How to check root partition with fsck?

I installed Linux Mint 12 KDE, and I would like to check the root partition for any errors.

How do I check the root partition with fsck at boot time?

asked Mar 15, 2012 at 21:26

sudo touch /forcefsck

answered Mar 16, 2012 at 2:42

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You can use shutdown command for this too.

shutdown -rF now

The -F flag means ‘force fsck’.
This only creates an advisory file /forcefsck which can be tested by the system when it comes up again. The boot rc file can test if this file is present, and decide to run fsck(1) with a special `force’ flag so that even properly unmounted file systems get checked. After that, the boot process should remove /forcefsck.

answered Jun 4, 2012 at 17:44

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Here is another way to do this:

tune2fs -C 2 -c 1 /dev/THEDEVTHATROOTIS

then the filesystem will be checked, and once all is good you should do

tune2fs -c 60 /dev/THEDEVTHATROOTIS

I have assumed that the max-mount-count was set to 60, you should find out before issuing the first command with

answered Apr 7, 2012 at 18:54

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On my systems (several x86 notebooks and a Banana Pi Pro), saying sudo shutdown now brings me to runlevel 1 (aka maintenance mode) where I can safely check my root FS:

mount -o remount,ro /dev/rootpartition
fsck /dev/rootpartition
reboot

There’s no need to alter /etc/fstab to do this, and I have the opportunity to run fsck with whatever options that may be needed to fix a tricky case.

Note: /forcefsck and tune2fs tricks work on x86, but not on Banana Pi.

answered Sep 16, 2015 at 18:06

Dmitry Grigoryev

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If you are on a Raspberry pi and you find yourself in emergency mode, you can in fact unmount the root partition and still use fsck

(login as root)
mount -o remount,ro /
fsck
reboot

answered Apr 7, 2019 at 21:16

On modern linux systems the answers above (with forcefsck) don’t work. You have to do it manually:

1. Put your root partition into read-only mode by modifying the faulty partition’s line on /etc/fstab (but remember your old settings):

   UUID=fd1d0fad-3a4c-457f-9b5e-eed021cce3d1 / ext4 remount,ro 1 1

3. Switch to runlevel 1 just to minimize the amount of interfering processes:

   init 1

4. Fix your file system (replace /dev/sda2 with your partition’s device), which should now work because the root partition is in read only:

   fsck /dev/sda2

5. Reboot. (On my Fedora 21 system I had to change to runlevel 1 during boot with Grub2, because otherwise the system was stuck due to not being able to write on the root-partition)

6. Make your root file system readable/writable:

   mount -o remount,rw /dev/sda2

7. Restore your /etc/fstab to its original state.

answered Jul 28, 2015 at 0:48

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whoami

echo $EUID

if (( $EUID == 0 )); then echo "You are root" // Do commands if user is root
else echo "You are normal user" // Do command if user not is root
fi

How do I know if user is root or sudo?

Bash script to check if a specific user is present in etc passwd

Images related to the topicBash script to check if a specific user is present in etc passwd

How do I find my root username in Linux?

1. su command – Run a command with substitute user and group ID in Linux.
2. sudo command – Execute a command as another user on Linux.

How do you check what permissions a user has in Linux?

1. ls -l. Then you will see the file’s permissions, like the following: …
2. chmod o+w section.txt. …
3. chmod u+x section.txt. …
4. chmod u-x section.txt. …
5. chmod 777 section.txt. …
6. chmod 765 section.txt. …
7. sudo useradd testuser. …
8. uid=1007(testuser) gid=1009(testuser) groups=1009(testuser)

What is root in terminal?

See some more details on the topic bash check if user is root here

How do I check if I have root access? – Unix Stack Exchange

Yes. If you are able to use sudo to run any command (for example passwd to change the root password), you definitely have root access.

Check the bash shell script is being run by root or not – nixCraft

Check if user is root/sudo before running a script – The Electric …

How do I check if a user has root access in Linux? – OS Today

What is the user ID of root?

Shell Script Check If Directory Exists – Folder – Linux – BASH – tutorial

Images related to the topicShell Script Check If Directory Exists – Folder – Linux – BASH – tutorial

How do I access root?

In most versions of Android, that goes like this: Head to Settings, tap Security, scroll down to Unknown Sources and toggle the switch to the on position. Now you can install KingoRoot. Then run the app, tap One Click Root, and cross your fingers. If all goes well, your device should be rooted within about 60 seconds.

How do you check user permissions in Unix?

To view the permissions for all files in a directory, use the ls command with the -la options. Add other options as desired; for help, see List the files in a directory in Unix. In the output example above, the first character in each line indicates whether the listed object is a file or a directory.

How do I give a user root access in Linux?

1. To add a user to root using usermod, we have to run the following command in the terminal. …
2. To add an existing user to the root group, follow the following command: usermod -g 0 -o user. …
3. useradd command can be used to create a new user or update default new user information. …
4. Example:

What does chmod 777 mean?

777 – all can read/write/execute (full access). 755 – owner can read/write/execute, group/others can read/execute. 644 – owner can read/write, group/others can read only.

How do you find if a user has permissions on a particular file?

Check Permissions in Command-Line with Ls Command

If you prefer using the command line, you can easily find a file’s permission settings with the ls command, used to list information about files/directories. You can also add the –l option to the command to see the information in the long list format.

Is a root user in Linux?

Complete Shell Scripting | Run shell script with root user or with sudo privilage

Images related to the topicComplete Shell Scripting | Run shell script with root user or with sudo privilage

How do I login as root in terminal?

Part 1 of 5:

• linux bash check if user is root
• bash check if variable is set
• how to check if user is superuser
• bash script check if user is root
• bash root directory
• bash script run as root
• bash if
• check root users
• bash if else
• ubuntu check if user is root
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• bash check if file exists
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Information related to the topic bash check if user is root

$ sudo -ll
Matching Defaults entries for user1 on this host: env_reset, secure_path=/usr/local/sbin\:/usr/local/bin\:/usr/sbin\:/usr/bin\:/sbin\:/bin
User user1 may run the following commands on this host:
Sudoers entry: RunAsUsers: ALL RunAsGroups: ALL Commands: ALL

$ sudo -l ls
/bin/ls

if (i_am_root) do_privileged_op(); else print_error();

uid_t uid=getuid(), euid=geteuid();
if (uid<0 || uid!=euid) { /* We might have elevated privileges beyond that of the user who invoked * the program, due to suid bit. Be very careful about trusting any data! */
} else { /* Anything goes. */
}

if(geteuid() != 0)
{ // Tell user to run app as root, then exit.
}

#include #include int main()
{
int a;
a=getuid();
//or you can use a=geteuid();
//euid is effective user id and uid is user id
// both euid and uid are zero when you are root user
if (a==0){
printf("you are root user");
//so you can do what`enter code here`ever `enter code here` you want as root user
}
else
printf("please run the script as root user !");
return 0;
} 

#include #include int main() { auto me = getuid(); auto myprivs = geteuid(); if (me == myprivs) std::cout << "Running as self\n"; else std::cout << "Running as somebody else\n";
}

#include  // getuid
#include  // printf
int main()
{ if (getuid()) printf("%s", "You are not root!\n"); else printf("%s", "OK, you are root.\n"); return 0;
}

How can a script check if it’s being run as root?

I’m writing a simple bash script, but I need it to check whether it’s being run as root or not. I know there’s probably a very simple way to do that, but I have no idea how.

Just to be clear:

What’s a simple way to write a script

foo.sh

, so that the command

./foo.sh

outputs

0

, and the command

sudo ./foo.sh

outputs

1

?

#!/bin/bash
if [[ $EUID -ne 0 ]]; then echo "This script must be run as root" exit 1
fi

The only reliable program to check whether the account is logged in as root, or not:

id -u

Tests

rootx
root2

Logged in as

root2

, gives the next results:

• 
whoami

  :
  
rootx

• 
echo $USER

  :
  
root2

  (this returns an empty string if the program was started in an empty environment, e.g.
  
env -i sh -c 'echo $USER'

  )
• 
id -u

  :
  
0

  As you can see, the other programs failed in this check, only
  
id -u

  passed.

The updated script would looks like this:

#!/bin/bash
if ! [ $(id -u) = 0 ]; then echo "I am not root!" exit 1
fi

#!/bin/bash
if [[ $EUID -ne 0 ]]; then echo "You must be root to do this." 1>&2 exit 100
fi

#!/bin/bash
if (( EUID != 0 )); then echo "You must be root to do this." 1>&2 exit 100
fi

#!/bin/bash
if [ `whoami` != 'root' ] then echo "You must be root to do this." exit
fi
...

if [ $USER != 'root' ]

How to know if I have root privileges in Linux Shell terminal

How to know if I am a root user in Linux

Linux Command Line (13) The Root User

Checking for root user in sh and bash [duplicate]

The problem is, between bash and sh, the environment variables are different:

• bash -> $EUID (all caps)
• sh -> $euid (all lower)

I would check the value of

id -u

, which is specified to:

Perhaps like this:

if [ $(id -u) -eq 0 ]
then : root
else : not root
fi

How do I determine if a shell script is running with root permissions?

I’ve got a script I want to require be run with su privileges, but the interesting scripted command that will fail comes very late in the script, so I’d like a clean test up front to determine if the scrip will fail without SU capabilities.

What is a good way to do this for bash, sh, and/or csh?

#!/usr/bin/env bash
# (Use #!/bin/sh for sh)
if [ `id -u` = 0 ] ; then echo "I AM ROOT, HEAR ME ROAR"
fi

#!/bin/csh
if ( `id -u` == "0" ) then echo "I AM ROOT, HEAR ME ROAR"
endif

You might add something like that at the beginning of your script:

#!/bin/sh
ROOTUID="0"
if [ "$(id -u)" -ne "$ROOTUID" ] ; then echo "This script must be executed with root privileges." exit 1
fi