CAUTION: The procedure for changing the default SATP rules to use the round robin I/O multipathing policy is intended to apply only to VMware hosts using HP 3PAR StoreServ Storage LUNs. If the host is sharing storage from other vendors, then before making any I/O policy changes, consideration should be given to the effect that changing the default rules will have on the storage environment as a whole.

A change of the default PSP for a given SATP affects all storage devices (FC, FCoE, iSCSI) that use the same default SATP rule. If a host is sharing multiple storage vendors together with an HP 3PAR StoreServ Storage, and if the other connected storage does not support active/active round robin multipathing using the same SATP rule, such as VMW_SATP_DEFAULT_AA or VMW_DEFAULT_ALUA, then its multipathing will be also be affected.

If the other storage uses a different SATP of its own, then SATP VMW_SATP_DEFAULT_AA mapping should be changed to VMW_PSP_RR to take advantage of round-robin multipathing. You can check the SATP-PSP relationship of a given device for ESX 4.0 by using the esxcli nmp device list or esxcli nmp device list -d <device id> command.

For example, If the HP 3PAR StoreServ Storage and storage X are connected to the same host using VMW_SATP_DEFAULT_AA, and if storage X does not have its own SATP, then it might cause an issue if storage X does not support round-robin multipathing. If the HP 3PAR StoreServ Storage and storage Y are sharing the same host, and if storage Y has its own SATP VMW_SATP_Y and HP uses VMW_SATP_DEFAULT_AA, then there will be no conflict, and the change can be made.

ESX/ESXi 4.1 GA - 4.1 Ux

HP 3PAR custom SATP rule for use with persona 6/Generic-legacy (Active-Active array port presentation)

#esxcli nmp satp addrule -s "VMW_SATP_DEFAULT_AA" -P "VMW_PSP_RR" -O iops=100 -c "tpgs_off" -V "3PARdata" -M "VV" -e "HP 3PAR Custom iSCSI/FC/FCoE Rule"

To remove the above active-active custom SATP rule:

#esxcli nmp satp deleterule -s "VMW_SATP_DEFAULT_AA" -P "VMW_PSP_RR" -O iops=100 -c "tpgs_off" -V "3PARdata" -M "VV" -e "HP 3PAR Custom iSCSI/FC/FCoE Rule"

HP 3PAR custom SATP rule for use with persona 11/VMware (ALUA compliant array port presentation)

#esxcli nmp satp addrule -s "VMW_SATP_ALUA" -P "VMW_PSP_RR" -O iops=100 -c "tpgs_on" -V "3PARdata" -M "VV" -e "HP 3PAR Custom iSCSI/FC/FCoE ALUA Rule"

To remove the above ALUA custom SATP rule:

#esxcli nmp satp deleterule -s "VMW_SATP_ALUA" -P "VMW_PSP_RR" -O iops=100 -c "tpgs_on" -V "3PARdata" -M "VV" -e "HP 3PAR Custom iSCSI/FC/FCoE ALUA Rule"

ESXi 5.x

HP 3PAR custom SATP rule for use with persona 6/Generic-legacy (Active-Active array port presentation)

#esxcli storage nmp satp rule add -s "VMW_SATP_DEFAULT_AA" -P "VMW_PSP_RR" -O iops=100 –c "tpgs_off" -V "3PARdata" -M "VV" -e "HP 3PAR Custom iSCSI/FC/FCoE Rule"

Multipath Failover Considerations and I/O Load Balancing 43

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HP QR516B manual ESX/ESXi 4.1 GA 4.1 Ux