Blank Screen

I was watching a movie Saturday night. When it finished, I went to log off my ProBook, but it said there was a task running and I needed to input my password, which I did. It has never done this before. When I went to use it yesterday, it posted, but after that I just get a blank screen, but no it can't find a boot device. I presume it's trying to boot, but is somehow corrupted. I got to the recovery mode by holding down the shift key during boot, but am not sure what to do next. Is there some way I can fix this so I don't have to re-install? Thanks for any help.

 

Hrm, are you booting via EFI or regular MBR? If it's EFI, you may just need to fiddle with the BIOS settings and re-add an entry for your linuxes.

If it's not that.. What distro were you running? The next step would be to boot a rescue image via USB and restore your bootloader. Different distros have different ways of doing it, but if you're going in manual with a crowbar you'd do something like:

Boot a live image and open a root terminal (or regular terminal and sudo su).

Mount your root partition at /mnt (where sdX is the partition such as /dev/sda1, etc):

Code:

mount /dev/sdX /mnt

Mount your boot partition (if using a separate one):

Code:

mount /dev/sdX /mnt/boot

Mount your EFI partition (if using EFI):

Code:

mount /dev/sdX /mnt/boot/efi

Bind mount stuff for later use via chroot:

Code:

for x in proc sys dev; do mount -o bind /$x /mnt/$x; done

Chroot to your root partition:

Code:

chroot /mnt

Re-install grub (let's assume /dev/sda):

Code:

grub-install /dev/sda

If it craps out here you may have forgotten to mount something above (or mounted the wrong partition), or tried to install to the wrong device... or booted in the wrong mode (either via EFI with an MBR installation, or via MBR on an EFI installation). Try again but boot in the other mode from the one you just tried. This may require different boot media for some distros, or for distros that provide hybrid media you may need to manually select the BIOS boot menu and select the specific mode from the BIOS boot menu.

If this step fails and you can't get past it with that advice, just post the error message.

Update grub:

Code:

update-grub

Then give it the old reboot. If it's losing your settings after a reboot you may have a problem with your boot order or you may have a system that has a crap EFI implementation and you're just figuring that out now. The way around that is to move the target .efi file to the root of the EFI partition and and rename it to bootx64.efi. Some BIOS implementations have this somewhat hard-coded and that's one way to get them booting.

 

I forgot to mention, there's also another way to do this to just get straight to your existing installation, and then reinstall grub from there. Boot anything that can get you to a grub> prompt (most live images have a key you can hit to get to a grub boot prompt) and then do something like this:

Code:

insmod ext2
set root='(hd0,1)'
linux /vmlinuz-whatever-hit-tab-to-autocomplete root=/dev/sdX ro
initrd /initrd.img-whatever-hit-tab-to-autocomplete
boot

...where hd0,1 is your boot partition and sdX is your root partition (like /dev/sda2). You can type just ls at the prompt or while typing hd(something) hit tab to see available devices/partitions, and type ls (device/partition) to see what's on a particular device as long as it's formatted ext. Make sure that your vmlinuz and initrd versions are the same if you have multiple kernel versions installed (you might).

After you boot just do grub-install /sdX and update-grub. If those fail the same caveats apply as above, post the error message(s) and take it from there.

 

Thanks for the reply. I'm just running Ubuntu 20.04, which I thought would be a good choice as it's a LTS version. I've had the current iteration on there for at least three months. I did see where people were having the blank screen, but that was upon installation, not after months of trouble free use. Having to use my password to shut down was very odd. I'll take a look at this over the weekend. I was thinking about tossing Windows 10 on there to see if I can find a version of that I like so I can upgrade my main desktop to Windows 10, then go back to it later. Thanks again.

 

Wait, are you failing to boot, or do you have a blank screen after booting?

If you're seriously going to just install windoze I won't waste my time trying to help further. What a troll

 

No it posts, so I can go into the BIOS and make changes, but after that when the Ubuntu logo usually comes on screen is when I get the blank screen. I did install Win10 today, but hopefully that'll be short and sweet so I can come back.

 

I had this exact issue and I figured out it was missing shim-signed package for EFI boot. I had AIOBoot with REFInd bootloader which booted my dead Linux machine w/o any fuss and I opened Synaptic or terminal to install shim-signed packages and it also grabbed efibootmgr, grub-efi-amd64 as well and voila! I have a working bootloader. Run sudo update-grub in terminal before restarting.
Most 20.04 have this issue. I think it will be fixed in July/August Point release.

 

My guess is that you got prompted for a system update and then something went awry on a reboot. What we would need to figure out is if the kernel is actually booting, or if you're stuck at the bootloader. @Vasudev I didn't even consider secure boot part of the equation! That's a good thing to check as well.

I haven't booted 20.04 yet, but there should be a key combo you can use to escape the boot splash, I think maybe ESC? That would at least tell you that your kernel is starting to boot and give some possible error messages.

 

This decision by linux to have just the logo annoys me to no end. After I install, I set it up so that I actually see what is happening during boot. AFAIR it's just a parameter entry in grub.

 

I think it was a nice move otherwise plymouth-boot screen will be stuck for a minute even on NVMe drive. Ubuntu 20.04 or similar distros have this changes. Only thing you can do is to increase boot timeout values and un-hide Grub2-efi by editing grub2 file.

 

GRUB_DEFAULT=0
GRUB_TIMEOUT_STYLE=hidden
GRUB_TIMEOUT=0
GRUB_DISTRIBUTOR=`lsb_release -i -s 2> /dev/null || echo Debian`
GRUB_CMDLINE_LINUX_DEFAULT="quiet ipv6.disable=1"
GRUB_CMDLINE_LINUX="ipv6.disable=1"

The line to remove the splash is the word splash in the DEFAULT line, quiet just lets the boot processes load in the background w/o cluttering the screen. If anything hangs it appears on screen still.

 

With splash if you get horizontal or vertical lines whilst booting on nvidia dGPU you can easily switch to nvidia optimized or iGPU only in recovery. With Intel only or Amd only iGPU splash screen consumes 1-5secs at the max.
You can tweak further by using systemd-analyze blame. Usual suspects for longer boot time include network.wait.services and apt.service which can be safely disabled at startup and switch to on-demand start. You can also do the same if you're using postgres, mysqld, mariadb, redis etc..