OS: Ubunutu 14.04
In the /home/ubuntu directory, I created the following script:
echo >000-default.conf.test
sudo cp 000-default.conf.test /etc/apache2/sites-enabled/000-default.conf.test
sudo echo 'this is a test'>> /etc/apache2/sites-enabled/000-default.conf.test
sudo cat /etc/apache2/sites-enabled/000-default.conf.test
When I run the script, I get the following error message:
./test_f.sh: line 3: /etc/apache2/sites-enabled/000-default.conf.test: Permission denied
Any ideas why I am getting the error message when the copy operation is succeeding?
Sure.
Redirecting output into files is done by the shell, not by sudo. So if the shell is running under unprivileged user, then >> is invoked earlier than privileges are acquired by sudo.
You can use the following approach:
echo >000-default.conf.test
sudo cp 000-default.conf.test /etc/apache2/sites-enabled/000-default.conf.test
echo 'this is a test' | sudo tee -a /etc/apache2/sites-enabled/000-default.conf.test >/dev/null
sudo cat /etc/apache2/sites-enabled/000-default.conf.test
By the way, instead of
echo >000-default.conf.test
you can use
touch 000-default.conf.test
or even
>000-default.conf.test
Related
I'm executing a command with sudo from bash script, and I'm wondering how to prevent sudo from displaying anything on the screen
echo "mypassword" | sudo -S cp -u /scripts/.bashrc ~/ > /dev/null 2>&1
The result will be an output displaying: [sudo] password for username:
I want to hide that output..
now, before the first comment;
This isn't the safest way, since you're entering your password into the script, but this is strictly internal servers.
Run sudo --help, we can get answer from the parameter list:
-p, --prompt=prompt use the specified password prompt
Then,
echo "mypassword" | sudo -S --prompt="" cp -u /scripts/.bashrc ~/ > /dev/null 2>&1
may do the trick.
I need to edit an privileged file using bash on Ubuntu 14.04
This simple command is not working:
sudo echo $someText >> $privilegedFile
I get this error:
Permission denied
I have no idea what is wrong with it.
Thanks.
The shell processes the redirection before it runs sudo, so $privilegedFile is still opened using the current user's permissions.
One workaround is to open the file with a program run by sudo rather than using redirections.
echo "$someText" | sudo tee -a "$privilegedFile"
Another is to start an entirely new shell with sudo and execute the full command in that shell.
sudo sh -c "echo '$someText' >> '$privilegedFile'"
You should try this:
sudo sh -c "echo $text >> $file"
do
sudo chmod u+xrw FILE
and
sudo nano FILE
Don't use echo for editing, try nano, gedit or vi.
I am trying to update the crontab file of 1000+ systems using a for loop from jump host.
The below doesn't work.
echo -e 'pass365\!\n' | sudo -S echo 'hello' >> /var/spool/cron/root
-bash: /var/spool/cron/root: Permission denied
I do have (ALL) ALL in the sudoers file.
This is another solution;
echo 'pass365\!' | sudo -S bash -c 'echo "hello">> /var/spool/cron/root'
The below worked for me.
echo 'pass365\!' | sudo -S echo 'hello' | sudo -S tee -a /var/spool/cron/root > /dev/null
Problem 1: You are trying to send the password via echo to sudo.
Problem 2: You can't use shell redirection in a sudo command like that.
Between the two of these, consider setting up ssh public key authorization and doing
ssh root#host "echo 'hello' \>\> /var/spool/cron/root"
You may eventually get sudo working but it will be so much more pain than this.
This question already has answers here:
Bash Deployment Script Permission Problem
(2 answers)
Closed 8 years ago.
I came across this weird problem just now and I can't seem to get to the bottom of it. I'm trying to add a config file to /etc/sudoers.d/ but get permission denied. In the example below, the file "tweedle" doesn't exist and:
drwxr-xr-x 2 root root 4.0K Jan 2 18:27 sudoers.d/
So here's the command:
$ sudo echo "tweedle ALL=(ALL) ALL" > /etc/sudoers.d/tweedle
-bash: /etc/sudoers.d/tweedle: Permission denied
It doesn't even work when I break it into two commands:
$ sudo touch /etc/sudoers.d/tweedle
$ sudo echo "poodle" > /etc/sudoers.d/tweedle
When I tested it locally, same problem:
$ cd ~
$ mkdir -m 755 tweedle
$ sudo chown root:root tweedle
$ sudo echo "battle" > ~/tweedle/beetle
-bash: /home/spanky/tweedle/beetle: Permission denied
$ sudo touch tweedle/beetle
$ sudo echo "battle" > tweedle/beetle
-bash: tweedle/beetle: Permission denied
Without sudo, all is well:
$ cd ~
$ mkdir poodle
$ echo "noodle" > poodle/bottle
$ cat poodle/bottle
noodle
Thoughts?
The echo command is being run as root, but the redirection is done by your shell, so it's executed as the current user, not as root.
The simplest solution is to invoke a root shell to run both the command and the redirection.
Rather than:
sudo echo line > file
try this:
sudo sh -c 'echo line > file'
or
sudo bash -c 'echo line > file'
The answer is to use "tee" with a pipe, a command I wasn't familiar with, so you can use sudo for the second half:
$ echo "tweedle ALL=(ALL) ALL" | sudo tee /etc/sudoers.d/tweedle
I am trying to write a script that appends a line to the /etc/hosts, which means I need sudoer privileges. However, if I run the script from the desktop it does not prompt for a password. I simply get permission denied.
Example script:
#!/bin/bash
sudo echo '131.253.13.32 www.google.com' >> /etc/hosts
dscacheutil -flushcache
A terminal pops up and says permission denied, but never actually prompts for the sudo password. Is there a way to fix this?
sudo doesn't apply to the redirection operator. You can use either echo | sudo tee -a or sudo bash -c 'echo >>':
echo 131.253.13.32 www.google.com | sudo tee -a /etc/hosts
sudo bash -c 'echo 131.253.13.32 www.google.com >> /etc/hosts'
What you are doing here is effectively:
Switch to root, and run echo
Switch back to yourself and try to append the output of sudo onto
/etc/hosts
That doesn't work because you need to be root when you're appending to /etc/hosts, not when you're running echo.
The simplest way to do this is
sudo bash -c "sudo echo '131.253.13.32 www.google.com' >> /etc/hosts"
which will run bash itself as root. However, that's not particularly safe, since you're now invoking a shell as root, which could potentially do lots of nasty stuff (in particular, it will execute the contents of the file whose name is in the environment variable BASH_ENV, if there is one. So you might prefer to do this a bit more cautiously:
sudo env -i bash -c "sudo echo '131.253.13.32 www.google.com' >> /etc/hosts"