login as another user in a terminal

This is an useful trick specially when we have specific users for certain services - like app servers-  the idea is to login temporally as another user in a terminal, do whatever you have to do and then logout, so, the steps are:

1. open a terminal
2. type: sudo -u myuser02 zsh
3. whoami

That's it, in this case, I use zsh as another terminal, you may use what you like.

Really useful, at least for me

Best

deploying Apache2+WebDAV on Ubuntu

WebDAV is a web authoring built into HTTP that allows to share files and work collaborative .

So, To enable it there are several steps, here they are:

1. enable the appropriated modules:
sudo a2enmod dav
sudo a2nemod dav_fs

2. restart apache:
  sudo servide apache2 restart

3. Then we need to create a directory, it would be great whether this one is outside the DocumentRoot directory, i will create it on /home:
  mkdir /home/me/webdav

4. To gain access from web we need to change the owner to www-data
   chown www-data /home/me/webdav

5. Next, we need to password protect the target directory:
  sudo htpasswd -c /etc/apache2/webdav.password me
  sudo chown root:www-data /etc/apache2/webdav.password
  sudo chmod 640 /etc/apache2/webdav.password

6. Cool, now we need to configure apache to use WebDAV, I will modify the default site configuration file:

Alias /webdav /home/me/webdav


   Order allow,deny
  Allow from all



    Options Indexes
    DAV On
    AuthType Basic
    AuthName "webdav"
    AuthUserFile /etc/apache2/webdav.password
    Require valid-user


7. At this time, we may try our advance, so from a web browser type:
    http://localhost/webdav

  You will be asked for a user and a password

 You might try it using a WebDAV client called cadaver, like this:
  cadaver http://localhost/webdav

8. for security reasons, we may disable the Directory Listing (removing the line Options Indexes) and instead, we may create an html file ( it is mandatory to named index.html), like this:


Main Page

this is the first page displayed once the directory listing is off



save it on /home/me/webdav, restart apache and try to access it

Next, I will write about how to use it in a production environment.

Best

executing commands using sudo without ask for password

Sometimes is annoying write the root password for execute certain commands, specially if you are working on console mode, that's why is really great to custom sudo ( using visudo) in order to avoid the password prompt:

1. open your terminal
2. type sudo visudo
3. then add these lines:

User_Alias MANAGERS = user1, user2

Cmnd_Alias SHUTDOWN = /sbin/reboot, /sbin/halt

4. Then add this line at the end of the file:
MANAGERS ALL = (ALL) NOPASSWD: SHUTDOWN

that's it, save it and try it

At least for me it works putting the NOPASSWD line at the end, I'm not sure if the way SUDO reads this file is from bottom to top, anyway, try it

Best