Experience with AWS

Sean O Sullivan

LocalSocial / Dial2Do

Motivation

• Ease of use / Speed of use• Experimentation• AMIs• Flexibility• Pricing

LocalSocial

• S3– Stores our AMI– Fedora 8 from AWS– Plus all our own stuff (RoR, Scripts, …)

• EC2– One “small instance” Server

• 1.7 GB of memory, 1 EC2 Compute Unit (1 virtual core with 1 EC2Compute Unit), 160 GB of instance storage, 32-bit platform

– Runs our AMI fulltime– Two domains right now

• gigmonkey.com• mylocalsocial.com

– And our VPN• EBS

– Connected to running EC2 Instance– Persistent Store for all mySQL DBs

LocalSocial

Localsocial: VPN

LocalSocial: Tools etc.• Wrote some wrappers around the command line tools

– start_instance: start a new instance of our Base AMI– attach_database_volume: mount our EBS volume to our EC2 instance

• Gets a new instance running with the required EBS volume (with ourmySQL DB) mounted.

• Also have commands to do with bundling up the AMI. Used if we makesystem changes that want to reflect across all newly started instances.– Excludes our application code - this is deployed after the instance is started.

• Start to finish deploy– 1. Start new Instance of Base AMI– 2. Attach the DB EBS volume– 3. Setup our application environment (Capistrano deploy:setup)– 4. Deploy our application from our SVN repository.– 5. Restart services

• Backup tasks– backup : wraps the ec2 snapshot command (creates a snapshot of our

EBS volume)– Did this ourselves, but may use ec2onrails in future

Dial2Do: CloudFront

• Amazon's CDN service• Delivery of static assets

– e.g. images, javascript, stylesheets– Huge increase in speed (3x to 10x depending….)

• Drawback– Can't manually expire the local caches in CF– If you upload a new image it's fine– If you update a CSS file without changing it's name then the

change will not be picked up for 24 hours.• Workarounds

– Version every filename (a pain!),– Use multiple "buckets" in Amazon

Dial2Do: CloudFront

Dial2Do: Backups

• Backup to S3• Rotation policy

– 7 dailies– 5 weeklies– Monthlies (never rotated)

• Keeps the size maintainable– And the bill modest

Costs

• EC2– Running Small Instance

• $0.10 per instance-hour• 743 hours• $74.30 per month

• S3– 6-7Gb stored– Costs about $1 a month– $0.150 per GB

Costs

EC2 Dashboard

Wish List / to be done…

• Auto scaling• Cost management• Monitoring

Conclusions

• Nowadays: This stuff works!• Excellent for startups

– Contrast with “old days”• Killer combo

– Virtualisation– On-demand compute and storage

• Gets better month by month– The “grid” is becoming a reality