libvirtd logon prompt blocklng access to my computer

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tmoble
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libvirtd logon prompt blocklng access to my computer

Post by tmoble »

Hi, all
trying again. Apparently my previous posts were unacceptable here. Mint 19.1, linux kernel 4.15.0-96-generic

I;m unable to logon to my main computer.. after runing an update from the icon near the clock, I rebooted and the system comes up to a libvirtd qemu password prompt/ I don't know why this happened or why. I just need to get my system back. Does anybody know how to stop libvirtd from starting at boot? I have no virtual machines installed at all. I did try one a couple months ago but gave up on it when I couldn't get my logitech keyboard to work.

any bright ideas? I'm on the machine now, booted into recovery mode, single user root mode.
powerhouse
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Re: libvirtd logon prompt blocklng access to my computer

Post by powerhouse »

You could uninstall Libvirt if you don't run virtual machines.

Before trying to uninstall, stop and deactivate libvirtd. I think its:

systemctl stop libvirtd.service

followed by

systemctl disable libvirtd.service

but I've been hopping distros so I might be wrong with the syntax.
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tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

>>>booted into recovery mode, single user root mode.

logged on this way it won't bring up software manager. I tried doing it with apt but apparently couldn't get the correct name of the package. I tried various means of searching for the package name but got nowhere. I understand about stopping the service but it will come back on next boot, right?

Thanks for taking time to respond.
tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

ok, used apt-cache to find the names of libvirtd packages. went thru the list and ran apt-get remove on several. got burned out on it and ran ran apt-get remove libvirt* which resulted in a lot of action. So, rebooted as normal but still get the screen with the libvirtd qmenu logon prompt.

anybody have any idea what is generating this? Something in one of the /etc/rc scripts?something in systemd? I have no idea about systemd at all. can it be administered from a root prompt?
ajgringo619
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Re: libvirtd logon prompt blocklng access to my computer

Post by ajgringo619 »

Did you ever remove qemu after you were done? I've used it many times, but was never prompted for a password unless I was actually running a VM. Try running apt purge qemu; that should get rid of libvirt as well (if not, you'll probably be prompted to run sudo apt autoremove).
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tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

algringo619, thank you for taking time to post. I was really glad to see that suggestion, it looked to be really to the point. however, running the apt command given resulted with this:

root@mint-19:~# apt purge qemu
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package 'qemu' is not installed, so not removed
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

Soi, I still don't understand where the command that generates the prompt is coming from. A further possible clue is this response from the systemctl command given above:

root@mint-19:~# systemctl disable service libvirtd
Unit /etc/systemd/system/libvirtd.service is masked, ignoring.

This would seem to imply that the system is running off systemd, not the sysv init stuff I'm familiar with. knowing nothing of systemd I looked around and found this:

https://blog.ruanbekker.com/blog/2017/1 ... n-systemd/

but I was unable to find a libvirtd file in /etc/systemd or in /etc/systemd/system

any bright ideas, pithy remarks or dumb looks are welcome. :)
ajgringo619
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Re: libvirtd logon prompt blocklng access to my computer

Post by ajgringo619 »

Can you post a picture of the login screen? Something isn't making sense here.
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tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

I can, it'll take a few mins what with rebooting a few times and whatnot.
tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

here's what it looks like. that background with the dots is different foo. my usual screen has the overlapping slabs look.

cripes, it won't let me upload the pic. sez it's too big, it's 3.3MB.

I'll try to upload it to my imgur and link it from there.
tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

https://imgur.com/Ni8Jb2T

I think this is it anyway
ajgringo619
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Re: libvirtd logon prompt blocklng access to my computer

Post by ajgringo619 »

Try clicking on "Tom" and entering your password. For some reason, the libvirtd user ID that qemu created is still active, although why it's in the login window makes no sense.

What does grep libvirt /etc/passwd return?
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tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

grep libvirt /etc/passwd
libvirt-qemu:x:64055:128:Libvirt Qemu,,,:/var/lib/libvirt:/usr/sbin/nologin
libvirt-dnsmasq:x:122:131:Libvirt Dnsmasq,,,:/var/lib/libvirt/dnsmasq:/usr/sbin/nologin

nologin? what does that mean?
tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

those red x's are lower case and white on my screen.

I'll try your other suggestion now. it involves a couple reboots
ajgringo619
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Re: libvirtd logon prompt blocklng access to my computer

Post by ajgringo619 »

Please post the results of these:

Code: Select all

apt search libvirt | grep ^i
apt search virt-manager | grep ^i
Mint 19.3 XFCE [kernel 5.4.0-51-generic]
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tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

HAH!! Success, at least superficially. When I clicked on my name it moved to a spot just above the password entry box. I entered the last password I had reset it to in the root screen, no good. Then I tried the password I had before all this junk started, it bought into it and logged me on. Also got the old overlapping slabs looking desktop background back. OMG, ajgringo619 has rescued me from a fate worse than death. Thank you aj. Now I'm wondering if it would have worked earlier. I never thought to do it because it didn't appear clickable. WOW, my bacon is saved. ajgringo, you ever in the Phx area? beers will be bought and served if so. I just did a donation to the forum, I'll do another.

Shall I hold my breath and reboot again? I only boot this thing like quarterly except the 17 or so in the last couple days. A huge weight has lifted off my shoulders. at least it feels like that.
ajgringo619
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Re: libvirtd logon prompt blocklng access to my computer

Post by ajgringo619 »

After you post the results of the commands I gave you, we can then get rid of the libvirtd stuff once and for all. Both of the usernames in your /etc/passwd were used by qemu when creating/running VMs. It's a great system, way faster than VirtualBox IMHO and without the constant new kernel build issues.

We're almost there! (I might make a trip to Peoria next spring for baseball, if the jackasses can figure out how to start playing again.)
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tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

and here you go:

tom@mint-19:~$ sudo apt search libvirt | grep ^i
[sudo] password for tom:
tom@mint-19:~$
and

tom@mint-19:~$ apt search virt-manager | grep ^i
E: Error saving configuration file - apt_dumpcfg (13: Permission denied)
E: Error saving configuration file - apt_dumpcfg (13: Permission denied)
tom@mint-19:~$

but I didn't sudo it, try again.... OK, nothing found
tom@mint-19:~$ sudo apt search virt-manager | grep ^i
tom@mint-19:~$

I has already removed the pkgs with apt-get remove.... so no big surprise.
ajgringo619
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Re: libvirtd logon prompt blocklng access to my computer

Post by ajgringo619 »

Interesting. You should not have needed to use sudo to run any of those commands. You should now be able to delete those extraneous users, but I'm concerned with the permissions errors you received doing a simple search of the apt database.

For now, just remove those libvirt users:

Code: Select all

sudo userdel libvirt-qemu
sudo userdel libvirt-dnsmasq
The /usr/sbin/nologin means that the user account cannot login directly, but it can still run processes.
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tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

there was only one user libvirtd-qemu. he's gone now, my id is the only one in usermanager.

I'm going to try a reboot now, see if it stays fixed.

Did I mention Thank You for your time and trouble answering?
tmoble
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Re: libvirtd logon prompt blocklng access to my computer

Post by tmoble »

It came up OK thanks to you. Guess I'm going to have to study up on VMs before trying again.
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