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28
votes
8
answers
40878
views
Terminal - copy from CLI without using mouse
While firing commands in CLI, **I want to copy the command I just fired** or anything I wrote in terminal and **paste it somewhere else** without using mouse. Like in following picture, I want to copy the update command (completely or partially) without using mouse and paste it somewhere. 
prayagupadhyay
(5047 rep)
Sep 22, 2013, 07:41 AM
• Last activity: Aug 12, 2025, 02:47 AM
0
votes
1
answers
40
views
How do I recieve MMS messages in Spacebar with AT&T/ATT?
I have KDE's [Spacebar][1] installed on my Librem 5 but cannot figure out how to access/receive MMS messages. (edited image example) [![Screenshot of Spacebar with MMS Message][2]][2] I added my MMS settings but still get the message above: [![enter image description here][3]][3] Have any of you bee...
I have KDE's Spacebar installed on my Librem 5 but cannot figure out how to access/receive MMS messages.
(edited image example)
I added my MMS settings but still get the message above:
Have any of you been able to receive MMS messages? I am attempting to receive cat photos.
The screenshot was taken on Mobian.
**Edit**: I am using AT&T (sometimes refered to as ATT) but would prefer a carrier-independent solution so that other may recieve help here as well


newunix
(189 rep)
Aug 11, 2025, 04:58 AM
• Last activity: Aug 12, 2025, 02:21 AM
4
votes
2
answers
3236
views
os-prober giving wrong UUID for Arch Linux
Up until yesterday, everything was working find and os-prober was successfully generating menu entries for the Arch Linux install. However today when I tried to boot into Arch, I got an error that the root file system could not be found at the UUID it was trying to use. After some tinkering I was ab...
Up until yesterday, everything was working find and os-prober was successfully generating menu entries for the Arch Linux install. However today when I tried to boot into Arch, I got an error that the root file system could not be found at the UUID it was trying to use. After some tinkering I was able to get Arch to boot by manually changing the root to the actual partition "/dev/sda7" as opposed to using UUID.
I was wondering what might cause os-prober to be generating this invalid configuration just for the Arch Linux install. It does fine still for the openSUSE and Windows 7 installs. One other thing to note is that it has added "rw quiet" to the end of the boot line for Arch Linux. That is not something it previously did, and I am wondering if whatever changed that has to do with why the UUID is incorrect.
Below I will post the menu entry for Arch Linux. As you can see os-prober has the --set-root= 'some UUID' part with the correct UUID, but later on when booting linux it has -root=UUID='some other incorrect UUID'.
Just to clarify, I have Ubuntu, Arch Linux, openSUSE, and Windows 7 on this machine, but I am using Ubuntu as the main OS and allowing it to manage GRUB and its configurations. All of the operating systems are at their most up-to-date versions.
menuentry 'Arch (on /dev/sda7)' --class gnu-linux --class gnu --class os $menuentry_id_option 'osprober-gnulinux-simple-b9522736-878c-49e3-b30d-ad65589aa1d9' {
insmod part_msdos
insmod ext2
set root='hd0,msdos7'
if [ x$feature_platform_search_hint = xy ]; then
search --no-floppy --fs-uuid --set=root --hint-bios=hd0,msdos7 --hint-efi=hd0,msdos7 --hint-baremetal=ahci0,msdos7 b9522736-878c-49e3-b30d-ad65589aa1d9
else
search --no-floppy --fs-uuid --set=root b9522736-878c-49e3-b30d-ad65589aa1d9
fi
linux /boot/vmlinuz-linux root=UUID=ad4103fa-d940-47ca-8506-301d8071d467 rw quiet
initrd /boot/initramfs-linux.img
}
As you can see the first two UUIDs are different from the last one. The first two are correct and the last one is wrong. If I replace the last UUID with '/dev/sda7', Then it boots without problem. I have manually edited the grub.cfg to do this, but I would like os-prober to get back to working automatically. Thanks.
user256518
May 10, 2014, 03:42 PM
• Last activity: Aug 12, 2025, 02:07 AM
2
votes
1
answers
3142
views
Where are kernel and initramfs files for systemd-boot?
I'm trying to do a fresh install and use `systemd-boot` as the bootloader for my ESP, but in the [install instructions](https://wiki.archlinux.org/index.php/systemd-boot#EFI_boot) on step 4 it says: > Copy your kernel and initramfs onto that ESP. But where are `vmlinuz-linux` and `initramfs-linux.im...
I'm trying to do a fresh install and use
systemd-boot
as the bootloader for my ESP, but in the [install instructions](https://wiki.archlinux.org/index.php/systemd-boot#EFI_boot) on step 4 it says:
> Copy your kernel and initramfs onto that ESP.
But where are vmlinuz-linux
and initramfs-linux.img
located? I can't find them for the life of me. Do I need to install bootctl
before those files are available? Nothing exists in /boot
in either my Arch Linux install disk or the partitions that I'm working with
starscream_disco_party
(165 rep)
Aug 4, 2016, 05:35 PM
• Last activity: Aug 12, 2025, 02:01 AM
5
votes
1
answers
6268
views
Two *different* mount points having the *same* absolute path (bind-mount problem)
Scenario -------- - a NFS share is mounted on `/mnt/temp/dir` (and other shares are mounted in subdirectories), - I `umount` everything there but supposedly, it doesn't work well (maybe I start with `umount /mnt/temp/dir` instead of umounting "nested" shares like `/mnt/temp/dir/subdir*` first), - I...
Scenario
--------
- a NFS share is mounted on
/mnt/temp/dir
(and other shares are mounted in subdirectories),
- I umount
everything there but supposedly, it doesn't work well (maybe I start with umount /mnt/temp/dir
instead of umounting "nested" shares like /mnt/temp/dir/subdir*
first),
- I do mount -o bind /data/temp /mnt/temp
,
- I do mount /mnt/temp/dir
,
- I do mount /mnt/temp/dir/subdir1
... and it works well.
Note: /mnt/temp
is initially hosted on the root (/
) filesystem /dev/sda6
, and /data
is another filesystem from /dev/sda8
.
Problem
-------
I cannot delete the /mnt/temp/dir
directory on the root filesystem:
# mount -o bind / /test/root
# rmdir /test/root/mnt/temp/dir
rmdir: failed to remove `dir': Device or resource busy
Some explanation
-----------------
/mnt/temp/dir
is mounted ***twice***, probably once on the root fs, and once on the /data
fs.
Here is cat /proc/mounts
:
nfsserver:/some/share/ /mnt/temp/dir nfs rw,relatime(...) 0 0
nfsserver:/some/share/ /mnt/temp/dir nfs rw,relatime,(...) 0 0
More interesting, here is cat /proc/1/mountinfo
:
29 20 0:18 / /mnt/temp/dir rw,relatime - nfs nfsserver:/some/share/ rw,(...)
33 31 0:18 / /mnt/temp/dir rw,relatime - nfs nfsserver:/some/share/ rw,(...)
See, the two numbers at the beginning are *different*.
Kernel doc says for these two fields:
(1) mount ID: unique identifier of the mount (may be reused after umount)
(2) parent ID: ID of parent (or of self for the top of the mount tree)
They also have different parents 20 and 31 (root fs and /data
fs), see:
20 1 8:6 / / rw,relatime - ext4 /dev/sda6 rw,(...)
31 20 8:8 /temp /mnt/temp rw,relatime - ext4 /dev/sda8 rw,(...)
If I try to umount /mnt/temp/dir
, I get 2 error messages:
umount.nfs: /mnt/temp/dir: device is busy
umount.nfs: /mnt/temp/dir: device is busy
Question
========
**How can I umount
the "bad" one (mount ID 29)?**
Even the umount(2)
system call takes a path for argument, and not a "mount ID".
Totor
(21040 rep)
Feb 27, 2015, 06:24 PM
• Last activity: Aug 12, 2025, 01:06 AM
0
votes
1
answers
57
views
Debian Trixie: problems with Lxc unprivileged Containers
On Debian 12 bullseye all works fine. This is the situation on Debian Trixie (released stable some days ago) lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3227 to "net" of 3 lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed...
On Debian 12 bullseye all works fine.
This is the situation on Debian Trixie (released stable some days ago)
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3227 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3312 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3312 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3312 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3382 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3382 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3382 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3436 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3436 to "net" of 3
lxc-ls: ../src/lxc/utils.c: switch_to_ns: 900 Operation not permitted - Failed to set process 3436 to "net" of 3
NAME STATE AUTOSTART GROUPS IPV4 IPV6 UNPRIVILEGED
cacti1 RUNNING 0 - - - true
certauth1 RUNNING 0 - - - true
dns1 RUNNING 0 - - - true
Seems working, but..
lxc-attach dns1
lxc-attach: dns1: ../src/lxc/cgroups/cgfsng.c: enter_scope: 1335 Failed opening dbus connection
lxc-attach: dns1: ../src/lxc/cgroups/cgfsng.c: cgroup_attach_move_into_leaf: 2859 Failed entering scope 'lxc-dns1-0.scope'
lxc-attach: dns1: ../src/lxc/cgroups/cgfsng.c: cgroup_attach_move_into_leaf: 2897 Permission denied - Failed to move process into target cgroup via fd 7 and 8
lxc-attach: dns1: ../src/lxc/conf.c: userns_exec_minimal: 4685 Permission denied - Running parent function failed
lxcunpriv@nas:~$ lxc-attach: dns1: ../src/lxc/attach.c: do_attach: 1238 No data available - Failed to receive lsm label fd
lxc-attach: dns1: ../src/lxc/attach.c: do_attach: 1376 Failed to attach to container
The containers are unprivileged
I have tried with
systemd.unified_cgroup_hierarchy=false
and not but same result.
After some seconds all containers fails
NAME STATE AUTOSTART GROUPS IPV4 IPV6 UNPRIVILEGED
cacti1 STOPPED 0 - - - true
certauth1 STOPPED 0 - - - true
dns1 STOPPED 0 - - - true
Trying with debug
lxc-start -n dns1 -F -l DEBUG -o /tmp/lxc-nomecontainer.log
lxc-start: dns1: ../src/lxc/cgroups/cgfsng.c: unpriv_systemd_create_scope: 1526 Failed opening dbus connection
Failed to mount cgroup at /sys/fs/cgroup/systemd: Operation not permitted
[!!!!!!] Failed to mount API filesystems.
Exiting PID 1...
lxc-checkconfig report all fine
lxc-checkconfig
LXC version 6.0.4
Kernel configuration not found at /proc/config.gz; searching...
Kernel configuration found at /boot/config-6.12.38+deb13-amd64
--- Namespaces ---
Namespaces: enabled
Utsname namespace: enabled
Ipc namespace: enabled
Pid namespace: enabled
User namespace: enabled
Network namespace: enabled
Namespace limits:
cgroup: 127838
ipc: 127838
mnt: 127838
net: 127838
pid: 127838
time: 127838
user: 127838
uts: 127838
--- Control groups ---
Cgroups: enabled
Cgroup namespace: enabled
Cgroup v1 mount points:
Cgroup v2 mount points:
- /sys/fs/cgroup
Cgroup device: enabled
Cgroup sched: enabled
Cgroup cpu account: enabled
Cgroup memory controller: enabled
Cgroup cpuset: enabled
--- Misc ---
Veth pair device: enabled, loaded
Macvlan: enabled, not loaded
Vlan: enabled, loaded
Bridges: enabled, loaded
Advanced netfilter: enabled, loaded
CONFIG_IP_NF_TARGET_MASQUERADE: enabled, not loaded
CONFIG_IP6_NF_TARGET_MASQUERADE: enabled, not loaded
CONFIG_NETFILTER_XT_TARGET_CHECKSUM: enabled, not loaded
CONFIG_NETFILTER_XT_MATCH_COMMENT: enabled, not loaded
FUSE (for use with lxcfs): enabled, not loaded
--- Checkpoint/Restore ---
checkpoint restore: enabled
CONFIG_FHANDLE: enabled
CONFIG_EVENTFD: enabled
CONFIG_EPOLL: enabled
CONFIG_UNIX_DIAG: enabled
CONFIG_INET_DIAG: enabled
CONFIG_PACKET_DIAG: enabled
CONFIG_NETLINK_DIAG: enabled
File capabilities: enabled
Note: Before booting a new kernel, you can check its configuration with:
CONFIG=/path/to/config /usr/bin/lxc-checkconfig
Any idea?
EDIT1: This script which fix something on some lxc versions fail completely
#!/bin/bash
# this is for the password in cache
printf '\n\033[42mCreating cgroup hierarchy\033[m\n\n' &&
for d in /sys/fs/cgroup/*; do
f=$(basename $d)
echo "looking at $f"
if [ "$f" = "cpuset" ]; then
echo 1 | sudo tee -a $d/cgroup.clone_children;
elif [ "$f" = "memory" ]; then
echo 1 | sudo tee -a $d/memory.use_hierarchy;
fi
sudo mkdir -p $d/$USER
sudo chown -R $USER $d/$USER
# add current process to cgroup
#echo $PPID > $d/$USER/tasks
done
mkdir: cannot create directory ‘/sys/fs/cgroup/cgroup.controllers’: not a directory
chown: impossible to access on '/sys/fs/cgroup/cgroup.controllers/lxcunpriv': not a directory
elbarna
(13738 rep)
Aug 10, 2025, 02:06 AM
• Last activity: Aug 12, 2025, 12:23 AM
9
votes
3
answers
6892
views
Is there a way to empty the trash/wastebasket from the command line?
This would be great especially considering the latest version of Ubuntu is very slow when displaying directories on my PC...
This would be great especially considering the latest version of Ubuntu is very slow when displaying directories on my PC...
ixtmixilix
(13530 rep)
Oct 10, 2010, 10:22 PM
• Last activity: Aug 12, 2025, 12:22 AM
0
votes
1
answers
3856
views
How to disable ModemManager in linux mint?
When I setting up qmk_firmware, it throws ``` ⚠ Detected ModemManager. Please disable it if you are using a Pro-Micro. Ψ Problems detected, please fix these problems before proceeding. ``` I've tried both `systemctl disable ModemManager.service` and `sudo mv /usr/share/dbus-1/system-services/org.fre...
When I setting up qmk_firmware, it throws
⚠ Detected ModemManager. Please disable it if you are using a Pro-Micro.
Ψ Problems detected, please fix these problems before proceeding.
I've tried both systemctl disable ModemManager.service
and sudo mv /usr/share/dbus-1/system-services/org.freedesktop.ModemManager1.service /usr/share/dbus-1/system-services/org.freedesktop.ModemManager1.service.disabled
, but neither works. Also tried to logout and in.
Didn't see any logs from this though.
$ systemctl list-dependencies multi-user.target | grep Modem
Mengo
(103 rep)
Sep 13, 2020, 11:30 PM
• Last activity: Aug 12, 2025, 12:00 AM
80
votes
4
answers
12779
views
I accidentally typed my password into the login field, is it still secure?
I was looking down at my keyboard and typed my password in because I thought I had already typed my login name. I pressed Enter , then when it asked for the password I pressed Ctrl + c . Should I take some precautionary measure to make sure the password isn't stored in plain text somewhere or should...
I was looking down at my keyboard and typed my password in because I thought I had already typed my login name. I pressed Enter, then when it asked for the password I pressed Ctrl+c.
Should I take some precautionary measure to make sure the password isn't stored in plain text somewhere or should I change the password?
Also this was on a tty on ubuntu server 16.04 LTS.
hermancain
(1309 rep)
Apr 24, 2016, 09:38 PM
• Last activity: Aug 11, 2025, 11:37 PM
3
votes
1
answers
2064
views
Value of /proc/sys/kernel/hostname
I've set computer hostname in `/etc/hostname` a while ago (also there are record in `/etc/hosts`). Everything worked fine, but recently I've noticed that value of `hostname` (and `/proc/sys/kernel/hostname`) changed (to hostname of neighbour computer), although I haven't touched anything related. Va...
I've set computer hostname in
/etc/hostname
a while ago (also there are record in /etc/hosts
). Everything worked fine, but recently I've noticed that value of hostname
(and /proc/sys/kernel/hostname
) changed (to hostname of neighbour computer), although I haven't touched anything related. Value of /etc/hostname
remains correct. Which mechanism may cause such change?
There are similar problem description , but it doesn't contains any solution.
valodzka
(405 rep)
Nov 22, 2013, 01:33 PM
• Last activity: Aug 11, 2025, 11:03 PM
3
votes
1
answers
2499
views
Debian apt issue (not found and deb12u1)
I wanted to install texmaker the other day but I ran into an issue : it downloaded 500mb but it told me it could not find a few dependencies, for instance `Err : 4 http://deb.debian.org/debian/pool/main/t/texlive-bin/texlive-binaries_2022.20220321.62855-5.1_amd64.deb 404 Not Found [IP : .... 80]` I...
I wanted to install texmaker the other day but I ran into an issue : it downloaded 500mb but it told me it could not find a few dependencies, for instance
Err : 4 http://deb.debian.org/debian/pool/main/t/texlive-bin/texlive-binaries_2022.20220321.62855-5.1_amd64.deb 404 Not Found [IP : .... 80]
I looked it up on the repo, it was there with a different name :
http://deb.debian.org/debian/pool/main/t/texlive-bin/texlive-binaries_2022.20220321.62855-5.1+deb12u1_amd64.deb
The error suggested that i run the command with --fix-missing
and run apt update
before, but it didnt work. So i tried to download the file and install it with sudo apt install ./texlive-binaries...+deb12u1_amd64.deb
. Then running sudo apt install texmaker
still did not found the package as it recognized the version is 5.1+deb12u1_amd64
and not 5.1
. I looked it up on google, did not find much, and moved on Overleaf.
But today, i ran apt update && apt upgrade
, and after i reboot i come to a tty. I am surprised. I found out i can't start gnome with startx
or sudo systemctl enable gdm3
. It turns out apt updated gnome-shell-common
to a deb12u1_amd64
version, and it broke the DE.
Now apt
lists all the gnome packets as installed automatically and not needed anymore, aswell as bolt, gir1, ibus, ...
I am confused, when i run apt install gdm3
it tells me gnome-shell
depends on gnome-shell-common = 43.4-1 but 43.6-1~deb12u1 will be installed. Impossible to fix the problem.
I looked up /etc/apt/sources.list
but everything seems fine :
deb http://deb.debian.org/debian bookworm flags
deb-src http://deb.debian.org/debian bookworm flags
deb http://security.debian.org/debian-security bookworm-security flags
deb-src http://security.debian.org/debian-security bookworm-security flags
deb http://deb.debian.org/debian bookworm-updates flags
deb-src http://deb.debian.org/debian bookworm-updates flags
where flags
is main non-free-firmware non-free contrib
. Also in source.list.d
I have vscodium.list
which contains deb [singed-by = /usr/share...gpg ] https://download.vscodium.con/debs vscodium main
apt policy gnome gnome-shell
returns
gnome:
installed : none
candidate : 1:43+1
version table :
1:43+1 500
500 http://deb.debian.org/debian bookworm/main amd64 Packages
gnome-shell:
installed : none
candidate :43.4-1
version table :
43.4-1 500
500 http://deb.debian.org/debian bookworm/main amd64 Packages
100 /var/lib/dpkg/status
Here is the content of apt update
:
Reached :1 http://deb.debian.org/debian bookworm InRelease
Reached :2 http://security.debian.org/debian-security bookworm-security InRelease
Reached :3 http://deb.debian.org/debian bookworm-updates InRelease
Reached :4 http://download.vscodium.com/debs vscodium InRelease
Reading list ... done
Constructing dependency tree ... done
Reading information status ... done
1 packet can be updated. Run apt list --upgradable to see it
Now I have a new update which is nvidia-installer-cleanup
and apt policy nvidia-installer=cleanup
is :
nvidia-installer-cleanup:
installed : 20220217+2
candidate : 20220217+3~deb12u1
version table :
20220217+3~deb12u1 500
500 http://deb.debian.org/debian bookworm/contrib amd64 Packages
20220217+2 100
100 /var/lib/dpkg/status
But i think i found the issue. I have a Brother HL-2135W printer that used to work on Debian 11. However, this time it did not work out of the box so when i tried to install it with the script found on Brother's support website, it was a 32 bit script : https://www.brother.fr/services-et-supports/hl-2135w/downloads
The script messed up libc6-i386
. I had to run dpkg -add-architecture i386
which messed up apt
. dpkg -l | grep i386
outputs
cupswrapperhl2130:i386
hl2130lpr:i386
so I uninstalled those two packages and run dpkg --remove-architecture i386
. But I still can't install gnome. There is a deeper issue with apt probably.
I run Debian 12 bookworm on an Dell Inspiron 5415 with Ryzen 5 5500U.
Thanks for your help.
themathsdude
(33 rep)
Sep 10, 2023, 02:21 PM
• Last activity: Aug 11, 2025, 10:14 PM
0
votes
1
answers
3928
views
read_passphrase being called on SSH key even though SSH key is not protected by password
I have a staging server and a production server, and I run identical Bitbucket Pipelines, where I send some commands over SSH. Unfortunately, my pipeline for the production always fails with: ``` Host key verification failed. ``` I've tried _everything_, folder permissions, recreating the keys, noth...
I have a staging server and a production server, and I run identical Bitbucket Pipelines, where I send some commands over SSH. Unfortunately, my pipeline for the production always fails with:
Host key verification failed.
I've tried _everything_, folder permissions, recreating the keys, nothing works.
Finally with adding -v
to my ssh
call, I think I'm a step closer, but still lost.
On my staging server, I see something like this:
debug1: Host '$STAGING_SERVER' is known and matches the RSA host key.
debug1: Found key in /root/.ssh/known_hosts:4
debug1: ssh_rsa_verify: signature correct
and the rest of the build follows flawlessly.
On my production server, however, I see the following:
debug1: Host '$PRODUCTION_SERVER' is known and matches the RSA host key.
debug1: Found key in /root/.ssh/known_hosts:5
debug1: read_passphrase: can't open /dev/tty: No such device or address
debug1: permanently_drop_suid: 0
ssh_askpass: exec(/usr/bin/ssh-askpass): No such file or directory
Host key verification failed.
So it would look like the key _is_ found on my production server, but for some reason on the production server read_passphrase
is being called. I've just created a new id_rsa and id_rsa.pub key, with _no_ password, so why the heck is my production server trying to call read_passphrase
? My ssh_config
and sshd_config
on both servers are identical - checked via diff
.
Another way of looking at it is that ssh_rsa_verify
is called immediately on the staging server, while on the production server read_passphrase
is called.
Any help here would be greatly appreciated, this is driving me crazy!
fullStackChris
(101 rep)
Dec 13, 2021, 02:18 PM
• Last activity: Aug 11, 2025, 10:03 PM
9
votes
1
answers
2736
views
gdm greeter configuration: Exclude all *except* for one specific user
I have Googled this one and tried so many combinations, with no success. I need the GDM login greeter to display one and only one username. In effect, what I need is something like this in **/etc/gdm/custom.conf**: [greeter] ExcludeAll=true Include=guest This does not work, however, because ExcludeA...
I have Googled this one and tried so many combinations, with no success.
I need the GDM login greeter to display one and only one username. In effect, what I need is something like this in **/etc/gdm/custom.conf**:
[greeter]
ExcludeAll=true
Include=guest
This does not work, however, because ExcludeAll is not a valid option. IncludeAll=false does nothing either. I've tried every combination that I can think of.
Despite being discouraged, I modified **/etc/gdm/gdm.schemas**, trying a variety of combinations similar to the above. No go.
I am aware of:
gconftool-2 --config-source xml:readwrite:/etc/gconf/gconf.xml.defaults --direct --type bool --set /apps/gdm/simple-greeter/disable_user_list true
but this is not an applicable solution, as it removes the user list completely. I need one specific username to appear.
The only practical solution I can find is to, upon user login, run a script which will append that username to the "Exclude" list in **/etc/gdm/custom.conf**. This is hacky, and not preferable.
This is for a public-use machine. People can log in with their LDAP accounts if they have them, or they can select "Guest" from the login screen. The people who log in with their LDAP accounts should NOT have their names visible on the login screen, but the "Guest" option must remain.
Using gnome 2.28.
CptSupermrkt
(1512 rep)
Apr 15, 2014, 08:01 PM
• Last activity: Aug 11, 2025, 09:02 PM
1
votes
1
answers
16817
views
JAVA_HOME should point to a JDK not a JRE
If anyone can help me with this, it would mean a lot as I've seen similarly answered questions for windows but not many or Linux. I am running I am running Linux mint 20.2 (Uma). I have a problem where trying to run my maven project, I get the error ``` The JAVA_HOME environment variable is not defi...
If anyone can help me with this, it would mean a lot as I've seen similarly answered questions for windows but not many or Linux. I am running I am running Linux mint 20.2 (Uma).
I have a problem where trying to run my maven project, I get the error
The JAVA_HOME environment variable is not defined correctly
This environment variable is needed to run this program
NB: JAVA_HOME should point to a JDK not a JRE
I have since fully uninstalled java and maven and set up JDK17 and the JAVA_HOME
$ echo $JAVA_HOME
/usr/lib/jvm/jdk-17.0.2
Along with setting the profile
$ grep JAVA_HOME /etc/profile
JAVA_HOME=/usr/lib/jvm/jdk-17.0.2
JRE_HOME=$JAVA_HOME/jre
PATH=$PATH:JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME
And .bashrc
$ grep JAVA_HOME ~/.bashrc
JAVA_HOME=/usr/lib/jvm/jdk-17.0.2
JRE_HOME=$JAVA_HOME/jre
PATH=$PATH:JAVA_HOME/bin:$JRE_HOME/bin
export JAVA_HOME
I also found a .sh
file in the /etc/profile.d/
that was redirecting JAVA_HOME to the old JDK and have since deleted it.
But even after all of this the problem pressies, I don't know if something is still redirecting JAVA_HOME to the old JDK or I didn't set it up correctly, I also don't know where to look if something is redirecting it or if I have an alias for
since I'm not adept to Linux fully and I haven't used to this system in a while to backtrack my changes.
If anyone has any input on how to solve this problem, it would be greatly appreciated. Thank you all in advance.
SaltySwan
(11 rep)
Feb 19, 2022, 04:39 PM
• Last activity: Aug 11, 2025, 08:03 PM
27
votes
4
answers
11819
views
Practical limit on the number of btrfs snapshots?
I am considering using btrfs on my data drive so that I can use [snapper](http://snapper.io/), or something like snapper, to take time based snapshots. I believe this will let me browse old versions of my data. This would be in addition to my current off site backup since a drive failure would wipe...
I am considering using btrfs on my data drive so that I can use [snapper](http://snapper.io/) , or something like snapper, to take time based snapshots. I believe this will let me browse old versions of my data. This would be in addition to my current off site backup since a drive failure would wipe out the data and the snapshots.
From my understanding btrfs snapshots do not take up much space (meta data and the blocks that have changed, plus maybe some overhead), so space doesn't seem to be a constraint.
If I have a million snapshots (e.g., a snapshot every minute for two years) would that cause havoc, assuming I have enough disk space for the data, the changed data, and the meta data?
If there is a practical limit on the number of snapshots, does it depend on the number of files and/or size of files?
StrongBad
(5491 rep)
Jul 2, 2014, 12:00 PM
• Last activity: Aug 11, 2025, 07:29 PM
4
votes
4
answers
476
views
Creating n folders with equal number of files from a large folder with all files
I have a large folder of data files, which I want to copy into subfolders to make a specified number of batches. Right now I count how many files there are and use that to make ranges, like so: ``` cd /dump batches=4 files=$(cat /data/samples.txt | wc -l) echo "$files $batches" for ((i=0; i<=batches...
I have a large folder of data files, which I want to copy into subfolders to make a specified number of batches.
Right now I count how many files there are and use that to make ranges, like so:
cd /dump
batches=4
files=$(cat /data/samples.txt | wc -l)
echo "$files $batches"
for ((i=0; i<=batches; i++))
do
mkdir -p merged_batches/batch$i
rm -f merged_batches/batch$i/*
ls merged/*.sorted.labeled.bam* |
head -n $(( $((files/batches)) * $((i+1)) * 2 )) |
tail -n $((2 * files/batches)) |
xargs -I {} cp {} merged_batches/batch$i
done
Is there a more convenient way to do this?
rubberduck
(53 rep)
Aug 7, 2025, 03:49 PM
• Last activity: Aug 11, 2025, 07:21 PM
1
votes
1
answers
2866
views
Reverse Proxy with Apache presenting blank page
I've got one Raspberry Pi 2 Model B running Deluge and Deluge Web UI 24/7. I set up a No-IP free host so I can access the Rasperry Pi to download some data I've stored in a 3TB disk. I am using Apache2 as the webserver but I am looking forward to change to a Go application I am creating myself. The...
I've got one Raspberry Pi 2 Model B running Deluge and Deluge Web UI 24/7. I set up a No-IP free host so I can access the Rasperry Pi to download some data I've stored in a 3TB disk.
I am using Apache2 as the webserver but I am looking forward to change to a Go application I am creating myself.
The WebUI Deluge listening port is **9090**.
I wanted to access Deluge WebUI without having to type :9090 in the end of the hostname (via /del would be ideal).
I read multiple questions on SO where the Reverse Proxies were mentioned. I quickly checked the official documentation.
The changes I've made to my configuration files are the following:
*/etc/apache2/sites-enabled/000-default.conf*
ProxyPass /del http://hostname:9090/
ProxyPassReverse /del http://hostname:9090/
I also tried **rewrite** in 000-default (but in different times)
RewriteEngine on
RewriteCond %{REQUEST_URI} /del [NC]
RewriteRule ^(.*)$ http://hostname:9090 [P]
Restarted Apache and the result is a blank page whenever I visit http://hostname/del **(via browser)**
fabiofcferreira
(121 rep)
Sep 2, 2017, 06:59 PM
• Last activity: Aug 11, 2025, 07:04 PM
0
votes
0
answers
31
views
Sendmail wont work for my ubuntu terminal server (Ubuntu 24.04.2)
I'm currently attempting (and failing) to set up an SMTP mail server on my Ubuntu server so I can recieve emails from the contact page of my php based website. I was planning to send these emails using phps built in mail() function. However, no matter what I try the email either never sends with no...
I'm currently attempting (and failing) to set up an SMTP mail server on my Ubuntu server so I can recieve emails from the contact page of my php based website. I was planning to send these emails using phps built in mail() function.
However, no matter what I try the email either never sends with no errors (in the case of using sendmail) or causes a client-side timeout (in the case of using postfix). If anyone can help me it'd be greatly appreciated!
I'm rather new to using SMTP related stuff so I don't really know what log files to attach so please ask me for them if needed. Thanks.
Edit: port 25 is forwarded
Hoax
(1 rep)
Aug 11, 2025, 06:16 PM
• Last activity: Aug 11, 2025, 06:32 PM
15
votes
2
answers
7924
views
How to disable suspend on close laptop lid on NixOS?
I'm using [NixOS](http://nixos.org), so the approach described in “https://unix.stackexchange.com/q/52643/11397”, editing `/etc/systemd/logind.conf`, won't work, as it is just a symlink to `/etc/static/systemd/logind.conf`, which itself is a symlink to a file in `/nix/store`. AFAIK, you shouldn't ed...
I'm using [NixOS](http://nixos.org) , so the approach described in “https://unix.stackexchange.com/q/52643/11397” , editing
/etc/systemd/logind.conf
, won't work, as it is just a symlink to /etc/static/systemd/logind.conf
, which itself is a symlink to a file in /nix/store
.
AFAIK, you shouldn't edit the *Nix store* directly. But the file in /nix/store
doesn't have write permissions anyway.
How do I disable laptop auto-suspension in a NixOS idiomatic way?
Mirzhan Irkegulov
(8818 rep)
Jan 25, 2016, 06:43 PM
• Last activity: Aug 11, 2025, 06:11 PM
1
votes
1
answers
1970
views
How to show all current ssh connected users on Linux?
Using GCP VM Instance, I'm connected via ssh, not serial port. When I type `w` or `who` or `finger` I get the following output: ``` $ w 08:46:18 up 41 min, 0 users, load average: 0.10, 0.07, 0.01 USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT $ who $ finger No one logged on. ``` I'm expecting to see my cu...
Using GCP VM Instance, I'm connected via ssh, not serial port. When I type
w
or who
or finger
I get the following output:
$ w
08:46:18 up 41 min, 0 users, load average: 0.10, 0.07, 0.01
USER TTY FROM LOGIN@ IDLE JCPU PCPU WHAT
$ who
$ finger No one logged on.
I'm expecting to see my current connected user, but this is not the case. I tried to connect as another user along mine and it showed, but not my primary user, either when he or the other runs the command.
> pstree -alus "$$"
systemd
└─sshd
└─sshd
└─sshd,Dédé
└─bash
└─bash
└─code-e170252f76 command-shell --cli-data-dir /home/Dédé/.vscode-server/cli --parent-process-id 234934 --on-port
└─sh /home/Dédé/.vscode-server/cli/servers/Stable-e170252f762678dec6ca2cc69aba1570769a5d39/server/bin/code-server --connection-token=remotessh --accept-server-license-terms --start-server --enable-remote-auto-shutdown --socket-path=/tmp/code-bd3d6d38-59de-47a1-8df7-54881cb666dd
└─node /home/Dédé/.vscode-server/cli/servers/Stable-e170252f762678dec6ca2cc69aba1570769a5d39/server/out/server-main.js --connection-token=remotessh --accept-server-license-terms --start-server --enable-remote-auto-shutdown --socket-path=/tmp/code-bd3d6d38-59de-47a1-8df7-54881cb666dd
└─node /home/Dédé/.vscode-server/cli/servers/Stable-e170252f762678dec6ca2cc69aba1570769a5d39/server/out/bootstrap-fork --type=ptyHost --logsPath /home/Dédé/.vscode-server/data/logs/20240504T173238
└─zsh -i
└─pstree -alus 271031
Dédé
(11 rep)
May 4, 2024, 10:57 AM
• Last activity: Aug 11, 2025, 06:08 PM
Showing page 10 of 20 total questions