Alternate Operating System Support Improved with i5/OS V6R1
February 4, 2008 Timothy Prickett Morgan
To a certain way of thinking about it, the System i server is not an operating system running on a piece of hardware. It is a hybrid machine that runs a collection of operating systems (i5/OS, AIX, and Linux) running on Power processors. The box can also support other operating systems (Windows and Linux) on inboard or outboard System x servers that are all linked into the same storage infrastructure either under the skins of the server or attached to it through iSCSI adapters or Fibre Channel links to storage area networks.
As part of the rollout of i5/OS V6R1 last week, IBM made good on its promise to make externally linked System x rack and tower and BladeCenter blade servers play nicely with VMware‘s ESX Server 3 virtual machine hypervisor and its VMotion live migration feature for partitions running on X64 servers. Last fall, with the i5/OS V5R4M5 update, IBM worked with VMware to create drivers for the ESX Server hypervisor that would allow it to use the disks attached to System i servers as a storage area network. This support is important since a lot of the neat features of the VMware Virtual Infrastructure 3 stack of management tools for the ESX Server hypervisor are dependent on physical and virtual servers to be linked to shared storage linked to the servers either through iSCSI or Fibre Channel links. Now, with V6R1, not only can the System i platform function as a SAN for ESX Server instances, but now the VMotion feature works, too. That means companies with System x and BladeCenter machines can ricochet their Windows, Linux, and Solaris instances around the physical X64 boxes that are using the System i for storage. VMware’s HA and DRS high availability extensions, part of the Virtual Infrastructure stack, can also run in conjunction with the System i now, too.
Servers attached to the System i through the iSCSI adapters, which first started shipping in May 2006 and which replace proprietary links between the System i and a more limited number of System x servers, now support a wider variety of Linux and Windows platforms, too. As part of the V6R1 rollout, IBM is adding support for Microsoft‘s future “Longhorn” Windows Server 2008 operating system. Novell‘s 64-bit implementation of SUSE Linux Enterprise Server 10 and Red Hat‘s 64-bit Enterprise Linux 5 instances are also now supported on iSCSI-linked servers. (Previously, only 32-bit versions of the software were certified to use the System i for storage.) SUSE Linux customers also are getting a new file-level backup and save-while-active extension from i5/OS V6R1, which allows running 64-bit SLES 10 instances running on X64 servers and using the System i for disk to be backed up and archived.
RHEL and SLES instances running on the Power processors inside the box itself can be backed up at the file level as well using this new feature. IBM added that the 64-bit versions of SLES 10 and RHEL 5 are now available on logical partitions on the Power processors, too.
Windows also got some improvements with V6R1, and a feature called Storage Space Snapshots allows a concurrent save of data on Windows servers running on Integrated xSeries Server co-processors or attached to the System i box through Integrated xSeries Adapters or iSCSI links to be done without shutting down Windows or its applications.
Finally, using iSCSI links between System x servers and outboard System x and BladeCenter servers no longer requires an Ethernet switch between the two sets of machines. Now, the link can be direct between the X64 server and the System i, requiring only an Ethernet cable and the two iSCSI adapters.
Just in case you missed it in our other coverage of i5/OS V6R1, that operating system will begin shipping on March 21.