Problem
Kill a running process that is blocking another one from executing
tl;dr
List running processes
ps
Kill offending process where 12345 is the PID of the offending process
kill -9 12345
Solution
Sometimes you may see an error message, such as:
[root@ess001010]# yum install httpd -y
Loaded plugins: fastestmirror, security
Existing lock /var/run/yum.pid: another copy is running as pid 21544.
Another app is currently holding the yum lock; waiting for it to exit...
The other application is: yum
This happens when a process has been started, in this case yum, but it has not been shut down properly. To see currently running processes on Linux (any version), type:
ps
You will see a screen such as this one:
[root@ess001010]# ps
PID TTY TIME CMD
9098 pts/0 00:00:00 bash
21544 pts/0 00:00:00 yum
21597 pts/0 00:00:00 yum
21644 pts/0 00:00:00 ps
What you need to do is kill the pesky "yum" processes residing in your memory. To do that, type in:
kill -9 21544
Where 21544 is the PID (process ID). You can find PID in the left-most column of running processes. In this case, it's 21544.
- Updated