75.6 SUDO No Password
20201228 Cloud installations of Ubuntu generally provide
for the user created during installation to have sudo
access without a password, by default. In fact this user generally
does not have a password either. This is convenient for the system
administrator and is considered a safe practice when access to the
server is limited to using ssh public keys. The user with these
privileges (the username created at installation time) will be named
in the file
# Created by cloud-init v. 20.1-10-g71782edf-0ubuntu5 on Mon, 17 Aug 2020 04:58:35 +0000 # User rules for kayon kayon ALL=(ALL) NOPASSWD:ALL
To grant other users this password-less access to sudo, use visudo to add this rule:
$ sudo visudo # User alias specification kt ALL=(ALL) NOPASSWD:ALL
I’ve not been able to determine why, but this does not work to allow
kt access without a password. If instead the file
/etc/sudoers.d/90-cloud-init-users is edited to replace
kt it does work. Note that on install
this file does not have write permission and so that will need to be
modified in order to change it. However, there is probably good
reason it is not writable.
$ sudo ls -l /etc/sudoers.d/90-cloud-init-users -r--r----- 1 root root 144 Nov 17 09:28 /etc/sudoers.d/90-cloud-init-users $ sudo chmod u+w /etc/sudoers.d/90-cloud-init-users $ sudo editor /etc/sudoers.d/90-cloud-init-users
Change the username to that of the privileged user, save the file and exit the editor.
The change takes effect immediately so login to that priviledged user’s account and continue:
$ sudo chmod u-w /etc/sudoers.d/90-cloud-init-users $ sudo -K
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