CPU load increase sync_supers

[edwin.hsu]

I'm running a server that using cPanel on it Its like running for a year already, and there's no problem with it. I didn't change anything lately for the configuration for my server but yesterday just started a weird things appeared. My server CPU on Linode suddenly getting high, and I got a lot of emails said

*** SECURITY information for members.linode.com ***

<username>: user NOT in sudoers ; TTY=unknown ; PWD=/home/<username> ; USER=root ; COMMAND=cat /etc/passwd
<username>: user NOT in sudoers ; TTY=unknown ; PWD=/tmp ; USER=root ; COMMAND=/bin/killall -9 h h32 run yam yam32 yam64 minerd m64 xmrt.priv https .koworker tmp Smdp2 Umdp Umzp haha xiao

What should I do? I reboot my server and its back to normal yesterday, but it happened again this morning.

I also checked on my "top" history on my Linode, and I just got that [sync_supers] that makes the CPU high. I read some articles on this forum also and others sites that said need to killprocess and investigate the [sync_supers] using the PID, but since I already reboot the server, I cannot get the PID of this proccess, and I'm afraid they will come back again tonight.

Please help, I need your advice, what should I do to fix it?

Thank you very much

 

[rahulkshinde]

Hello @edwin.hsu,

Did you see as which user the sync_supers process was running ? is it root user or any other (including nobody), it must be root as sync_supers is a kernel thread and should not cause load.

If it was running with another user ownership then its surely a compromised. You should scan the user or even the server first.

 

[edwin.hsu]

Hello @edwin.hsu,

Did you see as which user the sync_supers process was running ? is it root user or any other (including nobody), it must be root as sync_supers is a kernel thread and should not cause load.

If it was running with another user ownership then its surely a compromised. You should scan the user or even the server first.

Hello @rahulkshinde,
I saw it was running by our own user(called unicorn) (not root and not nobody). But actually we didn't do anything on 2AM, or can be it was a cron tab? The weird things after the CPU getting high and I reboot my server is all my crontab list are gone.

Yesterday I just change our password and reduce the crontab list, only the important cron job, and today its fine, no CPU alert on 2AM anymore. But actually I'm still curious and afraid it will happened again

Thank you

 

[cPanelMichael]

Hello,

The following thread is a good place to start when troubleshooting high resource usage:

Troubleshooting high server loads on Linux servers

Thank you.

 

[rahulkshinde]

Hello @edwin.hsu

I think you should scan the files for the user unicorn and also check cronjobs for that user.

The thread mentioned by @cPanelMichael is also good start to check exactly what and why the load on server.