Power Path Migration Enabler Host Copy

PPME requires powerpath fully installed and powerpath must manage the devices. However, multipathing license is not required, but server must be under powerpath maintainence. (a single active path while redundant paths are in an "unlicensed" state).

Powerpath can present devices as native devices or pseudo devices. Powerpath automatically creates pseudo devices in support operating system.
A pseudo device is a special device created by powerpath. Powerpath supports up to 32 paths per device. Powerpath supports pseudo devices on all platforms excpet HP-UX.

PPME steps:

1. Install Powerpath.
2. Install PPME license.
3. Identify source and target LUNs.
4. Zone and mask target LUNs to the host
5. Setup migration (use powermig setup)
6. Start bulk data copy and cloning of application writes. (use powermig sync)
7. Query migration status. (use powermig query)
8. Pause/Resume migration (use powermig pause/resume)
9. After copy completes, test the result by starting reads from target by moving from the source select state. (use powermig selectTarget)
10. Commit the migration (use powermig commit)
11. Clean up the migration (use powermig cleanup)
12. Remove the source device.

powermig command:

• setup - specifies the source and target devices and technolgy type used in the migration
• sync - starts data copy and write cloning process while application continues uninterrupted
• info - displays information about one or all migration sessions
• query - displays information about one migration sessions
• pause/resume - pasuse/resume a migration process
• throttle - change the bulk data rate for a migration
• abort - aborts a migration and returns the migration session to setup state
• selectSource - designates the source logical unit as the recipient of all I/O requests
• selectTarget - designates the target logical unit as the recipient of all I/O requests
• commit - commits the migration by permanently designating the target as the recipient of all I/O requests. Source device is no longer synchronized with the target
• undoredirect - stop redirection of I/O from source to target. Only use when source logical unit is a native device and application I/O is stopped.
• cleanup - removes selected data on the source or target logical unit so that the abandoned device is left in a safe state.
• getHandle - retrieves the handle for a migration session in progress
• version - displays PPME version on host.