Rivals are gonna have to stop sniping at OpenStack for only having object storage.

Rackspace, which originally put the open source cloud platform in play, filled the gaping hole Tuesday with its new Cloud Block Storage solution. The rest of the OpenStack community will catch up eventually thanks to the Cinder Project.

The widgetry will give Rackspace and friends a more competitive position vis-à-vis their great nemesis Amazon, whose Elastic Block Storage (EBS) has been around for a while.

Rackspace says its Cloud Block Storage was designed for more consistent performance in the cloud than competitive solutions, with infinite scalability and a very simple pricing model.

CTO John Engates, responsible for building the block storage from scratch, reckons Rackspace will get a lot more companies to adopt its OpenStack-based cloud because it will be available to a lot more applications. He wasn’t willing to guess how much new business however. He claims Rackspace has the second biggest cloud after Amazon with tens of thousands of enterprise users.

The widgetry promises a superior approach to attached storage in the cloud with reliable performance for file systems, databases and other I/O-intensive applications. It can be used by companies accessing lots of large files, small to medium-size web sites, and archiving.

Engates said the storage has been used internally but its announcement was delayed so that Cinder, the open source project named after cinder blocks, could catch up and its APIs exposed.

Rackspace claims its pricing is competitive with EBS when you consider that Rackspace support is bundled in.

Standard SATA disk storage is supposed to run 15 cents a gigabyte a month and faster, inherently more expensive flash-based storage, good for self-managed MySQL databases, MongoDB, Cassandra and web caching and indexing, will run 70 cents a gigabyte a month.

Amazon’s block storage doesn’t include a SSD option although it doubtless will soon enough.

Rackspace’s snapshot storage cost 10 cents a gigabyte a month.

There’s no charge for I/O, no additional per-instance fee, no minimum instance size, and pricing’s the same in all US regions.

The widgetry, also available in the UK, is available now for OpenStack-powered Cloud Servers, Rackspace’s version of EC2.

Users can attach multiple volumes of up to 1TB each of block storage to the Cloud Servers and detach and reattach storage between compute nodes reportedly in seconds. High performance can be achieved without having to RAID0 (stripe) volumes together, savings cost and complexity. There’s also no cap on I/O and users don’t have to specify IOPS numbers, as they do with competing solutions.

Cloud Block Storage Standard volumes are aimed at customers that typically require large amounts of everyday storage, including those who want to scale storage without scaling compute nodes.

By the way, the OpenStack version Rackspace is using is half-way between Folsom, the current version and Grizzly, the next version.