HP Netserver LXr 8500 NetRAID-3Si Install Guide

NetRAID Supplement to the HP NetServer Microsoft Cluster Installation Guide 21
Set Array Parameters
After the array has been defined, set its parameters as follows:
1. Click Next.
The wizard displays its Logical Drive Definition window.
2. This window shows the array’s RAID level and its usable size.
NOTE Since all data is duplicated, the size of the array is one-half the sum of the capacity of the
two drives composing the array.
3. Click Advanced and set the Write Policy to Write Thru. Click OK.
4. If you are creating a RAID 1 array, press Accept. If you are creating a RAID 10 array, check the
Span Arrays box, then press Accept.
5. If you:
•
want to define another array, click Back and repeat the steps listed in "Define an Array" above
starting with step 3.
•
have identified all your arrays, click Next, Finish, and then OK.
NetRAID Assistant saves the array configuration and prompts that the array configuration has
changed. Click OK.
Initialize the Array
After you have defined the cluster’s arrays, initialize the arrays you defined. HP NetRAID Assistant
initializes all arrays at the same time.
To initialize the arrays:
1. Click OK at the Would you like to Initialize? prompt.
HP NetRAID Initialization may be time consuming. Plan on 5 to 15 minutes per array.
2. When initialization is complete, exit NetRAID Assistant.
Setup RAID 5 and 50 Arrays
Each RAID 5 disk array is composed of at least three hard (hot swap) drives located in external shared
storage cabinets. RAID level 5 (striping with distributed parity) provides storage redundancy with good
overall performance and a minimum loss in storage capacity. With RAID 5 the equivalent of only one hard
drive in the array is used for redundancy.
The following table shows how data is distributed for a RAID 5 array of three disks. Each stripe has one
block assigned to store parity data. Parity data is used to reconstruct the data on that stripe if one of the disks
fails. Parity information is distributed equally among all disk drives to equalize data I/O and achieve better
overall performance.
Raid Level 5 Parity Distribution
Stripe Disk 1 Disk 2 Disk 3
1 Block 1.1 Block 1.2 Parity 1
2 Block 2.1 Parity 2 Block 2.2
3 Parity 3 Block 3.1 Block 3.2