5. Upgrade Oozie

Execute the following command on the Oozie server and client machines:
- For RHEL/CentOS:
```
yum upgrade oozie
            
```
- For SLES:
```
zypper update oozie
            
```
Start Oozie.
```
 sudo su -l oozie -c "cd $OOZIE_LOG_DIR/log; /usr/lib/oozie/bin/oozie-start.sh" 
```
where $OOZIE_LOG_DIR is the directory where Oozie log files are stored (for example: /var/log/oozie).

Validate Oozie.

oozie admin -oozie http://$fully.qualified.domain.name_for_Oozie_hostmachine:11000/oozie -status

You should see the following output:

System mode: NORMAL