centos 8 guest display corruption

[neuronetv]

I'm running centos 7 with virtualbox-6.1, It's a basic server - command line only machine.
I'm trying to create a centos-8 guest. The installation procedure of the guest goes ok until it gets near the end and then I get this: http://198.91.92.112/centos8-vm.jpg (486kn). tried 3 times now, the first two times using setup option 'server with GUI' and the last option was 'minimal'. I was surprised it even did this on a minimal install. I also tried install using basic display driver, no joy.
I expect I need to maybe include some otpion when creating the vm but i don't know what that is. thanks for any help.

update: image now uploaded

[neuronetv]

bump
anyone?

[multiOS]

As your post has been viewed many times, I'm guessing that there is a reluctance to click on the external link posted to download an unknown file.

If an image is really necessary then I suggest reducing the size the Forum's "Upload Attachment" Tab can accept (128kb) by selecting portion of the screen which identifies the problem/error.

[neuronetv]

thankyou for your advice. I've now uploaded the image as an attachment in my original post

[scottgus1]

Start the guest from full normal shutdown, not save-state. Run until you see the problem happen, then shut down the guest from within the guest OS if possible. If not possible, close the guest from the host command line with the Power Off option set.

Go to the guest's folder and zip these two things:

the guest's .vbox file
the latest vbox.log in the Logs subfolder.

Post the zip file, using the forum's Upload Attachment tab.

[neuronetv]

thankyou for your response.
please note this corruption happens during the installation of centos 8 as a guest. I can go through the initial setup steps ok but it happens towards the end. The blue line fills from left to right (as normal) it gets to about 75% and then the image corrupts. I'm only able to shut the centos 8 guest down by command from the host. I've attached the two files you mentioned as files.zip. In case it's relevant, here are the commands I use in the host to create the centos 8 guest:

VBoxManage createvm --name "centos8" --register
VBoxManage modifyvm "centos8" --memory 1000 --acpi on --boot1 dvd --ostype redhat_64 --nic1 bridged --bridgeadapter1 em1 --vrdeport 3390
VBoxManage createvdi --filename ~/VirtualBox\ VMs/centos8/centos8.vdi --size 10000
VBoxManage storagectl "centos8" --name "IDE Controller" --add ide
VBoxManage storageattach "centos8" --storagectl "IDE Controller" --port 0 --device 0 --type hdd --medium ~/VirtualBox\ VMs/centos8/centos8.vdi
VBoxManage storageattach "centos8" --storagectl "IDE Controller" --port 1 --device 0 --type dvddrive --medium /home/packages/CentOS-8.2.2004-x86_64-dvd1.iso
VBoxHeadless --startvm "centos8" --vrde on &

[scottgus1]

Looks like for some reason the video color depth, or the whole screen, is turning off:

00:12:17.509680 Display::i_handleDisplayResize: uScreenId=0 pvVRAM=0000000000000000 w=1152 h=400 bpp=0 cbLine=0x0 flags=0x0 origin=0,0
00:12:17.577150 VMMDev: SetVideoModeHint: Got a video mode hint (1364x768x0)@(0x0),(1;0) at 0
00:14:02.061545 VRDP: TCP server can't send data.
.....

Try increasing video RAM:

00:00:00.100287 VRamSize <integer> = 0x0000000000800000 (8 388 608, 8 MB)

Give it 32MB as a test.

[neuronetv]

thankyou for your response. I tried increasing the video ram to 32, the image still corrupted. So I then tried increasing it to 128 and it still corrupted.

[scottgus1]

OK, thanks! I don't see anything in the log that looks wrong. Better eyes than mine will have to look.

As a test, I'd try installing this OS on a regular GUI PC and see how it goes. Then try copying the guest's folder to the command-line server and register the guest's .vbox file, see if it boots.

[fth0]

Regarding the VBox.log file, I don't know which messages to expect when the host OS has no GUI, the VirtualBox Manager is not running, and VRDP is used.

If you do another run, please note down the wall clock times for some events you deem important, and provide them together with the VBox.log file.

[multiOS]

I'f I'm reading the log correctly, I think the real problem is in trying to run 2 64-bit Operating Systems with limited resources, i.e. a 2-core i3 processor coupled with just 4 (3.5)GB RAM.

The CentOS site points to RHEL for minimum/maximum system specs, which says that the RAM requirement for an x86/64 system is "1.5GB minimum, 1.5GB per logical CPU recommended" which could just about be afforded if no additional software is running on the Host. I've only ever installed CentOS with a GUI; and the installer wouldn't run at all until the VM was allocated 2 CPUs (= a dual core processor) and 2GB RAM, which seems to be, increasingly, a realistic minimum for 64-bit Linux installations.

[neuronetv]

still the problem persists. I beefed up the guest with the following commands:
$ VBoxManage modifyvm "centos8" --memory 2000
$ VBoxManage modifyvm centos8 --vram 32
$ vboxmanage modifyvm "centos8" --cpus 2
but the display image still corrupts right towards the end on the centos8 guest install.

[neuronetv]

hold on a sec, just had a breakthrough. with the display image corrupting I had assumed that the installation had failed. but I tried booting from the disk this time with the commend:
VBoxManage modifyvm centos8 --boot1 disk
lo and behold centos 8 started up correctly as a guest and I have GUI as well.

[mpack]

Just a guess, but I think VRDP is mirroring the graphics RAM - which is garbage because the guest OS doesn't initialize it - which is not the same as the VM not having any graphics capability.

I don't know if it's even possible to VRDP into a text mode shell - perhaps the "Remote Desktop" part of that acronym ought to be a bit of a clue there. I believe that standard practice would be to run the VM headless, then SSH in. Graphics RAM can be reduced back to whatever the template chose.