Compaq Infortrend Manuale Utente
RAID Planning
2-9
2.3.3 Making Arrays Available to Hosts
Figure 2 - 7
Mapping Partitions to Host ID/LUNs
Host ID mapping is a process that associates a logical configuration
of drives with a host channel ID/LUN. To avail logical partitions on
host channel(s), map each partition to a host ID or one of the LUNs
under host IDs. Each ID or LUN will appear to the host adapter as
one virtual hard drive.
of drives with a host channel ID/LUN. To avail logical partitions on
host channel(s), map each partition to a host ID or one of the LUNs
under host IDs. Each ID or LUN will appear to the host adapter as
one virtual hard drive.
There are alternatives in mapping for different purposes:
1. Mapping a logical configuration to IDs/LUNs on different host
channels allows two host computers to access the same array.
This method is applicable when the array is shared in a
clustering backup.
This method is applicable when the array is shared in a
clustering backup.
2. Mapping partitions of an array to IDs/LUNs across separate
host channels can distribute workload over multiple data paths.
3. Mapping across separate host channels also helps to make use of
all bandwidth in a multi-path configuration. Firmware
automatically manages the process when one data path fails and
the workload on the failed data path has to be shifted to the
existing data paths.
automatically manages the process when one data path fails and
the workload on the failed data path has to be shifted to the
existing data paths.
Figure 2 - 8
Mapping Partitions to LUNs under ID