# New I/O flavors in ePouta

DevFeed: [New I/O flavors in ePouta](<https://devfeed.tech/articles/new-i-o-flavors-in-epouta-19753.md>)

Original publisher: [Read original article](<https://cloud.blog.csc.fi/2017/07/new-io-flavors-in-epouta.html>)

Author: Jukka Nousiainen (noreply@blogger.com)

Published: 2017-07-07T12:43:00Z

Content type: release

Language: en

Sources: [CSC - IT Center For Science - Cloud Team](<https://devfeed.tech/sources/csc-it-center-for-science-cloud-team.md>)

Topics: [cloud-infrastructure](<https://devfeed.tech/topics/cloud-infrastructure.md>), [IO](<https://devfeed.tech/topics/io.md>), [Persistence](<https://devfeed.tech/topics/persistence.md>), [Apache Cassandra](<https://devfeed.tech/topics/cassandra.md>), [datasets](<https://devfeed.tech/topics/datasets.md>), [Server](<https://devfeed.tech/topics/server.md>)

Tags: [cassandra](<https://devfeed.tech/tags/cassandra.md>), [clusters](<https://devfeed.tech/tags/clusters.md>), [cpouta](<https://devfeed.tech/tags/cpouta.md>), [epouta](<https://devfeed.tech/tags/epouta.md>), [persistence](<https://devfeed.tech/tags/persistence.md>), [ssd](<https://devfeed.tech/tags/ssd.md>), [storage](<https://devfeed.tech/tags/storage.md>)

## AI overview

The I/O Virtual Machine flavors previously released in cPouta are now available in ePouta. They use SSD-backed striped RAID0 storage, providing high I/O performance without persistence or VM health guarantees if a node or disk fails. They are suited to clustered software such as Hadoop and Cassandra, with anti-affinity server groups recommended for node separation.

## Source excerpt

About a year ago we released the I/O Virtual Machine flavors in cPouta. As of July, similar flavors are now also available in ePouta; you can find an exhaustive list here. The I/O flavors are provided with the same disclaimer as with their cPouta counterparts: both the root disk and the ephemeral disk for data storage are hosted on a striped (RAID0) array of SSD disks. That means you get a lot of I/O, but absolutely no guarantees for the persistence or health of VMs in case a node or a disk breaks. Thus these flavors are most natural to use with software which clusters nicely, such as Hadoop or Cassandra. To further ensure each VM in a cluster ends up on separate nodes, we recommend creating an anti-affinity server group.