Update Centos Linux 5.4 to Centos Linux 5.5

As you know, CentOS released version 5.5 and if you are using Centos Linux 5.4, you may actually upgrade it directly through your machine through the Internet with yum command.

To upgrade Centos version, you should take this 2 major steps.
1. Make a Backup.
2. Update package.

1. Make a backup
It is important to make a backup before you do any upgrade or installation. I will suggest you to have a full backup of your machine before doing the upgrade in case anything happen.

Make sure you have all of the data and database backup!

2. Update package
i) To upgrade your Centos, you may use yum command to upgrade it directly. However, you may try to check any update list available.
yum list updates

ii) You may update Centos as command below.
yum update

iii) Reboot your machine

iv) verify if everything working
uname -a
netstat -tulpn
tail -f /var/log/messages
cat /etc/redhat-release

Scheduled MySQL database backup

Assume that you are using crontab to schedule your task which you are using Unix system.

To schedule a database backup, it will be very easy as step below.

1. Log into your SSH.
2. Type “crontab -e” without quote.
3. Enter the command below.

0 0 * * * date=`date -I` ; mysqldump -a -u[user] -p[password]  [dbname] | gzip > /path/folder/[dbname]_$date.sql.gz

where you shall replace the user, password and dbname to your database information.

With the command as above it will actually backup your database by 12.00AM daily and place to the desired path and name with date.