Stop Ctrl-Alt-Delete from rebooting - systemd here we come

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InitOrNot
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Stop Ctrl-Alt-Delete from rebooting - systemd here we come

Postby InitOrNot » 2015/08/29 18:58:42

I'm testing Centos 7 and for the life of me that I cannot get the system to NOT reboot when Ctrl-Alt-Delete is pressed on the console.

In the times of yore, it was enough to edit /etc/inittab and comment the relevant line there.

Now that systemd has taken over, the information about disabling this appears to be behind a paywal in RedHat's support web site: https://access.redhat.com/solutions/1123873

Other information which can be found on the Intertubes talks about running:

Code: Select all

# systemctl mask ctrl-alt-delete.target
# systemctl daemon-reload

However, I run those those commands and still Ctrl-Alt-Delete is rebooting my test system.

Anyone has any insights about that?

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AlanBartlett
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Re: Stop Ctrl-Alt-Delete from rebooting - systemd here we co

Postby AlanBartlett » 2015/08/29 20:23:37

. . . the information about disabling this appears to be behind a paywal in RedHat's support web site: https://access.redhat.com/solutions/1123873


All you need to do is to register and create a Red Hat account for yourself. Here follows the entire contents of the above Knowledge Base Solution --

Issue

* On RHEL7, /etc/init/control-alt-delete.override no more working to override key combination, how to disable the Ctrl-Alt-Del in RHEL7 ?
* How to disable Ctrl-Alt-Del in RHEL7 using GUI ?

Environment

* Red Hat Enterprise Linux 7
* systemd

Resolution

If requirement is to disable the ctrl + Alt + delete key combination, one need to mask a service. This is like disabling a service,

Run the following command:

# ln -sf /dev/null /etc/systemd/system/ctrl-alt-del.target

or

# systemctl mask ctrl-alt-del.target

NOTE: systemd will recognize units symlinked to /dev/null and show them as masked. If one try to send key combination, this will fail with following similar error.

Jul 9 02:33:43 rhel7test systemd: Failed to enqueue ctrl-alt-del.target job: Unit ctrl-alt-del.target is masked.

* However above steps will not disable ctrl + Alt + delete key combination, in GUI mode. To disable it in GUI change keyboard settings.

Navigate to Applications -> System Tools -> Settings -> Keyboard -> Shortcuts -> System
Set value of `Logout` as Disabled
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TrevorH
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Re: Stop Ctrl-Alt-Delete from rebooting - systemd here we co

Postby TrevorH » 2015/08/29 21:38:34

All you need to do is to register and create a Red Hat account for yourself.


Sorry, this does not work. What I get when I sign in is

A subscription is required for full access to the Red Hat Knowledgebase.
CentOS 5 died in March 2017 - migrate NOW!
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InitOrNot
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Re: Stop Ctrl-Alt-Delete from rebooting - systemd here we co

Postby InitOrNot » 2015/08/30 00:20:27

Thank you, AlanBartlett.

I can confirm these two command work fine disabling the Ctrl-Alt-Delete combo:

Code: Select all

systemctl mask ctrl-alt-del.target
systemctl daemon-reload


So there was a typo in the instructions about it in the (open access) github.com web page, and the restricted access RedHat page had the right information.

Systemd proponents claim it's documentation is great. Does anyone know whether this is documented in the systemd official documentation (source code is not documentation)?