Exanodes for Linux is a first step into the world of Shared Internal Storage. It allows applications to use disks embedded in given servers as if they were a powerful traditional external array. Reliable, efficient and easy to manage, Exanodes for Linux is the perfect complement to SAN and NAS systems in HPC, Test & Development, and Hosted Services infrastructures.
Exanodes is a software solution which creates a shared storage system using the cluster’s own hard disks which are, customarily, under-used. Exanodes utilizes the network interconnect as a datapath and both the nodes’ memory and CPU to process storage access requests.
The internal storage is clustered, allowing the user to share data among clusters’ nodes using a reliable, high-performance method. Exanodes is perfectly suited to the needs of cluster environments as it has been based on both their architecture and philosophy.
Thanks to its versatility and high performance, Exanodes proves to be the ideal storage solution for Linux clusters. Since it is non-intrusive and can be easily implemented alongside other storage solutions, Exanodes’ integration is quick and easy and in no way affects previous solutions.
Exanodes provides file systems with storage volumes accessible in block mode (LUN). The LUNs generated by Exanodes have all the features of a LUN generated by a classic storage array. Exanodes makes it possible to partition the virtual array (the very definition of a LUN), and to allocate partitions to specific nodes or mask them (as in LUN masking), in a totally seamless way.
According to user requirements, Exanodes can be configured in either symmetric mode or asymmetric mode:
Exanodes provides Linux cluster users with a high-performance clustered storage system which is economical and easy to manage.
A Storage System with High Parallelism - With Exanodes, the processing of inputs/outputs is carried out simultaneously on a large number of nodes. The application therefore benefits from cluster parallelism for computing as well as for storage.
Fine Tuning for Higher Performance Levels - In order to deliver the storage solution that matches the application’s needs, Exanodes’ technological components can be fine-tuned to achieve higher performance levels (e.g. data layout, network use, balance between I/Os, computing, etc.).
Natural scalability - With Exanodes, by simply adding a node to a cluster you increase both your computing and storage performance.
A Highly Adaptable Hardware Configuration - Exanodes allows you to combine and use all types of storage devices accessible in block mode. (i.e. SATA or SCSI disks, software and hardware RAIDs, etc.)
Data Availability - To increase data availability, Exanodes provides a RAIN storage system (Redundant Array of Inexpensive Nodes). As every byte of information is replicated on another distinct node, if a node fails Exanodes’ RAIN system is able to carry on as normal with request processing, and both applications and users continue to have smooth uninterrupted access to their data.
Data Protection - Exanodes can virtualize any internal RAID on the clusters’ nodes. By combining the protection of internal RAIDs with the protection offered by RAIN, Exanodes provides highly reliable storage which can withstand numerous disk failures.
Exanodes stands out in the crowd of high-performance storage solutions because it is simple to set up, maintain and administer on a day-to-day basis. It simplifies several aspects of application management such as the redevelopment of applications designed for an SMP architecture into cluster-type applications.
Shared Storage System - Exanodes has all the advantages of a shared storage system accessible by each and every node of a given cluster and as a consequence data management is greatly facilitated. For example, using Exanodes: • the applications can be executed on any node within the cluster and their data can be easily accessed. • applications are truly mobile within a cluster because the data no longer has to be loaded to the nodes where the applications are being executed. • computing results are accessible from any node, removing the need to stage out the results after the computing phase.
Compliance with Standards - Exanodes has an exceptionally rich compatibility matrix. Exanodes supports • all major high performance networks - Infiniband, Gigabit Ethernet, SCI… • Linux private file systems - ext2, ext3, XFS, JFS… • clusterized file systems - GFS, Lustre, GPFS… • all types of block devices – disk partitions or whole disks, PATA, SATA, SCSI, JBOD, hardware RAID, software RAID, RAM...
Respect of Existent System - Exanodes is non-intrusive. Applications access Exanodes’ high-performance storage area without any need for reprogramming. Moreover the installation of Exanodes requires no modification to the Linux kernel.
Simplified Administration - The day-to-day administration of Exanodes is very simple. Numerous functionalities allow the user to efficiently manage the various storage volumes (supervision of logical volumes and file systems, hot-resizable logical volumes, access rights’ management etc.).
The user has the choice between 2 modes of administration: • a CLI mode • a GUI mode which simplifies the administration and supervision of the storage infrastructure
Switching from SMPs to Linux clusters is only truly worthwhile if the monetary investment in storage remains reasonable and if the administration of the system as whole is not too expensive in terms of man hours. To each of these points, Exanodes has a pertinent answer.
Drastic Reduction in External Storage Needs (SAN or NAS) - Confined to less demanding uses - such as: archiving computing results, data distribution for workflows involving several clusters, management of backups - external storage investment costs drastically reduce through the implementation of Exanodes.
Reduction in Operating Costs - The simplicity of the Exanodes solution (eg. integration and day-to-day management) means an increase in the amount of storage and computing nodes that can be managed by one person.
Simplified Computing Applications - Shared storage significantly reduces the cost of migration to cluster technologies by simplifying the way in which computing applications are developed and maintained. With Exanodes, data is now accessible from any node on a given cluster, so the way in which the data is placed and migrated within the cluster is immaterial and no longer needs to be specified in the application.
