How to disable ALUA/TPGS?

[sebastianf]

Hello,

We have some IOT devices which are currently writing data to Microsoft iSCSI target and are searching for a good alternative and stumbled across your great product here.

I already fixed one problem by setting IscsiDiscoveryListInterface value=1 in the cfg file, but there seems to be a second problem.

I'm using a StarWind iSCSI target in a single-controller, non-HA setup (basically a single windows machine). I've encountered an issue where our iSCSI initiator fails to discover LUNs on the target, even though other initiators (like Microsoft's) work fine.

After analyzing packet captures, I've identified the root cause: the initiator's TPGS (Target Port Group Support) multipath discovery logic requires the "Preferred" bit to be set in the REPORT TARGET PORT GROUPS response. StarWind reports TPGS as supported with ALUA (Asymmetric Logical Unit Access) enabled, but doesn't set the Preferred bit in its response, causing the initiator to filter out all LUNs.

Since my setup is single-controller without HA/multipath redundancy, I don't need ALUA/TPGS support at all. Disabling it would make the initiator skip this filtering logic and discover LUNs normally. Unfortunately we cannot change the code of our initiator easily, as many legacy devices are already out there and updating all of them would be a huge effort.

It would be great if you could help me with this problem, especially:
1. How can I disable ALUA/TPGS on a StarWind iSCSI target device?
2. Is there a configuration option in the StarWind Management Console or config file to turn off ALUA, even for existing targets?
3. Alternatively, is there a way to configure StarWind to set the Preferred bit in REPORT TARGET PORT GROUPS responses for single-controller setups?

Any guidance would be appreciated.

Thanks, Sebastian

[yaroslav (staff)]

1. How can I disable ALUA/TPGS on a StarWind iSCSI target device?

While creating the ALUA device, you can toggle that parameter.

2. Is there a configuration option in the StarWind Management Console or config file to turn off ALUA, even for existing targets?

If you are using the TRIAL option (i.e., have access to the GUI and can change settings for the StarWind devices), please reach out back to the person who shared the key with you.
You can change ALUA in the Windows-based StarWind Management Console.
ALUA settings are changed only for HA devices I believe.

Good luck with your project!

[sebastianf]

Hi Yaroslav,

thank you very much, we will try exactly what you proposed!

[yaroslav (staff)]

Good luck with your project!
I've checked the script, and yes, sadly, ALUA is a feature of a HA device. If there are multiple paths, could you please see if there is any MPIO on the client side?

[sebastianf]

Hi Yaroslaf,

Unfortunately my colleague couldn't find an option in the GUI to toggle this. I asked him to create an account and show us some screenshots here.

Our initiator is something written by our company, it doesn't support MPIO and for us it is fine, if the machine goes offline, then we just switch to a different one.

For customers which really want to ensure that data is available, we have a more expensive solution.

We just simply need an windows iscsi target which we can use to record on, not more. Ah and we have chap support.

[yaroslav (staff)]

I've checked the script, and yes, sadly, ALUA is a feature of a HA device. If there are multiple paths, could you please see if there is any MPIO on the client side?

That's why I guess you don't see the button. Your devices are standalone. As a workaround, you can create standalone HAs.
If your StarWind Management console is clickable, reach out to the person who provided you with the key; your system is eligible for some sort of support.

it doesn't support MPIO and for us it is fine, if the machine goes offline, then we just switch to a different one.

Are you referring to the storage machine?
I see, so it is active-passive replication of some sort.

[FilipeMartins]

Hi Yaroslaf,
My name is Filipe Martins, I'm colleague of Sebastian.

I'm attaching some screenshots of the Starwind VSAN free V8.0.20086 installed with Management Console.

Thanks a lot for your support.
Filipe

[FilipeMartins]

Now more tree screenshots because there is a limit to upload.

Please find attached.

Filipe

[yaroslav (staff)]

Nice to meet you & welcome to StarWind Forum.
ALUA settings are normally under the HAimage settings. They are not quite applicable to your case because ALUA settings are a feature of StarWind HA devices while you use non-replicated ones.
Quick question, so I can help you better. If you can access the replication wizard from the UI, you can get some support (my colleague will bring you in contact with the team). If the replication node interfaces are inaccessible, well, you are "stuck" with me here
What you can try is
1. Create a test device and set it as an HA device.
2. Disable ALUA.
3. Remove replication partner; no need to wait for replication to complete.
4. Try again.

p.s. I've deleted the line with my colleague's name.