iScsi and Globalsan problem

[TimThaler]

Hi there,
I have a Mac Mini server running under Sierra. Latest GlobalSAN iSCSI initiator is installed (5.3.1.555). The target is a QNAP TS-659 with FW 4.2.6. I created 2 targets (backup and files), no ACLs.
Connection usually works fine. Sometimes I get an error window telling me that either files or backup was not disconnected properly.
So I created a ticket with SNS support and they tried to find the error. They say it's not related to GlobalSAN but to the QNAP box.
Before I updated my Mac Mini it ran under 10.9 with the Xtend SAN software. I never had any issues with that combination. They asked for the full price for an update so I went with GlobalSAN which is way cheaper...
Is anybody else using GlobalSAN with a Qnap box? If so are there any problems?
I started the iSCSI logging on the Qnap box and I get inormation only (no errors). Strangely the targets logout and back in a few times every day. Are these logouts/logins initiated by the Qnap? Why is that? The GlobalSAN support says that they never logout the device from their software. If the Qnap logs out after a while for some reason, probably the GlobalSAN logs back in after a short time. Sometimes the time gap is short (see yourself in the log), sometimes it takes longer. Maybe the OS detects the login before the GlobalSAN app, so that I sometimes get the disconnection error message.
If so, is there a way to prevent the Qnap from automatically logging out after some idle time?

Thanks for your support, Tim

[storageman]

Do you have a block or file LUN (in volume)?
Use block LUN.

[TimThaler]

Thanks storageman for the advice.
I did reinstall the iscsi luns using instant alloction (witch is block access I think). And I did re-enable the HD sleep function in the Qnap box. I did not get a GLO warning from the Globalsan software yet, which is a good sign. But I do still get disconnecting errors on my server, because of some weird behavior of the Qnap. It automatically logs out the iscsi user after some time and the re-login from the Globalsan app sometimes takes too long, so that OSX detects a hard disconnect. E.g. the server complains that there was a disconnet on the 20th @ 3:36am. The access-log say that @ 3:35:56 the backup luns was logged out. @ 3:36:12 the iscsi app logged in again and re-established the connection. For 16s the volume was inaccessible, so that OSX declared it as ejected.
Usually this behavior happens during idle times (the reason for the auto logout I think), so there is no harm done to the data. But it still ** that it happens at all...

So has anybody an idea to prevent the Qnap from automatically logging off the iscsi user after some idle time?

thx for your ideas, Tim

[storageman]

You sure it's the Qnap and not GlobalSAN.
https://studionetworksolutions.zendesk. ... m-Synology
If you temporarily connect to a windows box does it disconnect? (Disconnect Globalsan first)

[TimThaler]

I will check that tonight. I did de-activate the hd-sleep function for some time, but still had the log-offs. So I think that is not connected to the hd-sleep then.
The Globalsan support has told me that their app never logs-off the devices (only if you manually do that or the system shuts down). So what else could it be if not the Qnap?

[TimThaler]

Is there some kind of 'keep-alive' packet that the app could send to delay the auto-log-off from the Qnap?

[storageman]

I will check that tonight. I did de-activate the hd-sleep function for some time, but still had the log-offs. So I think that is not connected to the hd-sleep then.
The Globalsan support has told me that their app never logs-off the devices (only if you manually do that or the system shuts down). So what else could it be if not the Qnap?

Yes, they would say that!

What about trying ATTO Xtend SAN?

[TimThaler]

I used Atto for several years with no problems. When I updated from 10.10 to 10.13 they did not offer an update price for the 4.x version, they asked for the full price. I did not like that behavior and I think the app is too expensive. So I went with Globalsan...

[storageman]

Out of ideas.
You could try a constant ping to the iSCSI address -t or create a batch file with a loop to try and keep the connection alive.

[TimThaler]

Ok, I've tried both Windows 8.1 and my old Atto XtendSAN in Pralells VMs (each for one night). When using these there are no log-outs in the Qnap log. They must do someting different to the GlobalSAN app...
And sorry, it's obviously not the QNap box.
I'll have to talk to the GlobalSAN support again...
Thx for the support.