The opposite is true for TPG thereupon is, it is AO to own LUN dos and you may ANO to possess LUN step 1.
For the certain energetic/couch potato ALUA-capable arrays, you are able to pick port organizations that have “Standby” AAS instead of “ANO” towards the low-manager SP.
Ports in an ALUA TPG can be in the same AAS at all times with respect to a given LUN. The TPG’s AAS are reported to the initiators in response to the Report TPGS command. The TPG descriptor is reported in byte 1 of that response.
Transitioning-The latest TPG AAS is in the procedure for modifying from 1 condition to some other. For example, when your SP regarding a keen AO TPG has been rebooted otherwise are taken offline, or if perhaps the newest SAN (space for storing system) administrator by hand transmits LUN control (into EMC CLARiiON, this will be also known as trespass), new AAS of TPG on solution SP change in order to AO. Although this processes is lingering, the fresh new TPG AAS is transitioning.
While the TPG is in this state, receiving requests from the initiators return Active or a Check Status with sense key Perhaps not Ready and ASC (additional sense code) Analytical Equipment Perhaps not Available or ASYMMETRIC Availability Condition Changeover.
Standby-This state is similar to a passive SP in a non-ALUA configuration and on certain ALUA-capable arrays. It returns a See Condition with sense key Perhaps not In a position.
In the event the TPG is within it AAS, it supports an effective subset out-of purchases so it accepts whether it is during AO AAS:
Unavailable-It AAS might be viewed if the TPG’s use of the brand new LUN is limited as a result of gear problems or other SCSI unit restrictions. A great TPG within county is unable to changeover so you can AO otherwise ANO through to the error subsides.
ESXi six delivers the I/O so you’re able to TPGs that will be from inside the AO AAS, however if they are certainly not readily available, I/O is sent so you’re able to TPGs that are during the ANO AAS. If for example the shop variety gets sustained We/O toward TPGs that are in the ANO AAS, this new selection changes the fresh TPG’s state to AO AAS. Just who helps make one to alter relies on the fresh new ALUA administration function out-of the newest shops variety (understand the second area).
This is accomplished thru a collection of requests and you can responses to help you and you will regarding the stores arrays. This type of orders are as follows:
Query-According to SPC-3, section 6.4.2, in response to this command, an array returns certain pages of the VPD (vital product data) or EVPD (extended vital product data). The inquiry data returned in response to this command includes the TPGS field. If the returned value in that field is nonzero, that device (LUN) supports ALUA. Anchorage AK chicas escort (See Table 6.3, later in this chapter, for the correlation between the value of the TPGS field and AAS management modes.)
Put Target Vent Organizations (Set TPGs)-This command requests that the storage array set the AAS of all ports in specified TPGs. For example, a TPG’s AAS can transition from ANO to AO via the Place TPGs command.
Not Supported-The response to the Report TPGs and Lay TPGs commands is invalid. This means that the storage array does not support ALUA or, in the case of EMC CLARiiON, the initiator records are not configured in a mode that supports ALUA.
Implicit-The array responds to Report TPGs but not Set TPGs commands. In this case, setting the TPG’s AAS is done only by the storage array.
Explicit-The array responds to both Report TPGs and Put TPGs commands. In this case, setting the TPG’s AAS can be done only by the initiator.