Questions tagged [uid]

The tag has no usage guidance.

Filter by
Sorted by
Tagged with
0 votes
2 answers
33 views

Is it possible to create multiple users on Linux with the same UID and GID, especially UID and GID 0?

The ArchWiki - rsnapshot page mentions creating multiple users with uid and gid set to 0 as a means of creating users that login remotely to perform backups. One thing you can do to mitigate the ...
vfclists's user avatar
  • 7,531
0 votes
2 answers
58 views

What should the group of a user in Linux be to access samba?

I have a friend who works at a business where the IT guy has passed away and I am trying to help them until they can hire someone else. It is a workgroup networked with a Linux server. They recently ...
Michael Welch's user avatar
0 votes
1 answer
141 views

How to make command `id` print different real and effective UID in Ubuntu

The info page of command id states that it will output the effective user ID if different from the real user ID. I have been trying to achieve that somehow, running the command with the Bash shell as ...
gambarimas87's user avatar
1 vote
0 answers
147 views

What causes `newuidmap` to be dissallowed in new user namespace?

I expected uid=0(root) gid=0(root) groups=0(root) to be the output of both $ rootlesskit id $ unshare -U bash -c 'newuidmap $$ 0 '"$(id -u)"' 1; id' however the somewhat more verbose -x ...
humanityANDpeace's user avatar
0 votes
0 answers
121 views

What is everybody user & group on Android and why there's no everybody user & group on Linux?

In Root Explorer I have the option 9997-everybody and 9999-nobody. If I change the owner of any file to everybody:everybody, will it be fully editable by all users? This user does not exist on the ...
Mai Ngọc Vinh's user avatar
0 votes
1 answer
211 views

Which UID/GID is free for new package

After reading https://unix.stackexchange.com/a/222376/246754 How rpm ensure that no uid/gid clash with each other ? What I am looking is similar to https://github.com/NixOS/nixpkgs/blob/...
Et7f3XIV's user avatar
  • 103
1 vote
1 answer
183 views

Why does the UID of /dev/tty1, tty2 change preiodically on Ubuntu 22.04

I am on Ubuntu 22.04. I noticed that the tty which runs the Ubuntu GUI periodically changes from tty2, to tty3, what is the reason for this? I also noticed other UID changes, for instance tty1 has ...
user avatar
0 votes
2 answers
107 views

Loop over users problem

I am struggling with a loop over users id, i want to list all the users in /etc/passwd whose id are greater than 999, it doesn't recognize my if .. fi sentence and it is important to say that I am ...
Sebastian Rojas's user avatar
-1 votes
1 answer
452 views

passwd source code

I am trying to look at the source code of the passwd and gpasswd programs. These tools check the effective UID set to zero to complete execution successfully. But I am a noob to C and couldn't find ...
Tomas 's user avatar
  • 141
11 votes
2 answers
3k views

Is there a file besides /etc/passwd that contains/defines my UID?

Trying to learn about UIDs and GIDs. Various online reading led me to believe that my UID is saved in /etc/passwd, but this doesn't appear to be the case on a server where I work: $ whoami user1 $ cat ...
StoneThrow's user avatar
  • 1,717
0 votes
3 answers
770 views

Which command should I use as root to spawn a process with overridden numeric uid/gid/groups?

Which command (available in distro repositories) should I use start a shell with specified numeric uid, gid and groups? Typically su is used to change from root to other user, but it tries to look up ...
Vi.'s user avatar
  • 5,698
0 votes
0 answers
643 views

undo usermod for root?

At some point where I wanted to do sudo usermod -v 1000-1000 USER sudo usermod -w 1000-1000 USER I accidentally applied both these commands to root. According to the documentation I can undo these ...
alle_meije's user avatar
2 votes
0 answers
358 views

Can't change gid with mount

I'm mounting a MicroSD card using this command: mount -t vfat -o uid=1001,gid=1001 /dev/mmcblk0p1 /media/sd After that, I issue a mount command and notice that gid=100 in the listing. I've tried ...
Eric's user avatar
  • 21
0 votes
1 answer
1k views

Is there any file/directory permission effect if change uid or gid on Linux?

If group and user's settings are group name: group1 gid: 2000 user name: user1 uid: 2000 Some directory's permission is Directory: /application Owner: user1 Group: group1 When change the gid and ...
Miantian's user avatar
  • 103
2 votes
0 answers
310 views

Sync LDAP groups and UIDs with Active Directory

Currently, our organization has a working OpenLDAP server that we use to login to our Linux environments. However, due to the increase in Windows devices, the higher-ups have decided to migrate to an ...
Qiangong2's user avatar
  • 121
1 vote
2 answers
873 views

Add another root with different uid and name

I know that root has full admin rights thanks to something in the kernel that gives to uid 0 those rights. I think that also the name "root" is defined in the kernel, right? And the location ...
Scorpion's user avatar
  • 757
1 vote
0 answers
216 views

One particular UID causes very slow performance

One of our accounts on a CentOS 7 machine experienced very slow disk read/write.  I started looking into this because the 1007 user on this machine ran wget much slower than other user/machines. id ...
John Jiang's user avatar
1 vote
1 answer
2k views

Attempting to get root UID from root EUID

So here is the situation. I have a hypothetical system with 2 users - 'user1' and 'root'. The user 'user1' is just a normal non-sudoer user with uid=1000, and the root, is just a normal root user with ...
Bl4ckC4t's user avatar
2 votes
1 answer
1k views

Can not execute sudo commands on aws ec2 instance ssh http all ports are off

recently I have been facing a serious issue on one of my servers. While accessing my server with solar putty on windows I got error accessing the server message on the response. So I tried from my ...
MD Nasirul Islam's user avatar
4 votes
1 answer
3k views

Trying to change uid to user, but says it already exists

I'm trying to change the UID of user ec2-user to 500, when I try the following command getting the error UID already exists. sudo usermod -u 500 ec2-user usermod: UID '500' already exists I'm doing a ...
Diego's user avatar
  • 141
0 votes
1 answer
952 views

Problem in gaining uid of the system caller in a system call LKM using cred.h

I was trying to get the uid of the process runner which is calling my syscall. I use linux/cred.h and its macro called current_uid() . The problem is that it returns a type which is unknown for me, ...
zbx0310's user avatar
  • 47
0 votes
1 answer
1k views

Allow ssh access for users with certain UID from certain IP's

I need to allow ssh access to all users, but if the UID is between 6000 and 6500 I need to check if the IP where the ssh is coming from is in the file /etc/remote-hosts. /etc/remote-hosts 1.2.3.4 5.6....
Rafael Moreira's user avatar
1 vote
0 answers
132 views

Start NFS server without UID and GID of Unix directory

I'm trying to set up a NFS Server on Windows to map a folder of a Unix system connected to the same network. The second step in the tutorial How to set up a free NFS server on Windows 10 (sections 4 ...
Vlad Iordache's user avatar
0 votes
2 answers
230 views

How can I test that a buildah script is run under buildah-unshare?

If I have a script that uses buildah mount. I use the same way the docs specify, mnt=$(buildah mount $ctr) If I invoke my script sh ./build.sh, I get cannot mount using driver overlay in rootless ...
Evan Carroll's user avatar
  • 30.9k
0 votes
0 answers
45 views

Prevent deb installation from creating new accounts

We are configuring a variety of servers programmatically, and we periodically need to be able to migrate volumes from one server to another. After migrating a volume, we are currently executing chown ...
Brandon's user avatar
  • 101
2 votes
2 answers
923 views

Switch to other user instead root while using sudo

I would like to redirect (switch) one execution to other user instead root while using sudo. Example: sudo startup.sh will execute the startup.sh as root, but what is needed is for it to be executed ...
maddy's user avatar
  • 21
5 votes
2 answers
327 views

an executable emits “pax archive volume change required”

I'm trying to run a ./configure executable for a software (I'm doing it through a remote Linux machine using PuTTY) and at some point it says: ATTENTION! pax archive volume change required. Ready for ...
user422335's user avatar
2 votes
0 answers
1k views

Changing minimum UID to SSH into server

Our Linux HPC server (RHEL 7) only accepts logins to interactive sessions from users with UID >= 1000. However, some of our users have UID lower than that because their usernames were created on a ...
Waldir Leoncio's user avatar
1 vote
1 answer
2k views

Changing the User UID of a User with No Name

If a user has an UID but no name, ie: $ whoami whoami: cannot find name for user ID 1001 $ id uid=1001 gid=0(root) groups=0(root) is it possible to change the UID but still leave the user name ...
Athena Wisdom's user avatar
0 votes
0 answers
19 views

Perl resets the EUID only when executing multiple commands through `env - /usr/bin/perl -e 'system("...")'`? [duplicate]

I was playing around with setuid perl for command execution (insecure). I learned from another question, that env - /usr/bin/perl -e 'system("...")' doesn't reset the EUID to RUID, like it's the ...
Shuzheng's user avatar
  • 4,431
0 votes
1 answer
5k views

Proxmox LXC storage share, permission problems

I'm totally new in these enviroments but I'm trying to learn. I installed proxmox on a single SSD, then attached one HDD(/dev/sdb) to the system for media storage. The basic idea was to create one ...
toma3757's user avatar
1 vote
1 answer
266 views

POSIX compliant way of writing conditional operators [duplicate]

In bash you can do if [ $(echo $UID) != 0 ] then echo "Run as root" exit fi This returns an error message when I run the script with dash or other POSIX-compliant shells. How do you do this ...
opfez's user avatar
  • 13
1 vote
0 answers
118 views

Solaris 11.4 RBAC works for vim, not for su

I want to access some commands as root, for a normal user. I create the profile profiles -p "privileged" set desc="privileged profile" add cmd=/bin/su set euid=0 end commit exit Then I add profile ...
elbarna's user avatar
  • 12.7k
2 votes
1 answer
329 views

Why do processes have UID/GID?

What's the point of UID and GID in processes' parameters? There is EUID, RUID, SUID (and for Linux FSUID) that determine process privileges. I can't think what's the use of UID/GID in such scenario. ...
SantaXL's user avatar
  • 365
1 vote
1 answer
1k views

change UID and GID file attributes on read only file system with mount [duplicate]

I have some file image of filesystem, and I want mount it with parameter changing files and directories UID and GID. I cannot change its parameters, because it is read-only filesystem. I found some ...
Znik's user avatar
  • 649
6 votes
2 answers
3k views

Questions about the saved user ID

As far as I understood the different user IDs are as follows (from the perspective of a process): real user ID: the user ID that owns the process effective user ID: the user ID which determines what ...
Chris's user avatar
  • 185
0 votes
0 answers
423 views

UID/GID mapping for external storage across different POSIX systems [duplicate]

I have access to multiple POSIX desktops where my personal user account has different UID/GID. I use an ext4 formatted portable SSD, which is great for my work, except for the permissioning issues ...
Yuv's user avatar
  • 101
2 votes
1 answer
12k views

Get users with UID >= 1000 from /etc/passwd

I am trying to get usernames from /etc/passwd if UID equal/greater than 1000 using a for loop. The below simple bash script works but prints the username twice for some reason. #!/bin/bash for ...
Kumar's user avatar
  • 23
1 vote
0 answers
1k views

Specify UID/GID for NFS mount (CentOS 7)

I have two servers svrA and svrB (both CentOS 7), where svrA is a turn-key system so I cannot change anything on it, and svrB is the one I am working on. svrA contains log files I need to transfer to ...
garreth33's user avatar
0 votes
1 answer
90 views

Predictable UIDs of users created in the process of portage package installation

Adding users is specified in portage ebuild files using the enewuser function. Some ebuilds call this function with a specific UID (second argument), others either don't provide the argument or ...
Simon Fromme's user avatar
3 votes
1 answer
1k views

When did user accounts using UIDs above 1000 become normal? And why?

We have a really old NIS domain which is mapping some user accounts to UIDs less than 1000. I'm wondering when did using UIDs greater than or equal to 1000 for human users become 'standard', why did ...
Samuel Harmer's user avatar
2 votes
1 answer
334 views

ID inheritance – Which IDs?

I'm learning UNIX file permissions / ID inheritance and would like to clarify something: I have this list of permissions, users, groups and files: -rwxr-xr-x userA A foo -rw-rwsr-x userB B bar ...
hashsaltpepper's user avatar
3 votes
1 answer
366 views

How essential are usernames ( compared to uids )?

Background: I recently read about a freedesktop.org-bug which allowed executing any systemctl command for uid > INT_MAX. Thus I ran: root@host$> useradd -u 4000000000 largeuiduser root@host$&...
humanityANDpeace's user avatar
0 votes
0 answers
190 views

Is there a recommended way to access files owned by a non-user UID?

Suppose a multiboot computer on which two GNU/Linux distributions are installed, each with its own user(s). Say those users don't share the same UID over the two systems. Now one needs to access the ...
Skippy le Grand Gourou's user avatar
5 votes
1 answer
24k views

Assignment of UID and GID from Active Directory

My CentOS 7 machine has successfully joined a domain FOOBAR (as verified by realm list) and here's the information about an user coming from the AD (non-local): [root@centos7 ~]# id jdoe@FOOBAR....
dr_'s user avatar
  • 29.7k
1 vote
1 answer
2k views

Mapping user to filesystem user when UID's mismatch?

Say I have a user named user with UID 1001 on one system and the same user (named user) with another UID, let's say 1002. If I unplug the disk drive from the second system and plug it into the first, ...
Petr Skocik's user avatar
  • 28.9k
0 votes
1 answer
464 views

How to create multiple IDs with same UID in AIX ? How to change UID of IDs in AIX?

How to create multiple IDs with same UID in AIX ? How to change UID of IDs in AIX ?
Rahul Raj's user avatar
6 votes
1 answer
2k views

First process in a new Linux user namespace needs to call setuid()?

I'm learning about Linux user namespaces and I'm observing a strange behavior which isn't completely clear to me. I've created a range of UIDs in initial user namespaces to which I can map UIDs in ...
woky's user avatar
  • 432
0 votes
3 answers
258 views

Shell script example to stop execution of all processes with a certain UID? [duplicate]

I can't seem to find any examples on the internet for this particular task.
Amalia's user avatar
  • 1
2 votes
1 answer
460 views

How does sudo achieve changing the privileges of a process?

From man sudo When sudo executes a command, the security policy specifies the execution environment for the command. Typically, the real and effective user and group and IDs are set to match ...
Tim's user avatar
  • 102k