How to Permanently Disable Linux Console Screen Blanking (VT Power Management)


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As a Linux system administrator, I've frequently encountered situations where headless servers blank their virtual console displays after inactivity, despite having no actual power-saving requirements. This behavior originates from the Linux kernel's VT (virtual terminal) power management system.

The console blanking is controlled by three key components:

1. Kernel parameters (consoleblank)
2. Terminal settings (setterm)
3. getty services (specific to login prompts)

The most reliable method is modifying the kernel boot parameters. Edit your bootloader configuration:

# For GRUB (most common)
sudo nano /etc/default/grub

# Find GRUB_CMDLINE_LINUX_DEFAULT and add:
GRUB_CMDLINE_LINUX_DEFAULT="consoleblank=0"

# Then update GRUB
sudo update-grub

For systems using systemd, create a service to run at startup:

# /etc/systemd/system/disable-console-blanking.service
[Unit]
Description=Disable console screen blanking
After=multi-user.target

[Service]
Type=oneshot
ExecStart=/usr/bin/setterm -blank 0 -powersave off -powerdown 0

[Install]
WantedBy=multi-user.target

Enable it with:

sudo systemctl enable --now disable-console-blanking.service

For login prompts, modify getty services. Create or edit:

# /etc/systemd/system/getty@tty1.service.d/noblink.conf
[Service]
ExecStartPre=/usr/bin/setterm -blank 0 -powersave off -powerdown 0

Check current settings with:

cat /sys/module/kernel/parameters/consoleblank
setterm -powerdown
setterm -blank

The first command should return 0, and the others should show '0' or 'off'.

  • Ubuntu/Debian: Works with GRUB method
  • RHEL/CentOS: May need additional getty service modifications
  • Arch Linux: Both methods work, but systemd approach preferred

Persistent console display is crucial for:

  • Headless server debugging
  • Industrial control systems
  • Kiosk mode applications
  • Long-running terminal sessions

If you're managing a headless Ubuntu server that occasionally needs local access, you've probably encountered the frustrating console blanking behavior. The screen goes dark after a few minutes of inactivity, requiring keyboard input to wake it up - not ideal when you're troubleshooting or just checking system status.

Linux console blanking is controlled by the kernel's VT (virtual terminal) subsystem. The blanking timeout is governed by:

# Current value can be checked with:
cat /sys/module/kernel/parameters/consoleblank

The most reliable system-wide approach is to modify kernel boot parameters:

  1. Edit the GRUB configuration: 
    sudo nano /etc/default/grub
  2. Find the line starting with GRUB_CMDLINE_LINUX_DEFAULT and add: 
    consoleblank=0
  3. Update GRUB: 
    sudo update-grub
  4. Reboot for changes to take effect

For systems using systemd, create a service to run at boot:

# /etc/systemd/system/disable-console-blanking.service
[Unit]
Description=Disable console blanking

[Service]
Type=oneshot
ExecStart=/usr/bin/setterm -blank 0 -powersave off -powerdown 0

[Install]
WantedBy=multi-user.target

Then enable it:

sudo systemctl enable --now disable-console-blanking.service

After implementing either solution, verify with:

cat /sys/module/kernel/parameters/consoleblank
# Should return 0

Or check current terminal settings:

setterm -term linux -dump