Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Questions tagged [kdump]

20 questions
4
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0 answers

Hard lockup triggers reboot but no panic and no kdump

I have been trying to debug random system freezes when running the 4.14.93-rt kernel. To this end, I have enabled the lockup detector in the kernel using the following…
tomptz
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3
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1 answer

How to reset the video mode of the Intel driver i915 for the kexec-ed kernel so I can see what kexec kernel is doing?

I'm running Arch Linux and I've set up kdump so that when the current kernel panics(or I manually induce a crash via sysrq+c) then another kernel(the kexec kernel) starts up in order to create a crash dump so that I can later inspect it. The problem…
user353741
2
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0 answers

kdump.service failed to start on CentOS 8

Issue kdump.service fails to start on CentOS 8 virtual machine on Google Cloud. Restarting the service keeps reproducing the same error. It seems the secure boot is causing the issue or is at least related to it. Required key cannot be loaded. The…
Skyler
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2
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3 answers

kdump in CentOS 7

I wanted to migrate to CentOS 7.5 from CentOS 6.9. during installation I saw an option kdump that i could enable or disable. I wonder what is kdump and disabling it has any bad effect on server? I want to install database on my server later I just…
BlackCrystal
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1
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1 answer

Unable to Get Kernel Crash Dump on Kernel Panic

I'm using kexec-tools to get a crash dump of kernel on kernel panic. However, when I trigger the panic using sysrq-trigger, the system freezes. I have to power off and then power on to restore the system. There is no automatic reboot and no crash…
Harsh
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1
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Is UN state and D state in Linux processes are same?

I want to understand is the UN and D process state is the same? During the analysis of vmcore (crash dump) I have found lots of UN state processes. And when I googled it I hardly found any document on the UN state but found D state document. Can…
Ashish
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Why is crash command exiting without prompt?

I've installed a debug kernel and enabled kdump. The coredump was generated successfully, but when I try to load the vmcore after reboot, crash command just quit without prompt: # crash…
daisy
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Not able to save crash dump using kdump

I have a VPS server on amazon's AWS Lightsail service. I've been testing kdump using the following two commands(to trigger an automatic kernel crash): # echo 1 > /proc/sys/kernel/sysrq # echo c > /proc/sysrq-trigger The problem is that the system…
xczzhh
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1
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Kernel crashes at different points

I have made a custom board using Tegra TK1 ARM processor. I have compiled uboot and kernel for it and flashed into it. Now when it starts booting, sometimes it boots successfully while sometimes kernel crashes. Everytime it crashes at different…
faiz07
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1 answer

echo c > /proc/sysrq-trigger doesn't reboot the system

I am trying to collect a core dump in result of kernel panic. Installed and configured kdump, but when executing echo c > /proc/sysrq-trigger, everything just hangs and the reboot doesn't happen. I don't even get any output in the result of running…
Mr.SrJenea
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Crashkernel not starting after crash

I am trying to start a crash kernel using Linux's Kernel Crash Dump. Both of the host and crash kernel are compiled linux-4.13.16 kernel. Unfortunately, the crash kernel fails to start after the crash occurs. iomem reports reserved space for crash…
Proy
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Cannot get kernel crash dump saved and reboot

I need to get a crash dump of my linux kernel. I am going to describe the scenario: Hardware: Notebook Dell E5450. Linux Distribution: Linux Mint 18.3 (Ubuntu 16.04). SysRq: enabled by /etc/sysctl.d/10-magic-sysrq.conf. Installed packages:…
Antonio Petricca
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1
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1 answer

Could the capture kernel be used as a normal kernel after a kexec?

I have read about the kexec/kdump facilities, we know that crashed/panic'ed kernel is made available via /proc/vmcore. I have heard people use kexec based booting to bypass EFI/BIOS/FW initialization stages to speed up their OS patching activities…
Junaid Shahid
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0
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1 answer

kdump.conf - file contents remove after trigger crash

I have changed the path in kdump.conf from /var/crash to /home/crash/kdump. System is AlmaLinux 8. After triggering a crash with echo c > /proc/sysrq-trigger, the crash dump in still placed in the /var/crash folder. When I checked the kdump.conf…
supmethods
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How to start kdump service as early as possible

yocto LTS kdump have no early kdump feature let said if i want start kdump as earlier as possible how should i do that? i edit the service file to below [Unit] Description=Reboot and dump vmcore via…
KJ L
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