|A P P E N D I X D|
This appendix contains information that supplements the procedures in this guide.
A redundant array of independent disks (RAID) is a collection of drives that:
These servers include LSI Logic’s Integrated RAID solution, which supports the integrated mirroring (IM) type of RAID.
|Note - LSI Logic’s Integrated RAID solution also supports integrated striping (IS) but this option is not supported on the servers.|
LSI Logic offers an integrated RAID solution by simplifying the IM configuration options and by providing firmware support in its host adapters. The software continuously monitors IM volumes and reports status and error conditions as they occur.
Integrated RAID provides the following benefits:
|Note - LSI Logic provides a BIOS-based configuration utility that enables you to configure the mirroring attributes during initial setup and to reconfigure them in response to hardware failures or changes in the environment. Refer to Appendix C of this guide for more information about this utility.|
With traditional mirroring (or RAID1), a hard disk drive has its data duplicated on two different drives using either a hardware RAID controller or software (generally by means of the OS). If either drive fails, the other continues to function as a single drive until the failed drive is replaced.
|Note - To prevent data corruption on Solaris ZFS or Linux operating systems, create IM volumes before you install the OS. To create IM volumes use the LSI Configuration Utility.|
With integrated mirroring enhanced (IME) (also referred to as either Enhanced RAID1 or RAID1E), instead of being able to use only two drives, you can use two to six drives, including the option of using an odd number of drives. Instead of mirroring at the disk level, the data is mirrored in stripes across the drives. Thus, IME allows for more flexibility with mirroring data.
The LSI Logic integrated mirroring (IM) feature provides data protection for the system boot volume to safeguard critical information such as the OS on servers. Integrated mirroring provides simultaneous mirroring on configurations of two to six disks, to ensure fault-tolerant, high-availability data.
If a disk fails, the hot-swap capability allows the system to be easily restored by simply swapping disks. The system then automatically re-mirrors the swapped disk. Additionally, the hot-spare feature keeps one disk ready to automatically replace a failed disk in the volume, making the system even more fault-tolerant.
The mirroring is accomplished through the firmware of an LSI Logic controller that supports the standard Fusion-MPT interface. The runtime mirroring of the boot disk is transparent to the BIOS, drivers, and OS. Host-based status software monitors the state of the mirrored disks and reports any error conditions. The system is configured with a second disk as a mirror of the first primary disk.
The IM feature uses the same device drivers as the standard controllers, providing seamless and transparent fault tolerance. This eliminates the need for complex backup software or expensive RAID hardware. The IM feature operates independently from the OS, in order to conserve system resources. The BIOS-based configuration utility makes it easy to configure a mirrored volume.
Zero-channel RAID cards are RAID controller cards that utilize the SCSI chip on the motherboard to configure more advanced RAID setups. These servers do not support zero-channel RAID cards.
This option is for Sun Fire V40z servers only.
To achieve other RAID levels not supported by the on-board LSI controller, you can control the internal drives with a RAID card by routing the SCSI cable to it. Cabling a full-function RAID card to the internal drives is supported on the Sun Fire V40z server by routing a standard cable from the backplane to PCI slot 1.
|Note - An extender cable attached to the existing cable allows connection to a RAID card in PCI slot 1. Slot 1 is the half-length, horizontal slot under the power-supply cage assembly.|
You cannot use the LSI Configuration menu to mirror hard disks containing a type 8e partition.
If you try to mirror two internal hard disks using the on-board RAID features of the LSI 1030 controller, and if the primary disk contains a partition of type 8e (Linux Logical Volume Manager), you will see this message:
Can’t keep data. Incompatible partition. Press DELETE if data loss OK or any other key to cancel
As a workaround, change the partition type as follows:
1. Open a terminal window.
2. Become root user.
3. Type fdisk -l and note which partition has the ID 8e.
4. Type fdisk /dev/sda (the drive sda is shown as an example).
5. At the prompt Command (m for help): type t.
6. At the prompt Partition number (1-4): type the partition number resulting from the previous step.
For example, type 4 if /dev/sda4 was displayed as the LVM partition.
7. At the prompt Hex code (type L to list codes): type 83.
8. At the prompt Command (m for help): type w. Wait until the Syncing disks message is finished.
9. Reboot the system.
10. After rebooting, check whether the partition type is correct.
11. Reboot the system again and start the LSI configuration utility.
Before building the RAID, use the Restore defaults option.