Using Disk Roaming; Fastpath; Virtual Disk Migration - Dell PowerEdge H730P User Manual

CAUTION: Do not attempt disk roaming during RAID level migration (RLM) or online capacity
expansion (OCE). This causes loss of the virtual disk.

Using Disk Roaming

Perform the following steps to use disk roaming:
1. Turn off the power to the system, physical disks, enclosures, and system components.
2. Disconnect power cables from the system.
3. Move the physical disks to desired positions on the backplane or the enclosure.
4. Perform a safety check. Make sure the physical disks are inserted properly.
5. Turn on the system.
The controller detects the RAID configuration from the configuration data on the physical disks.

FastPath

FastPath is a feature that improves application performance by delivering high I/O per second (IOPs) for
the Solid State Drives (SSD). The Dell PowerEdge RAID Controller (PERC) H730P supports FastPath.
To enable FastPath on a virtual disk the Dell PowerEdge RAID Controller (PERC) H730P cache policies
need to be set to Write-Through and No Read Ahead. This enables FastPath to use the proper data path
through the controller based on command (read/write), IO size, and RAID type.
For small random workloads, like OLTP, a RAID 10 array provides high performance and for sequential
read dominate workloads, a RAID5 array provides high performance.
NOTE: Only IO block sizes smaller than virtual disk's stripe size are eligible for FastPath.
NOTE: The Physical Disk Power Management feature is not applicable to FastPath-capable virtual
disks.

Virtual Disk Migration

The PERC H730P card supports migration of virtual disks from one controller to another without taking
the target controller offline. The controller can import RAID virtual disks in optimal, degraded, or partially
degraded states. You cannot import a virtual disk that is offline. Disk migration pointers:
• Supports migration of virtual disks from PERC H310, H710, H710P, and H810 to PERC H730P
• Supports migration of volumes created within PERC H730P
• Does not support migration from PERC H730P to H310, H710, H710P, H810
NOTE: The source controller must be offline prior to performing the disk migration.
NOTE: Disks cannot be migrated to older generations of the PERC cards.
NOTE: Importing secured virtual disks is supported as long as the appropriate Local Key
Management (LKM) is supplied or configured.
When a controller detects a configured physical disk, it flags the physical disk as foreign, and generates
an alert indicating that a foreign disk was detected.
19