Do You Need More Disk Space for the MySQL Server at Amazon Web Services (AWS/EC2)?

If you deal with large databases, you will probably need more than the provisioned storage of the default Amazon AMI (8GB).


UPDATE: Since in many cases you may need to swap between the current disk and a new larger one, I've added in green comments regarding this case.

The following 10 steps guide will help you expand your disk meet your business needs:

1. Create a new storage volume at the Amazon console (or using AWS API). Make sure it is big enough to accommodate storage, log files, bin files and future growth. Notice! verify the new drive is in the same availability zone as the target instance.
2. Write down the mount name you chosen. For example: /dev/sdf.
3. Mount the disk to your system according to Chris Dean post:
1. sudo mkfs.ext4 /dev/sdf where /dev/sdf is the mount name you chose.
4. Shutdown the MySQL daemon: sudo /etc/init.d/mysql stop
5. Unmount the current disk umount /dev/sdf
6. Move your current MySQL data directory to a temporary directory: sudo mv /var/lib/mysql  /var/lib/mysql.old or mount the previous disk to mysql.old by creating a new folder and changing the /etc/fstab as described bellow.
7. Recreate the MySQL data directory and provide the needed permissions:
1. sudo mkdir /var/lib/mysql
2. sudo chown mysql:mysql  /var/lib/mysql
8. Mount the new disk to the new directory:
1. Add another line to /etc/fstab (sudo vi /etc/fstab): /dev/sdf /var/lib/mysql ext4 defaults 1 2
2. Mount the disk: sudo mount /var/lib/mysql
3. Verify everything is Okay with df
9. Move the files from the temporary directory back to the new data directory sudo mv /var/lib/mysql.old/* /var/lib/mysql
10. Remove the old directory: sudo rmdir /var/lib/mysql.old and unmount the old disk umount /dev/sdf
11. Restart you MySQL: sudo /etc/init.d/mysql start

Note:
xfs today is the new kid in block w/ better performance w/ SSD disks and already stable.
Use the following commands if you choose it:
sudo apt-get install -y xfsprogs
sudo mkfs.xfs -f /dev/xvdf
vi /etc/fstab
/dev/xvdf /var/lib/mysql/ xfs defaults 0 2

Bottom Line

A combination of cloud knowledge, Linux sysadmin, MySQL expertise and careful work will help you go through the scale and growth challenges.

Keep Performing,

Moshe Kaplan

MySQL CentOS and Amazon Web Services (AWS)

Many Linux experts prefer CentOS. The reason is clear, Redhat's RHEL is probably the best Linux server distribution and CentOS is very much a like (except for the yearly fees).
This distribution (and Fedora as well) is very common for MySQL installation, since there are many predefined packages for it. This is unlike other distributions such as Ubuntu.

Therefore, when you will perform your database migration to the cloud, I recommend that you will first verify your needs. The following items will help you implement your systems right:

1. Select the Linux flavor
1. CentOS: Detailed options are available bellow. Don't forget to verify the recent CentOS version: Usually there are two (an early major version such as 6.0 and an old advanced minor version such as 5.7) and you should select the right version for you.
2. Fedora: Some free and good AMIs are available.
3. RHEL: There is a premium AMI for it
4. Ubuntu: No formal MySQL distribution exists to this flavor.
5. Debian.
2. Select the Storage Type. Amazon AMIs can store their information on one of two storage type:
1. Instance storage: this is a server attached disks storage that is great from plain performance issues (no network traffic and latency for storage). Yet, it lacks the option to extend the disk seamlessly to a larger size and backup must be done through the network instead on an instant disk duplication (shorter downtime).
2. EBS: this is Storage Area Network based disks that easily can be extended and backed up with minimal server downtime. Yet, this storage costs both in money (~$0.15/GB per month) and network latency.
3. Select the right image for you:
1. RightScale Image: (last update Jan 2009. If you don't use RightScale, don't forget to remove their management tools and don't forget to update your version to a recent one. RightScale has the two types of images.
2. Amazon Linux AMI: The AWS image is based on CentOS image, yet it includes some tweaks. The plus is having an Out of the Box solution with Amazon support. The minus is that it's not a 100% RHEL compatible anymore.
4. Install your database (MySQL probably) and web server (Apache probably) on the machine.
1. The recommended MySQL version is MySQL 5.5 with major performance enhancement since MySQL 5.1.

Bottom Line

Now, you just need is to choose the configuration that most fit your needs.

Keep Performing,

Moshe Kaplan

Moshe Kaplan is an entrepreneur and a cloud systems consultant