バックアップ/リカバリでは、オンラインストレージ「Amazon S3」へ定期的にデータをバックアップ可能。また、遠隔地にあるNSx700シリーズ同士でバックアップや複製を実行するディザスタリカバリ環境を構築できる。バックアップツールとしては、米Acronis社のバックアップソフト「Acronis Backup ＆ Recovey」が付属するほか、Windows Backup UtilityやMac OS XのTime MachineといったOS標準ツールなどを利用できる。

SimpleDB Throttling

Now that you have created the requisite number of domains (say 100) that you need, you might think that you can just pump all this data into SimpleDB in a few hours,

Wrong!

Amazon imposes a concept of fairness on all users of the system. If you try to execute too many writes, Amazon starts returning 503 - Service Unavailable fast-fail responses to you. SDB throttles you.

How many put’s can you execute per second per domain?

My experience has been: 70 singleton puts/domain/sec

If you had 100 domains and could achieve 70 singleton puts/domain/sec, how long would it take you to forklift 1 Billion records?  It would take about 1.6 days.

In reality, the single put rate slows down the more full your domains become, so you don’t get this rate throughout.

Earlier this year, Amazon unveiled Batch Put . This gave me a 20x throughput improvement (I was inserting 20 items per batch put call) on nearly-empty domains. I did not trend how the batch put performed as my domains got more full, but my impression was that it was still much faster than the singleton put.

Now, if you have used PutAttributes or BatchPutAttributes, you will know that you can specify “replace=true” or leave the default “replace=false” option on each item. Leaving the default is much, much more efficient. If you know that you are fork-lifting brand new data, then this is the way to go.

■ SimpleDBへの書き込みのパフォーマンスは制限されている。
■ 70 singleton puts/ドメイン/秒
■ 503が返ったらエラー処理をしてリトライするなどする。
■ PutAttribues/BatchPutAttribuesの replaceはデフォルトを使う事。

EBS-backed AMIs have a life cycle more similar to that of real computers:

EBS-backed AMI instances begin their lives when launched, spending some time in the "pending" state until the order is fulfilled. When the instances start booting they are "running". From there they can be rebooted or shut down, like S3-backed AMI instances. They can also be "stopped" (such as with the ec2-stop-instances command), from which they can be started again (e.g. with the ec2-start-instances command) or terminated.

http://aws.amazon.com/ec2/ には、On Demand Instanceに関して、「 Pricing is per instance-hour consumed for each instance type, from the time an instance is launched until it is terminated. Each partial instance-hour consumed will be billed as a full hour. 」とあるので微妙なところ。ただし、Reserved Instanceに関しては「Instance-hours are billed for the time that instances are in a running state; if you do not run the instance in an hour, there is zero usage charge.」と書いてある。
Shutting-downになるとコントロール不能なので、多分課金されないのでは。

fstab に書いていないのは、起動時に /dev/sdb1 がマウントされているとは限らないからです。要は ec2-bundle-vol する前は /home を umount しておけ、ということですね。

Trends

The cloud marches forward! The past two months have been slower than usual (4-5% overall growth). On the one hand the cloud may have come in useful to handle the holiday traffic spikes, but on the other hand who wants to rock the boat at the most important time of the year, and just before your staff head out for vacation?

Website Edition

The Website Edition has everything you need to run a customer-facing website on the cloud with scalability and reliability.

Key Benefits

• Everything you need to run scalable websites in the cloud
• Autoscaling based on hardware and process-specific load metrics
• Fully customizable and extensible infrastructure
• Pre-designed ServerTemplates for fast deployment and time to market
• Deployment level management and automation
• Total control and transparency
• Cloud portability and interoperability
• Easy test and development using the clone environments option

Key Features

• Web-based Management Dashboard
• User permissioning
• Lifecycle Support
• Cloud-ready ServerTemplates
• Multi-deployment, multi-server cluster management
• Dynamic server configuration
• Autoscaling based on load metrics
• Load balancing front-ends
• Redundant database with failover and recovery
• Advanced graphical monitoring, alerting, and performance statistics
• Centralized logging
• Automated error handling and reporting

To find out more about deploying scalable websites with RightScale, visit our Cloud Computing Uses section.

実はこのとき、私はもういいやと思ってインスタンスを落としてしまい、一瞬身動きがとれない状態になった。作り直すのも業腹だと思い、しばらく考えて、一度ローカルに落として、ローカルのAMIツールで西海岸にあげなおした。

またデフォルトのイメージはFedoraだが、この中でCentOSなら割と簡単にイメージを作ることができる。アマゾンのマニュアルにも掲載されている。

しかし、作られたイメージは、インスタンスでは、そのイメージのカーネルが動くわけではなく、Xenのカーネルで動くのでモジュールが何もない状況になってしまう。そこでアマゾンから対応する専用のモジュールをダウンロードして、トップディレクトリで解凍してdepmod -aを実行するか再起動する。デベロッパーのサイトで議論されていた。でも、この部分がマニュアルに書かれていないのはなぜだろう。