In the old days I just modified /etc/inittab. Now, with systemd, it seems to start tty[1-6] automatically, how should I disable tty[4-6]?
Looks like there's only one systemd service file, and it use a %I to discern different tty sessions. I hope I don't need to remove that service, and create each [email protected] manually.
There is no real need to disable "extra" TTYs as under systemd gettys are generated on demand: see man systemd-getty-generator for details. Note that, by default, this automatic spawning is done for the VTs up to VT6 only (to mimic traditonal Linux systems).
As Lennart says in a blog post1:
In order to make things more efficient login prompts are now started on demand only. As you switch to the VTs the getty service is instantiated to [email protected], [email protected] and so on. Since we don't have to unconditionally start the getty processes anymore this allows us to save a bit of resources, and makes start-up a bit faster.
If you do wish to configure a specific number of gettys, you can, just modify logind.conf with the appropriate entry, in this example 3:
NAutoVTs=3
1. In fact the entire series of posts—currently numbering 18— systemd for Administrators, is well worth reading.
On Debian-based systems, there is a file that causes 5 extra getty's to be launched on startup if you've just built a server (without dbus service):
/lib/systemd/system/getty.target.wants/getty-static.service
In it, it says:
[Service]
Type=oneshot
ExecStart=/bin/systemctl --no-block start [email protected] [email protected] [email protected] [email protected] [email protected]
RemainAfterExit=true
Just deleting this file will stop the extra getty's from spawning. Feel free to shorten the list if you want to just spawn one extra getty (for 2 virt consoles). Note that you automatically get one on tty1 so you always have at least one virtual console.
See also: systemd-logind.service fails to start if dbus is missing
dpkg-divert first. But, there's also a systemd-native way to get it out of the way - run sudo systemctl mask getty-static.service and set up your own in /etc
Commented
Jul 9, 2017 at 13:23
masking an enabled service is noisy, it would be cleaner to create a unit with the same name in /etc to override it's contents. Use ExecStart=/bin/true if you desire to start zero static getty's.
Commented
Jul 30, 2017 at 12:30
sudo systemctl edit getty-static.service, which will create an override file that takes precedence over the /lib one
To disable gettys on particular TTYs 4-6 while possibly leaving 1-3 and 7-9 working, run:
for i in {4..6}; do
systemctl mask getty@tty${i}.service
done
mask creates symlink /etc/systemd/system/{name} -> /dev/null which effectively disables service. Attempt to run it via systemctl start will display error Failed to start NAME.service: Unit NAME.service is masked.
If you have A.service Wants=masked.service, then start A will succeed but also generate dependency start error in journal.
If you have B.service Requires=masked.service, then start B will also fail.
Yup, necroanswer. Cheers.
If you're going to mask as suggested above, make sure to use the right service:
If you've masked [email protected], you'll notice that switching TTYs with CTRL+ALT+FX will cause TTY to re-spawn.
This is because logind spawns getty via [email protected] (which links to [email protected]).
Hence why you're better off masking [email protected], e.g:
systemctl mask --now [email protected]
Reference: https://github.com/systemd/systemd/issues/8067#issuecomment-362902300
P.S. This solution only blocks logind from spawning TTYs meaning the logic is still active. Consider updating logind.conf to correctly disable VTs as seen above.
