Baa's questions

I'm trying to change my MTU size on my ethernet interface.

I'm just using Ubuntu 22 Desktop, i've set my MTU value to 10000 through the Gnome network settings:

I've then restarted NetworkManager sudo restart NetworkManager.

My MTU does not seem to change when I check with ifconfig:

ifconfig | grep mtu
enp39s0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST>  mtu 1500

This is my whole NetworkManager profile from /etc/NetworkManager/system-connections/Wired connection 1.nmconnection:

[connection]
id=Wired connection 1
uuid=02d40a9e-d675-390b-a1d1-f28ff3b23880
type=ethernet
autoconnect-priority=-999
interface-name=enp39s0
metered=2
timestamp=1697903662

[ethernet]
mtu=10000

[ipv4]
address1=192.168.178.2/24,192.168.178.1
method=manual

[ipv6]
addr-gen-mode=stable-privacy
method=auto

[proxy]

I have not manually modified this file, only used the GUI.

The NetPlan configuration is unchanged from default:

# Let NetworkManager manage all devices on this system
network:
  version: 2
  renderer: NetworkManager

nmcli appears to be set correctly nmcli connection show 'Wired connection 1' | grep mt:
802-3-ethernet.mtu: 10000

I'm stumped, does the interface inside ifconfig not represent what NetworkManger changes? Has it actually been changed? I can't tell.

The output of ip -d link list dev enp39s0 is:

2: enp39s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc fq_codel state UP mode DEFAULT group default qlen 1000
    link/ether <MAC was here> brd ff:ff:ff:ff:ff:ff promiscuity 0 minmtu 68 maxmtu 9194 addrgenmode none numtxqueues 1 numrxqueues 1 gso_max_size 64000 gso_max_segs 64 parentbus pci parentdev 0000:27:00.0

I am using Ubuntu 22.04 with Wayland for a kiosk system and need a way to hide the mouse cursor.

Most answers such as this one rely on x applications that won't work in Wayland so looking for a new solution.

I am trying to use Ubuntu Server 22.04 on a Raspberry Pi 4. I have installed the packages ubuntu-desktop-minimal and rebooted but I get no login screen on the Pi only a blinking dash.

I have also tried the ubuntu-desktop-raspi and ubuntu-desktop packages to no avail.

I have also tried editing /etc/gdm3/custom.conf and uncommenting WaylandEnable=false to try without Wayland but the result was the same.

During boot the screen appears to work ok I get the boot logs appearing on my monitor etc.

GDM seems to be running but showing this in the log:

Jun 20 16:58:18 SYKIOSKPI gdm-launch-environment][1232]: pam_unix(gdm-launch-environment:session): session closed for user gdm
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1232]: pam_unix(gdm-launch-environment:session): session opened for user gdm(uid=116) by (uid=0)
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: Child process -1227 was already dead.
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: Child process -1227 was already dead.
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1221]: GLib-GObject: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1221]: pam_unix(gdm-launch-environment:session): session closed for user gdm
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1221]: pam_unix(gdm-launch-environment:session): session opened for user gdm(uid=116) by (uid=0)
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: Child process -1217 was already dead.
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: Child process -1217 was already dead.
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1211]: GLib-GObject: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1211]: pam_unix(gdm-launch-environment:session): session closed for user gdm
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1211]: pam_unix(gdm-launch-environment:session): session opened for user gdm(uid=116) by (uid=0)
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: Child process -1207 was already dead.
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: Child process -1207 was already dead.
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1200]: GLib-GObject: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1200]: pam_unix(gdm-launch-environment:session): session closed for user gdm
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1200]: pam_unix(gdm-launch-environment:session): session opened for user gdm(uid=116) by (uid=0)
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: Child process -1187 was already dead.
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: Child process -1187 was already dead.
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1177]: GLib-GObject: g_object_unref: assertion 'G_IS_OBJECT (object)' failed
Jun 20 16:58:17 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:17 SYKIOSKPI gdm-launch-environment][1177]: pam_unix(gdm-launch-environment:session): session closed for user gdm
Jun 20 16:58:16 SYKIOSKPI gdm-launch-environment][1177]: pam_unix(gdm-launch-environment:session): session opened for user gdm(uid=116) by (uid=0)
Jun 20 16:58:16 SYKIOSKPI gdm3[1086]: Gdm: Child process -1165 was already dead.
Jun 20 16:58:16 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:58:16 SYKIOSKPI gdm3[1086]: Gdm: Child process -1165 was already dead.
Jun 20 16:58:16 SYKIOSKPI gdm3[1086]: Gdm: GdmDisplay: Session never registered, failing
Jun 20 16:57:43 SYKIOSKPI gdm-launch-environment][1149]: pam_unix(gdm-launch-environment:session): session opened for user gdm(uid=116) by (uid=0)
Jun 20 16:57:33 SYKIOSKPI systemd[1]: Started GNOME Display Manager.
Jun 20 16:57:33 SYKIOSKPI systemd[1]: Starting GNOME Display Manager...

I've enabled debug in GDM and ran it again, log can be found here: https://pastebin.com/ze8PWHEd

This is the GDM X server log: https://pastebin.com/c4uTZRVn

Unsure what to try next

I am setting up a kiosk using Ubuntu server 22.04 that only runs a Web Browser. Do I need to install the full desktop environment to achieve this or is there a way I can run only FireFox?

Previously I would consider running a minimal x desktop but I'd like to stick with Wayland if possible and it might have a better solution.

Today I upgrade to Ubuntu 22.04 from 20.04 and the nightlight / bluelight filter isn't working anymore.

It shows as turned on in in Settings menu but isn't changing anything.

How do I diagnose and/or fix this?

In order to run windowed programs at the maximum possible size I can set their resolution to the resolution of my monitor, but then there are several pixels off-screen below the window because the window is positioned below the Gnome Top Bar.

If I knew the size of the top-bar I could account for that, is there a way to find out what size it is exactly?

I am creating a custom Ubuntu ISO that once installed runs a kiosk program.

My issue is that the Kiosk program launches and can be seen while Ubuntu is still installing.

My idea is to edit the systemd file and add a requires= category and specify a process that runs during normal system operation but not during installation. I'd like to know a process that does that, or another method of preventing a systemd process from launching during installation.

I am trying to use sftp to pull a file from a remote server.

Both client and server-side users are created with adduser --system and their shell is /usr/sbin/nologin. The users are called legit-backup.

Public-key authorisation has been configured for the client user to have SSH access to the server as a user of the same name. When I try to pull down the file /home/legit-backup/test a file using the command sudo -u legit-backup scp legit-backup@<remote-server>:~/test, I receive the error protocol error: mtime.sec not present, no files copy down.

If I change the remote user's shell to /bin/bash then sftp works as normal.

I wan to use /usr/sbin/nologin for security reasons, the user should not be able to have SSH access other than sftp, is it possible?

I find that some applications want to check /proc/cpuinfo but don't have access

This is on my server running Ubuntu 20.04.2 LTS, the permissions are:

-rw-r----- 1 root root 0 May  2 14:35 /proc/cpuinfo

My desktop is also running Ubuntu 20.04.2 LTS but the permissions are different and less restrictive:

-r--r--r-- 1 root root 0 May  2 15:37 /proc/cpuinfo

Which one is correct? Are they restrictive on my server for a reason? Can I update my server's permissions to be the same as my desktop or is that dangerous?

When I open an application it uses my default PulseAudio output device.

I would like to force a specific application to always use a different device, is this possible?

I need to troubleshoot my installation failure. From the installer I can access the terminal using ALT + F2 but I still need user credentials.

Is there a default root login I can use during the installation? I'm installing a custom ISO based on Ubuntu 19.10

So far I've tried:

• Username: root
• Password: root

• Username: ubuntu
• Password: ubuntu

• Username: root
• Password: ubuntu

• Username: root
• Password:

• Username: ubuntu
• Password:

I've been trying to automate my installation of 19.04 using pre-seeding files. I'm booting directly from installation media copied to a USB stick.

So far, nothing I've tried has worked. Subiquity loads as normal and presents the user interface to manually install.

This is my grub.cfg

if loadfont /boot/grub/font.pf2 ; then
    set gfxmode=auto
    insmod efi_gop
    insmod efi_uga
    insmod gfxterm
    terminal_output gfxterm
fi

set menu_color_normal=white/black
set menu_color_highlight=black/light-gray

set timeout=1
menuentry "Install Ubuntu Server" {
    set gfxpayload=keep
    linux   /casper/vmlinuz  file=/cdrom/preseed/magicmirror.seed boot=casper quiet splash ---
    initrd  /casper/initrd
}

My pre-seeding file is from here: https://github.com/core-process/linux-unattended-installation/blob/master/ubuntu/18.04/custom/preseed.cfg

I'm not expecting it to work unchanged, but I was expecting it to error or give some indication that the pre-seeding file had been loaded.

I've also tried loading a Kickstarter but I got the same result.

Am I loading the pre-seeding file wrong, or has automated installation changed in 19.04?

I have a device with an AMD64 CPU but a UEFI bootloader that only supports i386.

I have made a custom Ubuntu 19.04 ISO installer using Cubic and have flashed it to a USB using usb-creator-gtk (Startup Disk Creator).

This creates two partitions on the USB:

The first partition formatted as ISO9660 and holds the ISO contents, the second is a FAT32 partition that contains only the .EFI boot files.

The second partition is what the tablet will boot from. Its contents come from an efi.img file stored inside /boot/grub on the ISO. This originally contained only AMD64 EFI files.:

I have created my own replacement img.efi file and input a bootia32.efi file using these commands:

dd if=/dev/zero of=efi.img bs=1M count=5
mkfs.fat efi.img
sudo mount -o loop,rw efi.img /media/efi
sudo cp -r <files> /media/efi

This successfully makes a bootable USB, however it doesn't load the installer Grub, it only loads a Grub command line.

I've used this bootia32.efi file to successfully load grub before, if I instead manually format the USB as FAT32, copy over the ISO files and put the custom EFI file inside of /EFI/BOOT then the device will boot into Grub as I would expect.

But I'd like to make an ISO that can be flashed as normal and boot fine.

My question is, what is the point of creating a separate partition to hold the boot EFI files as usb-creator-gtk does? How do I make that partition load the installer's Grub config instead of just the Grub command line?

Thank you

I noticed yesterday that the nightlight in Ubuntu has stopped working, it's turned on in the settings.

I've also checked dconf-editor, it is turned on in there as well.

I'm running Ubuntu 18.04 with proprietary Nvidia drivers, they're running the latest update available through the repository 410.

Any advice is appreciated

I am running Ubuntu 18.04

Sometimes, I'll play a media file and it would have been encoded badly and there will be a very high-pitched whine in the background.

Is it possible to block sound from being played above a certain frequency?

I have run the following script to set permissions into /etc/nginx

#!/usr/bin/env bash

sudo chown -R root:root /etc/nginx
sudo chmod -R 0750 /etc/nginx
sudo setfacl -Rbk -m g:hugo:rwx /etc/nginx
sudo setfacl -R --mask -m g:www-data:rx /etc/nginx

However, when I check the permissions afterwards there is a discrepancy in the results for the 'group' of ls -al and getfacl

$ ls -al /etc/nginx
total 24
drwxrwx---+   5 root root 4096 Mar 18 17:07 .

$ getfacl /etc/nginx
getfacl: Removing leading '/' from absolute path names
# file: etc/nginx
# owner: root
# group: root
user::rwx
group::r-x
group:www-data:r-x
group:hugo:rwx
mask::rwx
other::---

Why?

I am currently running Server with no gui, i'd like to use the most lightweight gui possible since this installation will only be used to control one application.

So far i've tried

sudo apt-get install xorg openbox obconf

but no gui launches at startup

If I run exec openbox-session it will reset back to the login screen, I think it might print an error for half a second but it's too fast for me to see.

I am trying to install Cockpit http://cockpit-project.org on my Ubuntu server 16.04

Unfortunately, I installed it a long time ago, and now that i've come back to it it won't launch and I didn't know why or where to start. So I tried to remove it and re-install to start from scratch...

So I did sudo apt purge --auto-remove cockpit

It processed it for a few seconds but didn't delete any of the directories, when I reinstalled it didn't overwrite any of them either :(

So I tried again, but this time deleted /etc/cockpit myself afterwards, but when I reinstall it doesn't re-create the directory either D:

What should I do next?...

I have a single extra HardDrive encrypted with VeraCrypt in Ubuntu Gnome 16.04.

I'd like to use it to store my Documents, Photos etc, but I can't easily redirect the home links if the drive is not mounted at startup.

The command to mount it normally would be:

veracrypt --mount /dev/sda1

Typically this brings up a GUI but I think if without one it would let me input the password in the terminal.

Is there anyway I can do this during boot? I've so far attempting putting the line in /etc/rc.local as another website suggested but it did not work :(

If it's relevant, i'm currently booting without the splash screen due to another issue I had with inputting the password to unlock /

Thanks.

I am using a Huawei E3531 with a new SIM card and empty Micro SD. I have also attempted a Nokia Symbian Phone, and some generic Qualcom device.

After some forum digging I managed to get my Huawei to connect me to the internet fine, however what I actually wanted to use it for was receiving SMS.

I am attempting to use ModemManager and ModemManager Gui to do this.

Only once did ModemManager Gui display my Huawei which was after running

modeprobe option

It only showed it for a few minutes and shortly after disappeared again, the command no longer produces the same result.

The modem only started connecting to the internet after doing:

sudo nano /etc/udev/rules.d/99-axe027.rules

And inputting:

# /etc/udev/rules.d/99-axe027.rules
# contains axe027 udev rule to patch default
# FTDI product id to AXE027 product id (0xbd90)
SYSFS{idProduct}=="12d1",
SYSFS{idVendor}=="1f01",
RUN+="/sbin/modprobe -q ftdi_sio product=0x12d1 vendor=0x1f01"

Which was generously provided by this forum post.

usb-devices result for the correct device produces:

T:  Bus=01 Lev=01 Prnt=01 Port=07 Cnt=06 Dev#= 14 Spd=480 MxCh= 0
D:  Ver= 2.00 Cls=02(commc) Sub=00 Prot=00 MxPS=64 #Cfgs=  1
P:  Vendor=12d1 ProdID=14dc Rev=01.02
S:  Manufacturer=HUAWEI
S:  Product=HUAWEI Mobile
C:  #Ifs= 3 Cfg#= 1 Atr=80 MxPwr=500mA
I:  If#= 0 Alt= 0 #EPs= 1 Cls=02(commc) Sub=06 Prot=00 Driver=cdc_ether
I:  If#= 1 Alt= 0 #EPs= 2 Cls=0a(data ) Sub=06 Prot=00 Driver=cdc_ether
I:  If#= 2 Alt= 0 #EPs= 2 Cls=08(stor.) Sub=06 Prot=50 Driver=usb-storage

Now the important part: the result of sudo systemctl status ModemManager

● ModemManager.service - Modem Manager
   Loaded: loaded (/lib/systemd/system/ModemManager.service; disabled; vendor preset: enabled)
   Active: active (running) since Wed 2016-09-14 19:16:08 BST; 40min ago
 Main PID: 9697 (ModemManager)
   CGroup: /system.slice/ModemManager.service
           └─9697 /usr/sbin/ModemManager

Sep 14 19:16:08 Hugo-Gnome systemd[1]: Starting Modem Manager...
Sep 14 19:16:08 Hugo-Gnome ModemManager[9697]: <info>  ModemManager (version 1.4.12) starting in system bus...
Sep 14 19:16:08 Hugo-Gnome systemd[1]: Started Modem Manager.
Sep 14 19:16:10 Hugo-Gnome ModemManager[9697]: <info>  Couldn't find support for device at '/sys/devices/pci0000:00/0000:00:14.0/usb1/1-8': not supported by any plugin
Sep 14 19:16:10 Hugo-Gnome ModemManager[9697]: <info>  Couldn't find support for device at '/sys/devices/pci0000:00/0000:00:1d.2/0000:03:00.0': not supported by any plugin

I've been looking for a solution for a couple days now and no luck :(

Any advice is greatly appreciated!

I may attempt to draw an image based on the username of the most helpful answer (depending on whether or not my graphics tablet works in Ubuntu...)