The sys admin's daily grind: sudoers

Charly's Column – sudoersn

Article from Issue 221/2019
Author(s):

"I've seen penguins that can type better than that." If you give sudo the wrong password, you deserve to be shouted at, says sys admin columnist Charly. He is not exempt from the insult and sees it as an opportunity to raise sudoing awareness.

If you work with and on Linux, you are likely to type sudo regularly to execute programs with another user's privileges – typically the superuser's. sudo will then understandably ask for the appropriate password. In times when my fingers refuse to obey me and I enter the secret password wrong three times in succession, sudo rejects my request to escalate. Okay, if you fail to type the password correctly despite having had three attempts, maybe you shouldn't be messing around on the system with root privileges. So far, so good, but free software can surely offer more than that!

sudo visudo

sudo looks for its default settings in the /etc/sudoers file. You can't just open it with an editor; instead, you need to use the visudo command – assuming you're root. (If I'm on the road as a user, I have to type sudo visudo, which strangely makes me laugh.) At the beginning of the file are some lines that start with Defaults. You need to add two lines here (Figure 1):

Defaults insults
Defaults passwd_tries=5

[...]

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