Instruction Manual
Table Of Contents
- G2 Backup System user guide
- Contents
- 1 Getting started
- 2 Home, Summary
- 3 Virtual Tape Devices
- 4 NAS
- 5 Appliance Configuration
- 6 Status
- 7 Replication
- 8 Administration
- 9 Restore processes with replication
- 10 Restore processes without replication
- 11 Understanding LEDs
- 12 Hardware monitoring
- 13 Troubleshooting
- Connecting to the StoreOnce Backup System from the backup application
- Connecting to the network
- Using the 10Gb ports (HP D2D4300 Series only)
- Performance
- Web Management Interface errors and warnings
- Power On/Off Problems
- Cannot connect to Web Management Interface
- NFS State handle error
- Cannot authenticate an iSCSI session
- Diagnostic Fibre Channel device
- If the HP StoreOnce Backup System runs out of disk space
- Cannot access a storage shelf (HP D2D4100 and 4300 Series Backup Systems)
- If backup or replication fails
- Recovering Devices that have ‘failed to start’ or have become read-only
- StoreOnce Backup System configuration problems
- Upgrade licenses
- Replacement of hardware
- Upgrades to component parts
- 14 Hard disk replacement
- A Extra information for G1 products
- Glossary
- About this guide
- Index
14 Hard disk replacement
In this chapter:
• RAID
• How do I know a disk has failed?
• Replacing a hot-plug hard disk
• After replacing the failed disk
RAID
RAID 6
RAID 6 provides protection against double disk failures and failures while a single disk is rebuilding.
The following HP StoreOnce Backup Systems are RAID 6 devices.
• HP D2D4312 and HPD2D4324 Backup Systems
• HP D2D4106 and HP D2D4112 Backup Systems
The HP StoreOnce Backup System head unit is protected by a RAID 6 volume, and each Capacity
Upgrade Kit is protected by a separate RAID 6 volume. Therefore the head and each Capacity
Upgrade Kit can experience a double disk failure without incurring a data loss.
These HP StoreOnce Backup Systems also have an online spare disk on each shelf, which will
automatically be incorporated into the RAID if a disk fails. This means that actual storage capacity
is approximately 75% of the physical storage capacity for the main unit and each Capacity Upgrade
Kit connected to it.
• 18 TB for the HP D2D4324 Backup System and 18 TB for each of up to three Capacity
Upgrade Kits
• 9 TB for the HP D2D4312 Backup System and 9 TB for each of up to three Capacity Upgrade
Kits
• 9 TB for the HP D2D4112 Backup System and 9 TB for an attached Capacity Upgrade Kit
• 4.5 TB for the HP D2D4106 Backup System and 4.5 TB for an attached Capacity Upgrade
Kit
RAID 5
The following HP StoreOnce Backup Systems are RAID 5 devices.
• HP D2D2504 Backup Systems
• HP D2D2502 Backup Systems
RAID 5 stores parity data across all the physical drives in the array. If a drive fails, the controller
uses the parity data and the data on the remaining drives to reconstruct data from the failed drive.
The system continues operating with a slightly reduced performance until you replace the failed
drive. RAID 5 requires an array with a minimum of three physical drives. For the HP StoreOnce
Backup System, which has four disks, 25% of the total logical drive storage capacity is used for
parity data.
This means that actual storage capacity is approximately:
• 1.5 TB for the HP D2D2502i Backup System
• 3.0 TB for the HP D2D2504i Backup System
136 Hard disk replacement