Recently Ubuntu moved LXC into snaps which raises a concern with snapd updates. Those updates can not be configured to be manual, they run on schedule and can't be turned off. As I am thinking to have a NAS and a VPN servers running in LXC containers but I am concerned whether snapd updates will be shutting down or restarting those containers and therefore causing potential data loss with NAS or security issues with VPN.
LXC/LXD used to be implemented as native packages until 18.04. Since 18.04 LXC containers are run as snaps. I wonder if this imposes a runtime overhead. This would negate the idea of having light-weight containers. So my predicament is whether it is worth performance wise to run sandboxed environments as LXCs vs having a virtualized environment.
I am cleaning up my fresh Ubuntu 20.04 install and I can't seem to remove core18 snap.
$ snap list
Name Version Rev Tracking Publisher Notes
core18 20200427 1754 latest/stable canonical✓ base
lxd 4.1 15359 latest/stable/… canonical✓ -
snapd 2.45 7777 latest/stable canonical✓ snapd
$ snap remove core18
error: cannot remove "core18": snap "core18" is not removable: snap is being used by snap lxd.
What IS core18 and why do I need it so much that it won't let me remove it? Most online references I found say it is for IoT or embedded devices. Since my workstation is such a device I don't see why I need it. I am planning to use lxc containers but why do I need core18 for that?
I first freshly installed Ubuntu 20.04 server and then xubuntu-desktop on top of it. I immediately noticed that many applications were missing main menus. The examples I remember were got-cola and libre office from the main repository. Also Microsoft Visual Studio Code (from Microsoft repo) didn't have it. Thunar at some point didn't have it but after me tinkering around got them back. There were a few other apps without menus but I don't remember what they were.
I already know the answer but I am posting it as a question if someone else is experiencing the same issues. I am giving my solution below and hoping it may help others.
I am setting up a "special" environment for user john on my workstation running XFCE desktop. When john signs I want to tweak system configuration which requires root access. I am looking for a way to run a script as root upon user signing into XFCE which would check user name and make tweaks as necessary.
My research led me to the idea of putting my script in /etc/lightdm/lightdm.conf.d/ and use session-setup-script. But am not sure if it is the right place. I need an advice from a guru.
I just got myself a beautiful 27" WQHD display. It is connected to HDMI (no VideoPort) and works great showing 2560x1440 @ 60 Hz.
There is a problem however. When it goes to sleep/I turn the monitor off and then I wake it up/turn it on it doesn't come back. It stays blank eventually displaying "no signal".
The weird thing is when I switch to a different TTY, e.g. Ctrl+Alt+F2 it wakes up, but then going back to Ctrl+Alt+F7 immediately puts it back to sleep and shows "no signal" message. Currently I have to run service lightdm restart in a different TTY in order to wake the monitor up, which is better than reboot but far from ideal. The fact that it can be woken up by switching to a different TTY or restarting X tells me that it is a software related problem.
I am looking for any reasonable solution e.g.
- configuration tweak which will force it wake up on keypress
- a command that I could give a hot key combination which will wake up the monitor
- a driver install/update
- anything else that works
As I am running out of ideas I would appreciate any advice, thoughts, guesses. Thanxalot!
P.S. I run xubuntu 16.04 and use Intel® HD Graphics 4600