]

As far as I understand, you forgot to pipe the file somewhere in the nc command, e.g. screen nc -l -p 5555 -u > /var/log/netconsole/152.128.0.4.log

nc does not do this automatically. However, if you attach to the screen session you should be able to read the output that is received by Server 2.

It might be helpful to link the guide you are following, which might clear up some questions here.

I just tried adding the file path in netcat, however it doesn't print anything to the console either.
It doesn't save anything to the file.

 

[mitt]

now i was able to get it to print to the console but it doesn't save to file

 

[fiona]

now i was able to get it to print to the console but it doesn't save to file

What if you don't prefix the command with screen?