HP (Hewlett-Packard) QR516B Manuale Utente
Figure 10 LUN Set to Round Robin
Managing a round robin I/O path policy scheme through the VI/vSphere client GUI for a large
network can be cumbersome and challenging to maintain because the policy must be specified
for each LUN individually and updated whenever new devices are added. Alternatively, VMware
provides a mechanism whereby the server administrator can use esxcli, vCLI, or vSphere
Management Assistant (vMA) commands to manage I/O path policy for storage devices on a
per-host basis using parameters defined within a set of native ESX/ESXi storage plugins.
network can be cumbersome and challenging to maintain because the policy must be specified
for each LUN individually and updated whenever new devices are added. Alternatively, VMware
provides a mechanism whereby the server administrator can use esxcli, vCLI, or vSphere
Management Assistant (vMA) commands to manage I/O path policy for storage devices on a
per-host basis using parameters defined within a set of native ESX/ESXi storage plugins.
The VMware native multipathing has two important plugins: a Storage Array Type Plugin (SATP)
that handles path failover and monitors path health, and a path-selection plugin (PSP) that chooses
the best path and routes I/O requests for a specific logical device (PSP defines the path policy).
that handles path failover and monitors path health, and a path-selection plugin (PSP) that chooses
the best path and routes I/O requests for a specific logical device (PSP defines the path policy).
The correct ESX/ESXi host Storage Array Type Plugin (SATP) to be used is related to the HP 3PAR
array host persona in use. When HP 3PAR host persona 6/Generic-legacy is the host persona
in use with an ESX/ESXi host, the SATP VMW_SATP_DEFAULT_AA should be used. When HP 3PAR
host persona 11/VMware is the host persona in use with an ESX/ESXi host, the SATP
VMW_SATP_ALUA
array host persona in use. When HP 3PAR host persona 6/Generic-legacy is the host persona
in use with an ESX/ESXi host, the SATP VMW_SATP_DEFAULT_AA should be used. When HP 3PAR
host persona 11/VMware is the host persona in use with an ESX/ESXi host, the SATP
VMW_SATP_ALUA
should be used.
For ESX/ESXi 4.0 versions (4.0 GA through all 4.0 updates), the default SATP rules must be edited
in order to automatically achieve a round robin I/O path policy for storage devices.
in order to automatically achieve a round robin I/O path policy for storage devices.
As of ESX/ESXi 4.1, additional custom SATP rules can be created that target SATP/PSP to specific
vendors while leaving the default SATP rules unmodified. The custom SATP can be used to
automatically achieve a round robin I/O path policy for storage devices.
vendors while leaving the default SATP rules unmodified. The custom SATP can be used to
automatically achieve a round robin I/O path policy for storage devices.
Configuring ESX/ESXi Multipathing for Round Robin via SATP PSP
CAUTION:
VMware specifically warns not to directly edit the esx.conf file.
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Configuring the Host for a Fibre Channel Connection