ec2-snap-db

Wrapper script for ec2-consistent-snapshot that allows volume ids to be determined on the fly based on mount points in a configuration file (defaulting to /etc/default/ec2-snap-db).

Supports LVM and RAID devices in addition to normal block devices.

Requires installation of ec2-consistent-snapshot and the Amazon EC2 API Tools in the PATH.

Installation

Copy the files ec2-instance-env, ec2-snap-db, and ec2-volumes-for-mount to your directory of choice. Ensure that they have executable permissions for the user who will be running the process (0755 with root ownership should be fine). All three files must be installed in the same directory.

You may find it convenient to install these files in the same directory as either ec2-consistent-snapshot or the Amazon EC2 API Tools (e.g. /opt/aws/bin) to avoid having to update the PATH.

Usage

To run ec2-snap-db for testing purposes, execute it as follows:

ec2-snap-db --verbose --config /path/to/config

If the command is not run as root, it will attempt to use sudo to execute ec2-consistent-snapshot.

When the --config parameter is not passed, the default configuration file at /etc/default/ec2-snap-db will be used (if it exists).

To run from cron, copy the file examples/ec2-snap-db.cron to /etc/cron.d/ec2-snap-db and edit it to meet your needs.

Configuration

The configuration file for ec2-snap-db is a standard shell script. By default, it will be loaded from /etc/default/ec2-snap-db. The config file is expected to set the following environment variables:

• The AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY variables are used to call ec2-consistent-snapshot with the appropriate access credentials. They are also translated into AWS_ACCESS_KEY and AWS_SECRET_KEY for the calls to ec2-describe-volumes and ec2-describe-tags. These credentials must allow the ec2:CreateSnapshot, ec2:DescribeTags, and ec2:DescribeVolumes actions to be executed for the instance on which ec2-snap-db is run.

• The SNAP_DB_MOUNTS variable is an array containing the list of mount points to snapshot.

• The SNAP_DB_OPTIONS variable is an array containing additional options to be passed to ec2-consistent-snapshot, e.g. MySQL or Mongo-related parameters.

• The SNAP_DB_PREFIX variable controls the prefix used for the snapshot description. The default value is the value of the instance's Name tag or instance id. If the value contains a single '%s', the instance name will be subsituted into that position in the prefix.

A sample configuration file can be found at examples/ec2-snap-db.default.

NOTE: Your configuration file will contain AWS secrets, so its permissions should not allow other users to access the file. Owner-only permissions (e.g. 0600) are recommended.