Difference between revisions of "Vserver administration"
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m (→Errors) |
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| − | ==Errors== |
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| − | In some situations my CPU was burning like hell for days. |
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| − | <br>This was the vcontext/login process when using the command "vserver XX enter". |
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| − | <br>If it happens that the process is disconnected from its terminal it eats all the CPU :-( |
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| − | <br>I could reproduce the problem as follow: |
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| − | * ssh to the server as normal user |
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| − | * sudo su - |
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| − | * vserver XX enter |
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| − | * from another term, kill -9 one of the 2 su processes ("su -" or "-su") |
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| − | * quit the current terminal |
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| − | Now from another terminal you can see that |
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| − | vps ax|grep " login" |
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| − | shows a "login" process not attached to any tty (cf the "?") and using top you see it's running 100% cpu. |
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| − | Actually nature of this process is a bit strange because the real process is called vcontext as seen by top, pgrep and as you can see in /proc/XXX/status but its command line was overwritten with "login\0\0\0\0\0\0\0\0\0\0\0..." and commands like vps or pgrep -f show you this name "login" as you can see in /proc/XXX/cmdline. |
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| − | |||
| − | So I wrote a script and installed it in a cron to kill any such dandling process: |
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| − | <pre> |
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| − | pids=$(/usr/sbin/vps axc|\ |
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| − | egrep ' ? +[RS] +[1-9][0-9]*:[0-9]+ +vcontext'|\ |
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| − | sed 's/^ *\([0-9]\+\) .*$/\1/') |
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| − | [ "$pids" != "" ] && \ |
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| − | echo "Killing dandling login" && \ |
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| − | kill $pids |
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| − | </pre> |
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| − | And /etc/cron.d/watch-vcontext: |
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| − | <pre> |
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| − | MAILTO=root |
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| − | */5 * * * * root /home/vservers/tools/kill-vcontext |
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| − | </pre> |
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| − | This also shows something weird: processes in vservers don't appear with ps ax, ok, they appear with vps ax. |
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| − | <br>Now if I want to kill one of them from the host: |
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| − | vkill 29825 |
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| − | vkill: vc_ctx_kill(): No such process |
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| − | chcontext --ctx 1 kill 29825 |
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| − | <no error but nothing happen neither> |
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| − | kill 29825 |
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| − | <works!!> |
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===GrSec=== |
===GrSec=== |
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* http://people.linux-vserver.org/~harry/_README_ |
* http://people.linux-vserver.org/~harry/_README_ |
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