What is Satp in VMware?

Storage Array Type Plug-in (SATP) List. Storage Array Type Plug-Ins (SATPs) to the VMware Pluggable Storage Architecture multipathing solution for the specific characteristics of the storage array.

What is alua configuration?

Asymmetric logical unit access (ALUA) is supported for certain combinations of host operating systems and host multipathing software. ALUA is an industry standard protocol for identifying optimized paths between a storage system and a host computer.

What is SATP storage?

vSphere Pluggable Storage Architecture (PSA) Figure 5.2 depicts the relationship between SATP and NMP. Figure 5.2. SATP. SATPs are PSA plug-ins specific to certain storage arrays or storage array families. Some are generic for certain array classes—for example, Active/Passive, Active/Active, or ALUA-capable arrays.

What is alua in Vnx?

Support has been added for Asymmetric Logical Unit Access (ALUA) with CLARiiON and VNX arrays. By default, support for ALUA is enabled in ONTAP. But to use it, ALUA must be enabled on the storage array. You should enable ALUA only on new configurations. You should not enable ALUA in an existing configuration.

What is multipath alua?

ALUA definition: Asymmetric Logical Unit Access (ALUA) is a multi-target port access model. In a multipathing state, the ALUA model provides a way of presenting active/passive LUNs to a host and offers a port status switching interface to switch over the working controller.

Where is LUN in Vcenter?

  1. In vSphere, select the host configuration tab, storage.
  2. Select the Devices View.
  3. Sort by LUN # and locate the LUN you want to verify.
  4. Right click the LUN in the Devices list and select “Copy identifier to clipboard”
  5. Copy the converted string and paste to a work note.

What is a target port group?

A target port group is defined as a set of target ports that are in the same target port asymmetric access state at all times. A target port group asymmetric access state is defined as the target port asymmetric access state common to the set of target ports in a target port group.

What is RTPG in Alua SATP?

A TPG is defined as a set of target ports that are in the same target port asymmetric access state at all times. The ALUA SATP plugin sends RTPG (Relative Target Port Group) commands to the array to get the device server’s TPG identifiers and states.

What is alua and how does it work?

It allows access to the array devices via both SPs but clearly identifies to the initiators which targets are on the owner SP and which are on the non-owner SP. ALUA support was first introduced in vSphere 4.0.

What is the history of ALUA support?

ALUA support was first introduced in vSphere 4.0. ALUA is described in the T10 SCSI-3 specification SPC-3, section 5.8 (see www.t10.org/cgi-bin/ac.pl?t=f&f=spc3r23.pdf; access to this URL requires T10 membership or other organizational access). The official description from this standard is as follows:

What is implicit ALUA and how to configure it?

This is not configurable by the way, as it is an attirbute of the device. In implicit ALUA, a device’s TPG state will be managed by the target device itself. This is not configurable either, as again it is an attirbute of the device. ALUA is typically associated with Asymmetrical Active-Active (what we will term AAA) arrays.