# Ubuntu – Gnome shell crashes intermittently, sends me back to login

crashgnome

I have an ubuntu 18 04 (updated to 20 04 1 LTS while trying to fix issue) in virtualbox, and it started to crash since today, i think it started after i ok'ed a software update (minor, not distro upgrade).
The gnome shell terminates, i get back to the login. It mainly seems to happen when i open a webbrowser, but also other situations, eg. opening an unconfigured thunderbird.

A few times, i also got different error windows within gnome "system error detected" or similar:
[update]
I did a separate Question on the different error-messages:
'System Program Problem Detected' vs "Sorry, Ubuntu * has experienced an internal error"
[/update]

At first, i tried different things like apt-get update/upgrade, where i got some Hash Sum mismatch errors . Lots of experimenting with clear and –fix-missing got me around this, but the crashing persisted. So after a snapshot in virtualbox, i did the upgrade to 20 04, hoping that would fix the unknown problem along the way.
But no, it did not.
I found some tips recommending to look at the output of journalctl -e and other logfiles. But there's way too much stuff, and i don't know what to look into and what to look over.
in /var/log/boot.log i see some fails,

Failed to start Snap Daemon. [repeatedly]
Failed to start Docker Application Container Engine. [repeatedly]
Failed to start Wait until snapd is fully seeded.
Failed to start containerd container runtime.
Failed to start GRUB failed boot detection.


i see some logs in /var/crash:

_usr_bin_gnome-shell.1000.crash
_usr_bin_gnome-software.1000.crash
_usr_lib_gdm3_gdm-session-worker.0.crash
_usr_lib_policykit-1_polkitd.0.crash


How could i get closer to finding the problem's source?

Wayland and Switcheroo, not that i know of. It is a default 1804 install.

A propos Switcheroo, i am on a Dell Precision with Quadro M2000M. Switchable Graphics is "off" in the bios, i tried "on", same effect.

~$dpkg -l *irtualbox* Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Architecture Description +++-========================-============-============-================================= un virtualbox-guest-dkms <none> <none> (no description available) un virtualbox-guest-modules <none> <none> (no description available) ~$ ls -al ~/.local/share/gnome-shell/extensions
ls: cannot access '/home/toro/.local/share/gnome-shell/extensions': No such file or directory

~$ls -al /usr/share/gnome-shell/extensions total 20 drwxr-xr-x 5 root root 4096 Okt 7 17:52 . drwxr-xr-x 7 root root 4096 Okt 7 17:56 .. drwxr-xr-x 2 root root 4096 Okt 7 17:52 desktop-icons@csoriano drwxr-xr-x 3 root root 4096 Okt 7 17:45 ubuntu-appindicators@ubuntu.com drwxr-xr-x 3 root root 4096 Okt 7 17:45 ubuntu-dock@ubuntu.com  Virtualbox runs on latest win10x64. I tried different graphics Settings with and without 3d accel., Made no difference. #### Best Answer • I've also been getting these gnome-shell crashes on my Jetson Nano 4.9.140-tegra aarch64 kernel running Ubuntu 18.04.5 LTS since doing some minor updates last week. My /var/log/apport.log showed: ERROR: apport (pid 22141) Tue Oct 27 08:41:37 2020: executable: /usr/lib/tracker/tracker-extract (command line "/usr/li$

which, I believe means the /usr/lib/tracker/tracker-extract executable file is corrupt. So I simply deleted it with:

sudo rm -rf /usr/lib/tracker/tracker-extract

and cleared /var/crash so I could monitor new crash reports. I have now rebooted several times without incident.

I also got:

ERROR: apport (pid 7017) Mon Oct 26 00:14:28 2020: executable: /usr/lib/gdm3/gdm-session-worker (command line "gdm-sess\$

ERROR: apport (pid 7017) Mon Oct 26 00:14:28 2020: is_closing_session(): no DBUS_SESSION_BUS_ADDRESS in environment

but I think this may be due to the corrupt tracker-extract executable, as it has not recurred after removing the corrupt executable. Hope this helps.