Add custom SATP claimrule for HP 3PAR to VMware ESXi

This posting is ~5 years years old. You should keep this in mind. IT is a short living business. This information might be outdated.

One of the tasks that I finish before I present the first Virtual Volumes (VV) to hosts is to discuss the need of a custom SATP claimrule with the customer. Requirement for a custom claimrule is usually, that the active and optimized path should be switched after each IO and not after 1000 IOs. Duncan Epping wrote a nice blog post some years ago. I recommend to read it.

Some basics

The Storage Array Type Plug-In (SATP) is responsable for array-specific operations, like health monitoring of physical paths, reporting of path state changes and path failover. Each SATP is linked to a Path Selection Policy (PSP), which controls the selection of active paths for IO. VMware ESXi provides a couple of SATPs:

Claimrules are used to select a valid SATP for a storage system. When a SATP for a given device is searched, the Native Multipathing Provider (NMP) searches the SATP driver part of the rules first. If there is no match, then the SATP vendor/ model part, and finally the SATP transport part is searched. If there is still no match, a valid default SATP rule is selected. And because of this, a custom SATP claimrule is selected instead the default SATP claimrule, because it’s more specific for a given device. The selected SATP determines the PSP.

Adding a custom SATP claimrume

I show you how to add a custom claimrume, in this case for a HP 3PAR storage system. This is an excerpt of some default SATP claimrules.

Usually the highlighted claimrule will cause, that VMW_SATP_ALUA is used for a HP 3PAR storage system, if the ESX hosts use host persona 11 (VMware). For hosts with host persona 6 the VMW_SATP_DEFAULT_AA is used. Please note, that host persona 6 isn’t supported for ESX hosts with 3PAR OS 3.1.3! Since 3PAR OS 3.1.2 you should use host persona 11 instead of 6.

With esxcli you can add a new custom rule:

The switch -s adds a rule for VMW_SATP_ALUA, -P sets VMW_PSP_RR as the default PSP for this rule, -O enables that an active path is switches after 1 IO (default is 1000), -c enables ALUA target port group support, -V is a valid string from the vendor part of the SCSI inquiry string, -M is a valid string from the model part of the SCSI inquiry string and -e is for a description.

If you have to add this rule to multiple hosts, you may want to use these lines of PowerCLI code (make sure that you adjust the $esxCluster variable):

You should add this rule before you present the first VVs to the hosts.

And there it is. Now you can present VVs to your ESX hosts and you can be sure, that this rule is claimed. If you add this rule after you have presented VVs to the ESX hosts, you have to reboot the hosts.

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Patrick Terlisten

vcloudnine.de is the personal blog of Patrick Terlisten. Patrick has a strong focus on virtualization & cloud solutions, but also storage, networking, and IT infrastructure in general. He is a fan of Lean Management and agile methods, and practices continuous improvement whereever it is possible.

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2 thoughts on “Add custom SATP claimrule for HP 3PAR to VMware ESXi

  1. Markus Kraus

    Great Article, thanks for sharing!

    I rewrote your PowerCLI to ESXCLIv2:

    $esxcli2 = Get-ESXCLI -VMHost $ESXiHost -V2
    $arguments = $esxcli2.storage.nmp.satp.rule.add.CreateArgs()
    $arguments.satp = “VMW_SATP_ALUA”
    $arguments.psp = “VMW_PSP_RR”
    $arguments.pspoption = “iops=100”
    $arguments.claimoption = “tpgs_on”
    $arguments.vendor = “3PARdata”
    $arguments.model = “VV”
    $arguments.description = “HP 3PAR custom SATP Claimrule”
    try {
    $esxcli2.storage.nmp.satp.rule.add.Invoke($arguments)
    }
    catch {
    Write-Warning “Error during Configure HP 3PAR SATP/PSP Rule. See latest errors…”
    }

    Reply

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