1.7 Availability

Your users must be able to access network data on demand. Your storage solution must remain available through server, connection, and device failures. Automatic failover solutions empower you to set failover policies so that the network continues to work transparently to users whenever a failures occur.

Beyond the day-to-day failures and outages, most businesses today must provide high availability solutions and business continuance solutions to ensure continuous data access and network security in the event of site failures and disasters. Your solution should ensure that your mission-critical data is never at risk.

Storage Requirement

Novell OES Solution

High availability of access to data in the event of server failure: The ability to provide highly available solutions to allow users and applications to access data via alternate servers in the event of server failure.

Novell Cluster Services supports up to 32 cluster nodes for service and storage failover in the cluster. It also supports web service-enabled failover, quarantine of failing service, maintenance mode, and XML (Extensible Markup Language) management. A read-only shared cluster volume capability is also available.

For information, see the OES 11 SP2: Novell Cluster Services for Linux Administration Guide.

High availability of access to data in the event of connection or device failure: The ability to provide highly available solutions to allow users and applications to access data via alternate routes or resources.

NSS supports both Fibre Channel (FC) and iSCSI SAN solutions. It also supports full Novell Cluster Services with devices in SAN solutions.

The Linux operating systems can boot with the system volume on a local hard drive or on a Fibre Channel storage device if your server BIOS supports booting from a SAN. Booting from an remote storage device allows you to immediately swap out server hardware in the event of a disaster and directly boot without re-installing the operating system. The automatic hardware detection in the operating system allows for a new server to have updated or different controllers when booting from a FC SAN.

For information about using iSCSI on Linux, see Mass Storage Over IP Networks: iSCSI in the SLES 11 SP3 Storage Administration Guide..

High availability of access to data in the event of device failure: The ability to provide highly available solutions to allow users and applications to access data via alternate routes in the event of a single device failure.

NSS supports software RAIDs 1 (mirroring) and 5 (striping with parity), which allow a single device failure at a time without data loss. It also supports complex nesting RAIDs, such as software RAIDs 10 and 15.

For information, see Managing NSS Software RAID Devices in the OES 11 SP2: NSS File System Administration Guide for Linux.

High availability of access to data in the event of connection failure: The ability to provide highly available solutions to allow users and applications to access data via alternate routes in the event of connection failure.

Multipath I/O solutions allow for redundant storage interconnects in all storage architectures. It automatically identifies all paths and lets you set the primary path and priorities for failover sequence to the alternate paths. Failover is automatic.

For Linux, see Managing Multipath I/O for Devices in the SLES 11 SP3 Storage Administration Guide.