Sudo: Kein TTY vorhanden und kein »askpass«-Programm angegeben

[hmerk (Hans-Jörg Merk)]

Your Buster installation has configured user pi to not ask for a password. This can be done in openHABian too, but needs deeper linux / visudo knowledge…
Google has a lot of information on how to do this.

[Wolfgang_S]

@sjheinz

What is to do to make “sudo” not asking for a passwort in openhabian release?

that you already did.
Remember:

• user openhab needs to be member of the sudo group
• check if it is a member of sudo is to run: id openhab
• reply to that command will show the groups the user is a member of ( see earlier posts )

@sjheinz

In my “normal” raspian “Buster” installation you can use sudo as user pi without been asked for a password.

see the above command id that show the same output ( group member sudo ) for the user pi

As you write in case you put the command into a comment the reason must be tty output and not the askpass ( I assume ). You have a second sudo command active - correct ? If that is the case and although the command is active the reason for the warning/error message must be the STDOUT/STDERR output.

Try:

sudo ip neigh flush dev eth0 ${IP} >/dev/null 2>&1

[sjheinz (stefan heinz)]

Hi,
I changed /etc/sudoers with visudo and reboot the system.

openhabian@openHABianDevice:~ $ sudo more /etc/sudoers
[sudo] Passwort für openhabian:
#
# This file MUST be edited with the 'visudo' command as root.
#
# Please consider adding local content in /etc/sudoers.d/ instead of
# directly modifying this file.
#
# See the man page for details on how to write a sudoers file.
#
Defaults        env_reset
Defaults        mail_badpass
Defaults        secure_path="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"

# Host alias specification

# User alias specification

# Cmnd alias specification

# User privilege specification
root    ALL=(ALL:ALL) ALL

# Allow members of group sudo to execute any command
%sudo   ALL=(ALL:ALL) ALL

# See sudoers(5) for more information on "#include" directives:

#includedir /etc/sudoers.d

openhab ALL=(ALL:ALL) ALL
openhabian      ALL=(ALL:ALL) ALL

As you can see I add at the end of the file the users “openhab” and “openhabian”
So It is descripted for example here:

How To Add a User to Sudoers On Debian 10 Buster – devconnected

And you can see that after the “sudo more /et…” command that the system ask for password…
So my question is there anything else to do in openhabain to bring sudo to work without asking for passwords.

Thank you
Cheers
Stef

[sjheinz (stefan heinz)]

Hi Wolfgang,

Using:

sudo ip neigh flush dev eth0 ${IP} >/dev/null 2>&1

the wrning is gone
Thank you very much
Cheers
Stef

[Wolfgang_S]

This

@sjheinz

openhab ALL=(ALL:ALL) ALL
openhabian      ALL=(ALL:ALL) ALL

is redundant as you already have

@sjheinz

# Allow members of group sudo to execute any command
%sudo   ALL=(ALL:ALL) ALL

and according to post Sudo: Kein TTY vorhanden und kein »askpass«-Programm angegeben - #11 by sjheinz openhab was already a member of sudoers at that time. openhabian is a member of sudoers by default.

Of course this redundancy doesn’t matter and it works.

[hmerk (Hans-Jörg Merk)]

Check the following please, you need to add NOPASSWD
https://kofler.info/sudo-ohne-passwort/

[sjheinz (stefan heinz)]

Hi,

yes that is the solution adding “NOPASSWD:” - Thank you very much.

For all readers:

the solution in generell to avoid any warning using scriupts in openhab underneath /etc/openhab2/scripts/ is adding:

openhab ALL=(ALL:ALL) NOPASSWD: ALL
openhabian      ALL=(ALL:ALL) NOPASSWD: ALL

in /etc/sudoers using “sudo visudo”

So finally I ask myself why is this not integrated in openhabain releases to avoid “stupid” typing passwords for openhabian user because you´ll often instructed to use sudo … in several community articles. Maybe this is to avoid errors having a break while typing the password. But in my eyes this works for only for 3 till 5 starting events. Later also the effect to memorize openhabians password is gone also

And secound in m eyes openhab has to be a memeber of sudoers that avoird any warning when using scripts as we can learn from this discussion.

Cheers and many thanks to hmerk and Wolfgang_S for very kindly and fast and very good support
Cheers
Stef
Maybe a maintainer updates new openhabian images with this work around.

[rossko57]

executeCommandLine() is considered a tool for advanced users.
Disabling password protection for possibly no purpose is not a good security practice.

[sjheinz (stefan heinz)]

Hi rossko57,

if anybody is able to get in the system this guy is for shure able to use visudo command as well as all other commands without using/editing sudoers file!
sometimes the highly security argument is in my eyes beyond the borders.

Cheers
Stef