Amazon EC2

Amazon's Cloud provides a flexible platform to deploy Eden scalably.

The costs aren't fixed & can be difficult to predict, despite their ​calculator, but are competitive, especially in Singapore, which is a good base for the Asia Pacific region.

Regions & Zones

Amazon supports multiple Regions in order to provide a service closest to your users.

• Namespaces of Instances, Volumnes & Snapshots are unique only within a Region.
• Within each Region, there are a couple of Availability Zones to allow spreading the risk across different facilities.
• Volumes are located within a specific Availability Zone
• Bandwidth transfers are free within an Availability Zone

Instance Size

• The free starter 'micro' instance is flexible as it can run both 32-bit & 64-bit Operating Systems.
• The normal production 'small' instance can only run 32-bit.
• Larger production instances can only run 64-bit, so can't have the exact same image used.
• The community Debian Squeeze AMI seems a fine base & attached scripts turn this into an Eden instance

Instance Persistence

• EBS-backed instances have persistent storage even whilst powered down, which is very useful.
• Each time you start an instance up, it will be assigned a new IP ('Public DNS')

Authentication

This can provide an early stumbling block.

• Each instance created needs to start with a unique SSH keypair
• When setting up an instance, be sure to safely download the private key.
• In order to get the public key (needed by SecureCRT for instance) then you need to login using CLI & retireve it:

  ssh -l root -i private.pem <hostname>
  cat ~/.ssh/authorized_keys
  

SecureCRT needs the private key storing as <filename> & the public as <filename.pub> (all on one line)

CLI Management

There are extensive CLI tools available to manipulate your instances.

• Java CLI for Windows/Linux
  • ​http://aws.amazon.com/developertools/351
  • ​http://serktools.com/2009/05/19/setting-up-ec2-command-line-tools-on-windows/
  • ​http://docs.amazonwebservices.com/AWSEC2/latest/CommandLineReference/
• Python: ​http://libcloud.apache.org

Growing Storage

1Gb EBS is too small for Eden - need to grow to 3Gb

# --region ap-southeast-1
set EC2_URL=https://ec2.ap-southeast-1.amazonaws.com
# Stop Host
ec2stop i-c75af292
# Create a snapshot
ec2-create-snapshot vol-e189e88c
# Create new volume from snapshot
ec2-create-volume -z ap-southeast-1b --size 3 --snapshot snap-63f89d08
# Attach new volume as secondary
ec2-attach-volume -i i-c75af292 vol-a9c2a3c4 -d /dev/sdb1
# Start Host
ec2start i-c75af292
ec2-describe-instances
# Login (Remember different IP!)
mkdir /mnt/data
echo '/dev/xvdb1 /mnt/data ext3 defaults,noatime 0 0' >> /etc/fstab
mount /mnt/data
resize2fs /dev/xvdb1
umount /mnt/data
# Stop Host
ec2stop i-c75af292
# Unattach volumes
ec2-detach-volume -i i-c75af292 vol-e189e88c
ec2-detach-volume -i i-c75af292 vol-a9c2a3c4
# Attach volume as boot
ec2-attach-volume -i i-c75af292 vol-a9c2a3c4 -d /dev/sda1
# Start Host
ec2start i-c75af292
ec2-describe-instances
# Login (Remember different IP!)
df -h