#!/bin/bash
#-----------------------------------------------------------------------------
# ec2-rsync.sh
# Creates an Amazon Machine Instance (AMI) and attaches my Elastic Block
# Storage (EBS) volume to it. Then runs rsync to upload the specified 
# directories to the volume for backup. 
# NOT IMPLEMENTED YET: When complete the volume is then
# copied to an S3 Snaphot which is more robust than a normal EBS volume.
#
# The volume is then detached and the AMI shutdown.
#-----------------------------------------------------------------------------

# aws uses curl for all communication with the Amazon servers. It must be able
# to find a CA certificate bundle to authenticate the server.
export CURL_CA_BUNDLE=/etc/ssl/certs/cacert.pem

# This is the name of the image I will be using. It is an ubuntu 8.10
# intrepid base image.
#export EC2_IMAGE=ami-2810385c
export EC2_IMAGE=<YOURAMIID>

# This is my single EBS volume identifier. I only have one at the moment.
# Not sure how to manage more than one in the future?
export EC2_VOLUME=<YOURVOLID>

# Create a running instance, parsing the output to find the instance
# identifier and host name.
export EC2_INSTANCE=`aws run-instances --wait $EC2_IMAGE \
    -z eu-west-1a -k gsg-keypair | \
    sed -e 's/ *//g' | tr '\t' '\n' | grep -m 1 '^i-'`
echo "Instance started with ID $EC2_INSTANCE"

export EC2_HOST=`aws describe-instances $EC2_INSTANCE | \
    sed -e 's/ *//g' | tr '|' '\n' | grep amazonaws.com`
echo "Host name is $EC2_HOST"

# this is the sed script required to extract the RSA fingerprint from the
# console output
RSA_FP=`aws get-console-output $EC2_INSTANCE | \
    grep '/etc/ssh/ssh_host_rsa_key.pub (RSA)' | \
    sed 's/^ec2: 2048 //' | \
    sed 's| /etc/ssh/ssh_host_rsa_key\.pub (RSA)||'`
while [ -z "$RSA_FP" ]
do
    echo "No console output yet, retrying..."
    sleep 30
    RSA_FP=`aws get-console-output $EC2_INSTANCE | \
        grep '/etc/ssh/ssh_host_rsa_key.pub (RSA)' | \
        sed 's/^ec2: 2048 //' | \
        sed 's| /etc/ssh/ssh_host_rsa_key\.pub (RSA)||'`
done
export RSA_FP
echo "The RSA fingerprint of the new server is $RSA_FP"

# attach the EBS volume under /dev/sdh. Sometimes this isn't
# instant so sleep for 30s to give it time
aws attach-volume $EC2_VOLUME -i $EC2_INSTANCE -d /dev/sdh
sleep 30

# ssh in to create a mount point for the volume
ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null \
    -i ~/.ec2/id_rsa-gsg-keypair root@$EC2_HOST \
    "mkdir /mnt/store && mount /dev/sdh /mnt/store"

# rsync the specified directory. Consider parameterising this/these locations
# into a config file.
rsync -e "ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null -i /home/gordon/.ec2/id_rsa-gsg-keypair" \
    -avz --delete-after \
    /shares/internal/photos/ \
    root@$EC2_HOST:/mnt/store/photos/ > rsync.log
    
ssh -o StrictHostKeyChecking=no -o UserKnownHostsFile=/dev/null \
    -i ~/.ec2/id_rsa-gsg-keypair root@$EC2_HOST \
    "umount /mnt/store"
    
# detach the volume and shutdown the instance    
aws detach-volume $EC2_VOLUME -i $EC2_INSTANCE
aws terminate-instances $EC2_INSTANCE
echo "Terminated instance with ID $EC2_INSTANCE"

# create a snapshot of the volume.