User guide

Technical white paper | HP Enterprise Virtual Array Storage and VMware vSphere 4.x and 5.x configuration best practices
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When a path failure occurs, the NMP communicates with the SATP and PSP and then takes the appropriate action. For
example, the NMP would update its list of available paths and communicate with the PSP to determine how I/O should be
re-routed based on the specified path selection policy.
Displaying the SATP list
Although there is no way to monitor the NPM’s list of available paths through vCenter, you are able to display a list of
available SATPs and their respective default PSPs (as shown in Table 5).
Use the following CLI command on the ESX console:
esxcli nmp satp list/grep EVA
Note
Currently, you cannot reconfigure the SATP rules table through vCenter.
Table 5. vSphere 4.x and 5.x SATP rules table, with entries that are relevant to EVA arrays denoted by an asterisk
SATP
Default PSP
Description
VMW_SATP_ALUA_CX
VMW_PSP_FIXED
Supports EMC CLARiiON CX arrays that use ALUA
VMW_SATP_SVC
VMW_PSP_FIXED
Supports IBM SAN Volume Controller (SVC) appliances
VMW_SATP_MSA
VMW_PSP_MRU
Supports HP Modular Smart Array (MSA) arrays
VMW_SATP_EQL
VMW_PSP_FIXED
Supports EqualLogic arrays
VMW_SATP_INV
VMW_PSP_FIXED
Supports the EMC Invista application
VMW_SATP_SYMM
VMW_PSP_FIXED
Supports EMC Symmetrix arrays
VMW_SATP_LSI
VMW_PSP_MRU
Supports LSI and other arrays compatible with the SIS 6.10 in non-AVT
mode
VMW_SATP_EVA*
VMW_PSP_FIXED
Supports HP EVA arrays
VMW_SATP_DEFAULT_AP*
VMW_PSP_MRU
Supports non-specific active/passive arrays
VMW_SATP_CX
VMW_PSP_MRU
Supports EMC CLARiiON CX arrays that do not use ALUA protocol
VMW_SATP_ALUA*
VMW_PSP_MRU
Supports non-specific arrays that use the ALUA protocol
VMW_SATP_DEFAULT_AA
VMW_PSP_FIXED
Supports non-specific active/active arrays
VMW_SATP_LOCAL
VMW_PSP_FIXED
Supports direct-attached devices
IMPORTANT
SATPs are global, whereas a PSP can either be global or set on a per-Vdisk basis. Thus, a particular array can only use a
specific SATP; however, Vdisks on this array may be using multiple PSPs – for example, one Vdisk can be set to round robin
I/O path policy, while another Vdisk on the same array is set to MRU.
As indicated in Table 5, the following SATPs are relevant to EVA arrays:
• VMW_SATP_DEFAULT_AP – This SATP is used by active/passive EVA arrays. However, since such arrays are not supported
in vSphere 4.x and 5.x, you should not use this plug-in to enable a vSphere 4.x and 5.x connection to an active/passive
EVA for production purposes.
• VMW_SATP_EVA – This SATP is intended for active/active EVA arrays that have the Target Port Group Support (ALUA
compliance) option turned off; however, all such arrays have TPGS turned on by default. Since this option is not user-
configurable, no current EVA arrays use VMW_SATP_EVA.
• VMW_SATP_ALUA – This SATP is intended for any ALUA-compliant array; thus, it is used with active-active EVA arrays.