Update from 11 to 11.1 causes VNC display disruption and VM mac address change

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I updated to 11.1 from 11 today and experienced the VNC connections both web and client to be garbled and also the mac address changed hence DHCP changed the IP. I am not 100% sure of the mac address change (I couldn't reach the old IP and don't have access to the DHCP server logs) but suspect it from the 'auto generate mac' description when the config for VNC doesn't have one specified, I was expecting it to use the one it chose in 11. The mouse in VNC is an X like old X windows, it's there but all interlaced / garbled multiple duplicated pictures of the windows logo across the VNC terminal. I switched back to 11 and all is normal, same mac address so same IP again. This is a Windows 7 VM. Any other information needed I can post too, was wondering if others experienced this or it is something specific to me. I tried most of the resolution choices for VNC, and all did the same thing in both the web and non-web client.
 

Patrick M. Hausen

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I think those issues aren't the same as mine.

The mac address one may be the issue I am seeing yet it is persistent in 11 and rebooting back into 11 also grabbed the same IP I had previously with 11. It may be that a regression happened in 11.1 vs. 11 in how that mac is autogenerated and now it isn't persistent. If that is the case then it matches my problem.

This bug ticket matches my VM issue with DHCP changing addresses in 11.1 vs. 11
https://redmine.ixsystems.com/issues/27274

VNC connects fine, it just garbles the screen like scrambled satellite channels when the frame size isn't the same as the actual data. The screen / login prompt of Windows 7 repeats over and over with an interlaced look to it (boot up and all). It seems that the issue listed about VNC is where it won't let you connect. I am not sure if it is a Windows 7 VM specific issue, it does it for the initial BIOS bootup of the VM too. I don't see any issues matching the VNC garble screen with Windows 7 problem I have.
 

schoopy

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Hello,
I also did an upgrade from 11.0 U4 and am experiencing same issues: vnc screen is scrambled in viewer as well as on the web vnc viewer. Furthermore the guest system no longer seems to activate its network which is a problem as I have ad server in there!
Could you please explain how you switch back to 11.0U4, I have it in my boot dataset but am not sure if I can simply reactivate it to do the trick without running into further issues.
Thanks
 
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I see this is 'fixed' via having to put a mac manually in the old UI here https://redmine.ixsystems.com/issues/26559. I guess when updating all old VM mac addresses will have to be saved manually by hand to a document and put into the new UI after finding the VMs new IPs via DHCP. For Windows 7 VNC doesn't have a mouse so it is not so 'easy' yet can be done with some effort.

So does anyone else have VNC scrambling with Windows 7 in 11.1? I don't see any more responses here and suspect a bug ticket won't have any secret to reproduce it, I have no idea what is different about my Win7 install and Windows installs seem somewhat variable unfortunately. Is it perhaps a VNC video driver or what would case the messed up display through VNC? Thanks!
 

Patrick M. Hausen

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I noticed the mouse problem over VNC with Windows 7, too - installation is theoretically possible with just a keyboard, so I gave it a try.

After getting random freezes of the VM I gave up and installed Windows 10 Professional instead - works like a charm ;)

And, yes - putting fixed MAC addresses into the VM NIC configuration works as expected. But why do you think an update wouldn't just preserve them?

Patrick
 
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Yes Windows 10 works great, unfortunately I have legacy clients :) For me Windows 7 works very well with remote desktop, initially setup via VNC (When it worked in 11.0).

The current 11.1 state seems to generate a new MAC every reboot of the system from what I read. Then the fix will allow you to input a new one manually or auto-generate one with a button to prevent that behavior. This doesn't seem to say it will auto-generate the one it used for 11.0 which should be saved somewhere since it always comes back with the same MAC in 11.0. So from what I can tell, it will not attempt to retrieve the old MAC in 11.1-U1 and instead auto-generate and save a completely different MAC. Which is a lot of busy / manual work and multiplied times the number of VMs one has to set with the same MAC or reconfigure static DHCP or change all remote desktop clients IPs (and discover the new one from the DHCP server when one might not have admin control of the DHCP server to easily derive them). It is doable but a good amount of work to get back to one was with 11.0 when many VMs are setup with expected MAC addr and IPs allocated to them via DHCP.
 

Patrick M. Hausen

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The current 11.1 state seems to generate a new MAC every reboot of the system from what I read.
Unless you put one in there manually and save.

So the regression is not that it does not persist MAC addresses at all, but rather that it doesn't generate and persist at first boot like it used to and like VMware and Co. have been doing all along ...

Then the fix will allow you to input a new one manually or auto-generate one with a button to prevent that behavior.
Again: you can already do that now - input one manually. Everything will be working from that moment on.

HTH,
Patrick
 
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Note that I just realized how my Linux and Windows VMs had the scrambled screens with VNC (both web and standalone VNC clients). I am surprised only one other person saw this, and now thinking about it I can't see what would cause it only for some people if it ranges across CentOS 7 and Windows 7 VMs (seems like any VM on my system would do it, they all behaved the same). I can see how with resolutions it felt like the VNC clients were trying one resolution and the serving was giving another so the stride aspect was off and it was all shuffled in an interlaced shifted pattern.
 
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Ah I rebooted and found that VNC isn't scrambled. I had tried the web VNC initially and get the feeling that was what scrambled the VNC server somehow. This time I haven't touched the web based VNC viewer yet. I will report if I can recreate the issue again, happy it seems to be working now and may have some way to reproduce the condition I suspect.
 
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I reproduced the issue now and can see it happens which picking some of the resolutions but not others for VNC. It does look like the stride value isn't being set for ones that need that, while some work with 0 and those ones seem to work (saw this in a google search so I am theorizing yet feels most likely the issue going on). 1024x768 always works with my Windows 7 VM, yet choosing 1400x1050 triggers the issue. So that seems to be the bug trigger that I found which should be reproducible by others.

Added this issue for it: https://redmine.ixsystems.com/issues/27758

Update: This isn't Windows 7 specific, Ubuntu does it too.
 
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BlahJohnBlah

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I had the same UI issue, thanks for the list! on 2 different VMs I happened to choose two different resolutions that were both unsupported!! Not sure what the chances of that is?! All good now.
 

QS639X2dq

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So, I was able to have success, after facing the same exact issue, by doing the following:

FreeNAS > Virtual Machines > (debian VM) > Devices > VNC > Uncheck the web GUI checkbox
FreeNAS > Virtual Machines > (debian VM) > Devices > VNC > Set resolution to 800x600
RealVNC > Expert Settings > Scale > 800x600
 
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