Score:0

Ubuntu

Why root password exist if I can be root with sudo -s or sudo -i, it need only sudo password so?

pjk

10/30/22, 9:02 AM

sudo -i makes me root with sudo password

sudo -s, sudo su the same

su and su root need root password so it doesn't make sense to me, I can be root with only sudo password so why root password exist?

300

1 + 8

permissions

root

sudo

password

muru

10/30/22, 9:10 AM

By default there is no root password. Password access for the root user is disabled. Why did *you* set a root password?

pjk

10/30/22, 9:21 AM

So why it is possible to set root password?

paladin

10/30/22, 9:22 AM

A root password exists to be able to login as root. Usually the user root is handled with special care, often makes root the only user which is able to login into a system when a critical system error occurred. For example, when your `/home` directory is mounted on a different drive and this drive has a malfunction and Linux cannot mount it - this making every user unable to login, but the root user may still be able to login, cause his home directory is `/root`.

muru

10/30/22, 9:26 AM

@paladin the root user is a user, why shouldn't it be possible to set a password for them? It's perfectly possible to have a system without `sudo`, after all.

paladin

10/30/22, 9:26 AM

Also, when you want to change the home directory of a user, that user shouldn't be logged in. For example, user john wants to change his home directory, usually only a superuser may change a home directory. Doing sudo as user john won't help, because user john probably can't change his own home directory while logged in. So you would logout and login as root and change home directory of user john.

pjk

10/30/22, 9:30 AM

@paladin for example I have two users on my linux, peter and john. peter is in sudo and he is the owner of pc, john is also in sudo but peter don't want john to be able to use root account, so only peter knows root password but john still can be root because he is in sudo so he can just use sudo -i and that's it?

paladin

10/30/22, 10:47 AM

@pjk Whoever has sudo rights is also able to login into root account without password.

pjk

10/30/22, 10:51 AM

okay now I understand

Score:2

Ubuntu

vanadium

10/30/22, 10:03 AM

The answer to your question is quite simple. On Ubuntu, the root password does not exist. The root account is not enabled. Thus, the root user cannot login on a standard Ubuntu system.

Instead there is the sudo system where selected "normal" users can assume administrator priviledges. So if you want a terminal with root privileges, su will not work, because root is not active. However, you still can obtain such prompt with sudo -i, where you act as a privileged normal user, thus provide your own user password.

See here for a more elaborate discussion of sudo versus logging in to the root account. You will learn you can activate the root account. If you then ask "Why root password exist if I can be root with sudo -s or sudo -i, it need only sudo password so?", well, in this case it is you who created the contradictory situation. By default, that situation is not there.

0 + 5

pjk

10/30/22, 10:42 AM

Okay now I'm really close to understand it but I have one more question from my comment above, let me copy it: for example I have two users on my linux, peter and john. peter is in sudo and he is the owner of pc, john is also in sudo but peter don't want john to be able to use root account, so only peter knows root password but john still can be root because he is in sudo so he can just use sudo -i and that's it? In this situation john should't be in sudo group to avoid it?

paladin

10/30/22, 10:51 AM

`sudo su` will work, or just `sudo passwd` will enable any sudo-user to set a root-password.

vanadium

10/30/22, 10:58 AM

@pjk being administrator is a job of trust. If there are two root users that do not trust each other, then that has to be solved at the management level, not at the level of the operating system ;) So indeed, one can be taken away root privileges if need be (and if that person did not yet destroy the system yet).

vanadium

10/30/22, 10:59 AM

@paladin yes, root can do everything, including activating the root account. Being administrator is a job of trust.

Artur Meinild

10/30/22, 11:14 AM

Being able to have root access _without_ a password still have its advantages - for instance you can still login as root with SSH keys even if the password is not set. This is far more secure than using a password.

Elon Musk

I sit in a Tesla and translated this thread with Ai:

EN: Why root password exist if I can be root with sudo -s or sudo -i, it need only sudo password so?

TH: เหตุใดจึงมีรหัสผ่านรูทหากฉันสามารถรูทด้วย sudo -s หรือ sudo -i ต้องใช้รหัสผ่าน sudo เท่านั้น

RO: De ce există parola de root dacă pot fi root cu sudo -s sau sudo -i, este nevoie doar de parola sudo?

RU: Зачем существует пароль root, если я могу быть пользователем root с помощью sudo -s или sudo -i, для этого нужен только пароль sudo?

VI: Tại sao mật khẩu root tồn tại nếu tôi có thể root bằng sudo -s hoặc sudo -i, nó chỉ cần mật khẩu sudo như vậy?

Post an answer

Most people don’t grasp that asking a lot of questions unlocks learning and improves interpersonal bonding. In Alison’s studies, for example, though people could accurately recall how many questions had been asked in their conversations, they didn’t intuit the link between questions and liking. Across four studies, in which participants were engaged in conversations themselves or read transcripts of others’ conversations, people tended not to realize that question asking would influence—or had influenced—the level of amity between the conversationalists.