Posted on by greg

Cloud conversations: AWS EBS, Glacier and S3 overview (Part II S3)

Storage I/O industry trends image

Amazon Web Services (AWS) recently added EBS Optimized support for enhanced bandwidth EC2 instances (read more here). This industry trends and perspective cloud conversation is the second (looking at S3 object storage) in a three-part series companion to the AWS EBS optimized post found here. Part I is here (closer look at EBS) and part III is here (tying it all together).

AWS image via Amazon.com

For those not familiar, Simple Storage Services (S3), Glacier and Elastic Block Storage (EBS) are part of the AWS cloud storage portfolio of services. With S3, you specify a region where a bucket is created that will contain objects that can be written, read, listed and deleted. You can create multiple buckets in a region with unlimited number of objects ranging from 1 byte to 5 Tbytes in size per bucket. Each object has a unique, user or developer assigned access key. In addition to indicating which AWS region, S3 buckets and objects are provisioned using different levels of availability, durability, SLA’s and costs (view S3 SLA’s here).

AWS S3 example image

Cost will vary depending on the AWS region being used, along if Standard or Reduced Redundancy Storage (RSS) selected. Standard S3 storage is designed with 99.999999999% durability (how many copies exists) and 99.99% availability (how often can it be accessed) on an annual basis capable of two data centers becoming un-available.

As its name implies, for a lower fee and level of durability, S3 RRS has an annual durability of 99.999% and availability of 99.99% capable of a single data center loss. In the following figure durability is how many copies of data exist spread across different servers and storage systems in various data centers and availability zones.

cloud storage and object storage across availability zone image

What would you put in RRS vs. Standard S3 storage?

Items that need some level of persistence that can be refreshed, recreated or restored from some other place or pool of storage such as thumbnails or static content or read caches. Other items would be those that you could tolerant some downtime while waiting for data to be restored, recovered or rebuilt from elsewhere in exchange for a lower cost.

Different AWS regions can be chosen for regulatory compliance requirements, performance, SLA’s, cost and redundancy with authentication mechanisms including encryption (SSL and HTTPS) to make sure data is kept secure. Various rights and access can be assigned to objects including making them public or private. In addition to logical data protection (security, identity and access management (IAM), encryption, access control) policies also apply to determine level of durability and availability or accessibility of buckets and objects. Other attributes of buckets and objects include life-cycle management polices and logging of activity to the items. Also part of the objects are meta data containing information about the data being stored shown in a generic example below.

Cloud storage and object storage spread across availability zones figure

Access to objects is via standard REST and SOAP interfaces with an Application Programming Interface (API). For example default access is via HTTP along with a Bit Torrent interface with optional support via various gateways, appliances and software tools.

Cloud storage and object storage IO figure
Example cloud and object storage access

The above figure via Cloud and Virtual Data Storage Networking (CRC Press) shows a generic example applicable to AWS services including S3 being accessed in different ways. For example I access my S3 buckets and objects via Jungle Disk (one of the tools I use for data protection) that can also access my Rackspace Cloudfiles data. In the following figure there are examples of some of my S3 buckets and objects used by different applications and tools that I have in various AWS regions.

Image of AWS S3 usage
AWS S3 buckets and objects in different regions

Note that I sometimes use other AWS regions outside the US for testing purposes, for compliance purpose my production, business or personal data is only in the US regions.

The following figure is a generic example of how cloud and object storage are accessed using different tools, hardware, software and API’s along with gateways. AWS is an example of what is shown in the following figure as a Cloud Service and S3, EBS or Glacier as cloud storage. Common example API commands are also shown which will vary by different vendors, products or solution definitions or implementations. While Amazon S3 API which is REST HTTP based has become an industry de facto standard, there are other API’s including CDMI (Cloud Data Management Interface) developed by SNIA which has gained ISO accreditation.

Cloud storage and object storage I/O figure
Cloud and object storage access example via Cloud and Virtual Data Storage Networking

In addition to using Jungle Disk which manages my AWS keys and objects that it creates, I can also access my S3 objects via the AWS management console and web tools, also via third-party tools including Cyberduck.

Cyberduck tool.

Additional reading and related items: