how to debug random domU reboot

Cloudmin
1

Hi,

I just noticed one of my XEN domU’s rebooting by itself. No one was logged in and it wasn’t under load, but just rebooted. It rebooted again about an hour or 2 later

Is there any way to see why to see what caused this, either from domU, or dom0 ?

/var/log/messages has no indicative reason, but here it is:

Aug 1 18:47:06 venus shutdown[13758]: shutting down for system reboot
Aug 1 18:47:06 venus init: Switching to runlevel: 6
Aug 1 18:47:13 venus kernel: Kernel logging (proc) stopped.
Aug 1 18:47:13 venus kernel: Kernel log daemon terminating.
Aug 1 18:47:14 venus exiting on signal 15
Aug 1 18:47:49 venus syslogd 1.4.1: restart.
Aug 1 18:47:49 venus kernel: klogd 1.4.1, log source = /proc/kmsg started.
Aug 1 18:47:49 venus kernel: Bootdata ok (command line is console=xvc0 root=/d
ev/sda1 ro)
Aug 1 18:47:49 venus kernel: Linux version 2.6.18-164.2.1.el5xen (mockbuild@bui
lder10.centos.org) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-46)) #1 SMP Wed Se
p 30 13:27:58 EDT 2009
Aug 1 18:47:49 venus kernel: BIOS-provided physical RAM map:
Aug 1 18:47:49 venus kernel: Xen: 0000000000000000 - 0000000200c00000 (usable)
Aug 1 18:47:49 venus kernel: No mptable found.
Aug 1 18:47:49 venus kernel: Built 1 zonelists. Total pages: 2100224
Aug 1 18:47:49 venus kernel: Kernel command line: console=xvc0 root=/dev/sda1
ro
Aug 1 18:47:49 venus kernel: Initializing CPU#0
Aug 1 18:47:49 venus kernel: PID hash table entries: 4096 (order: 12, 32768 byt

And then the 2nd instance:

Aug 1 19:38:56 venus kernel: Firewall: TCP_IN Blocked IN=eth0 OUT= MAC=00:16:
3e:c2:d7:b2:00:0c:db:b8:90:00:08:00 SRC=190.209.57.198 DST=96.31.66.10 LEN=48 TO
S=0x00 PREC=0x00 TTL=121 ID=40899 DF PROTO=TCP SPT=3878 DPT=5900 WINDOW=65535 RE
S=0x00 SYN URGP=0
Aug 1 19:38:59 venus pure-ftpd: (?@127.0.0.1) [INFO] __cpanel__service__auth__f
tpd__7VQXuaR61sb40IvRgIa2H0sYxTDB1dprBBRF6ULv5oDmwkql6v_qsE4S4GDb1qMp is now log
ged in
Aug 1 19:38:59 venus pure-ftpd: (__cpanel__service__auth__ftpd__7VQXuaR61sb40Iv
RgIa2H0sYxTDB1dprBBRF6ULv5oDmwkql6v_qsE4S4GDb1qMp@127.0.0.1) [INFO] Logout.
Aug 1 19:41:57 venus shutdown[27225]: shutting down for system reboot
Aug 1 19:41:57 venus init: Switching to runlevel: 6
Aug 1 19:42:06 venus kernel: Kernel logging (proc) stopped.
Aug 1 19:42:06 venus kernel: Kernel log daemon terminating.
Aug 1 19:42:07 venus exiting on signal 15
Aug 1 19:42:39 venus syslogd 1.4.1: restart.
Aug 1 19:42:39 venus kernel: klogd 1.4.1, log source = /proc/kmsg started.
Aug 1 19:42:39 venus kernel: Bootdata ok (command line is console=xvc0 root=/d
ev/sda1 ro)
Aug 1 19:42:39 venus kernel: Linux version 2.6.18-164.2.1.el5xen (mockbuild@bui
lder10.centos.org) (gcc version 4.1.2 20080704 (Red Hat 4.1.2-46)) #1 SMP Wed Se
p 30 13:27:58 EDT 2009
Aug 1 19:42:39 venus kernel: BIOS-provided physical RAM map:
Aug 1 19:42:39 venus kernel: Xen: 0000000000000000 - 0000000200c00000 (usable)

How do I find out what caused this?

–
Kind Regards
Rudi Ahlers
SoftDux

Website: http://www.SoftDux.com
Technical Blog: http://Blog.SoftDux.com
Office: 087 805 9573
Cell: 082 554 7532

2

Can anyone help me with this please?

3

I’m not really sure what might cause a reboot such as that… do you have other Virtual Machines on that same server? Are you seeing the problem with them as well, or is it just this one?

-Eric

4

I had random reboots on a vps myself and couldn’t figure out what caused it. There were no indications at all.
In the end it was solved as the client cancelled his subscription.

5

It’s only this one VPS that reboots, the other VPS’s on the same server doesn’t.