How to execute and log as specific user? - bash

I need to run a command/shell-script as on other user. The stdout shall be written to a logfile.
I tried it like this:
export LOGDIR=foo/bar
sudo -u www command /home/www > /home/www/$LOGDIR/command.log
But I get always this error:
-bash: /home/www/foo/bar/command.log: Permission denied
You can try this easily with this little stupid example:
sudo -u edeviser ls /home/edeviser > /home/edeviser/$LOGDIR/ls.log
I see the problem is, that the redirection with > is not done as the user specified by the ´-u´ option.
How to execute the command and log as the same specific user?

You can try something like
sudo -u www bash -c "command /home/www > /home/www/$LOGDIR/command.log"

export logdir="foo/bar"
sudo -u www command /home/www |sudo -u www dd of="/home/www/$logdir/command.log"

Related

Executing sudo command in bash script without displaying it

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.

Is there any way to redirect output from smbclient?

I know that smbclient does not allow output redirection but is there any workaround for this to get the output to either text file or std?
have you tried this:
$ smbclient -U USER%PASSWORD //IPTOSHARE/DIRECTORY/ -c 'cd ANOTHERDIR; dir' > sampletext.txt

Edit an privileged file via bash

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.

Update root crontab remotely for many systems by script

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.

Sudo not prompting for password Mac bash script

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"

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