This was driving me batty. I had an issue with one of my linux webservers and it needed to be restored from a backup. Upon restoring the linux server I found my account that I had setup for sudo access no longer would accept the ’sudo su’ command or any sudo command for that matter. I was getting and error that read “Sorry, sudo must be setuid root“.

As I had removed the root account from accessing ssh I had to log into the physical server (lucky it’s just next to me!)

It turns out for some reason after the restore sudo had the wrong permissions.

To fix it was quite simple but took me ages to track down! (Helps if you know exactly what to search for)

I logged in as root and entered the following

chmod 4111 /usr/bin/sudo

All was fine in the land of oz after that!

First I must say that I do not like the Vi editor – I’m a Nano man myself. I might not be hardcore Linux enough (yet) to really appreciate it. One of the things that drives me nuts about it is that its not intuitive or like any other editor- but i guess that’s what makes it so powerful!.

I came across this fanatic article by jbj over at Cats Who Code that details 100 Vi commands to help you get the most out of the editor and with there permission I’ve re produced it here.

Enjoy

Search

• /word Search “word” from top to bottom
• ?word Search “word” from bottom to top
• /jo[ha]n Search “john” or “joan”
• /\<theSearch “the”, “theatre” or “then”
• /the\> Search “the” or “breathe”
• /\< the\> Search “the”
• /\< ….\> Search all words of 4 letters
• /\/ Search “fred” but not “alfred” or “frederick”
• /fred\|joe Search “fred” or “joe”
• /\<\d\d\d\d\> Search exactly 4 digits
• /^\n\{3} Find 3 empty lines
• :bufdo /searchstr/ Search in all open files

Replace

• :%s/old/new/g Replace all occurences of “old” by “new” in file
• :%s/old/new/gw Replace all occurences with confirmation
• :2,35s/old/new/g Replace all occurences between lines 2 and 35
• :5,$s/old/new/g Replace all occurences from line 5 to EOF
• :%s/^/hello/g Replace the begining of each line by “hello”
• :%s/$/Harry/g Replace the end of each line by “Harry”
• :%s/onward/forward/gi Replace “onward” by “forward” , case unsensitive
• :%s/ *$//g Delete all white spaces
• :g/string/d Delete all lines containing “string”
• :v/string/d Delete all lines containing which didn’t contain “string”
• :s/Bill/Steve/ Replace the first occurence of “Bill” by “Steve” in current line
• :s/Bill/Steve/g Replace “Bill” by “Steve” in current line
• :%s/Bill/Steve/g Replace “Bill” by “Steve” in all the file
• :%s/\r//g Delete DOS carriage returns (^M)
• :%s/\r/\r/g Transform DOS carriage returns in returns
• :%s#<[^>]\+>##g Delete HTML tags but keeps text
• :%s/^\(.*\)\n\1$/\1/ Delete lines which appears twice
• Ctrl+a Increment number under the cursor
• Ctrl+x Decrement number under cursor
• ggVGg? Change text to Rot13

Case

• Vu Lowercase line
• VU Uppercase line
• g~~ Invert case
• vEU Switch word to uppercase
• vE~ Modify word case
• ggguG Set all text to lowercase
• :set ignorecase Ignore case in searches
• :set smartcase Ignore case in searches excepted if an uppercase letter is used
• :%s/\<./\u&/g Sets first letter of each word to uppercase
• :%s/\<./\l&/g Sets first letter of each word to lowercase
• :%s/.*/\u& Sets first letter of each line to uppercase
• :%s/.*/\l& Sets first letter of each line to lowercase

Read/Write files

• :1,10 w outfile Saves lines 1 to 10 in outfile
• :1,10 w >> outfile Appends lines 1 to 10 to outfile
• :r infile Insert the content of infile
• :23r infile Insert the content of infile under line 23

File explorer

• :e . Open integrated file explorer
• :Sex Split window and open integrated file explorer
• :browse e Graphical file explorer
• :ls List buffers
• :cd .. Move to parent directory
• :args List files
• :args *.php Open file list
• :grep expression *.php Returns a list of .php files contening expression
• gf Open file name under cursor

Interact with Unix

• :!pwd Execute the “pwd” unix command, then returns to Vi
• !!pwd Execute the “pwd” unix command and insert output in file
• :sh Temporary returns to Unix
• $exit Retourns to Vi

Alignment

• :%!fmt Align all lines
• !}fmt Align all lines at the current position
• 5!!fmt Align the next 5 lines

Tabs

• :tabnew Creates a new tab
• gt Show next tab
• :tabfirst Show first tab
• :tablast Show last tab
• :tabm n(position) Rearrange tabs
• :tabdo %s/foo/bar/g Execute a command in all tabs
• :tab ball Puts all open files in tabs

Window spliting

• :e filename Edit filename in current window
• :split filename Split the window and open filename
• ctrl-w up arrow Puts cursor in top window
• ctrl-w ctrl-w Puts cursor in next window
• ctrl-w_ Maximise current window
• ctrl-w= Gives the same size to all windows
• 10 ctrl-w+ Add 10 lines to current window
• :vsplit file Split window vertically
• :sview file Same as :split in readonly mode
• :hide Close current window
• :only Close all windows, excepted current
• :b 2 Open #2 in this window

Auto-completion

• Ctrl+n Ctrl+p (in insert mode) Complete word
• Ctrl+x Ctrl+l Complete line
• :set dictionary=dict Define dict as a dictionnary
• Ctrl+x Ctrl+k Complete with dictionnary

Marks

• mk Marks current position as k
• ‘k Moves cursor to mark k
• d’k Delete all until mark k

Abbreviations

• :ab mail mail@provider.org Define mail as abbreviation of mail@provider.org

Text indent

• :set autoindent Turn on auto-indent
• :set smartindent Turn on intelligent auto-indent
• :set shiftwidth=4 Defines 4 spaces as indent size
• ctrl-t, ctrl-d Indent/un-indent in insert mode
• >> Indent
• << Un-indent

Syntax highlighting

• :syntax on Turn on syntax highlighting
• :syntax off Turn off syntax highlighting
• :set syntax=perl Force syntax highlighting

I’ve been asked here on my blog about creating user accounts and giving them access to folders such as /var/www or creating ftp users that link to a single folder. That was quite a while ago. Since then i have picked up quite a bit about user management and thought that i would let you in on my findings.

In Part 1 I’m going to show you how to add and manage user accounts. Learning these features has been a critical part of efficiently managing the 10+ Linux servers.

In order to create new logins, modify or delete users, you must already be logged in as sudo user. The sudo user login is the highest level (assuming you have the root account disabled) and only certain individuals should have access to a sudo account.

useradd – Adding a new user

Each user must belong to a primary group and for security or access purposes can belong to several secondary groups.

Options:

• -d home directory
• -s starting program (shell)
• -p password
• -g (primary group assigned to the users eg -gwww-data (note no space between the -g and www-data)
• -G (Other groups the user belongs to eg -Gusers (note no space between the -g and users)
• -m (Create the user’s home directory

usermod – Modifying existing user

Options:

• -d home directory
• -s starting program (shell)
• -p password
• -g (primary group assigned to the users)
• -G (Other groups the user belongs to)

userdel – Deleting a user

Options:

• -r (remove home directory)

Example: To remove the user ‘rebecca’ and his home directory

userdel -r rebecca

passwd – User’s Password

Options:

• user’s name (Only required if you are root and want to change another user’s password)

Example: To change the password for the account you are currently logged in as…

1. passwd
2. Enter existing password
3. Enter new password
4. Enter new password again (to validate)

Example: To change the password for the user ‘mark’ (only you are logged in as a sudo user)…

1. passwd mark
2. Enter existing password (can be either marks’s password or sudoer’s password)
3. Enter new password
4. Enter new password again (to validate)

Where user and group information stored

User names and primary groups are stored in /etc/passwd. This file can be directly edited using the ‘vi’ editor, although this is not recommended. Format of the file is…

• User name (normally all lower case)
• Password (encrypted – only contains the letter ‘x’)
• User ID (a unique number of each user)
• Primary Group ID
• Comment (Normally the person’s full name)
• Home directory (normally /home/
• Default shell (normally /bin/bash)

Each field is separated by a colon.

Passwords for each user are stored in /etc/shadow. This file should only be changed using the passwd command.

Group information is stored in /etc/group. This file can be directly edited using the ‘vi’ editor. Format of the file is…

• Group name
• Group password (hardly ever used)
• Group ID
• User names (separated by commas)

Each field is separated by a colon.

Default files

When a new user is created, the default files and directories that are created are stored in /etc/skel.

This directory can be modified to fit your needs. Modifications only effect new users and does not change anything for existing users.

su – Switch User

To switch to another user, use the su command. This is most commonly used to switch to the root account.

Example: To switch to root account…

1. su
2. Enter root’s passwd

Example: To switch to the user ‘rebecca’…

su rebecca

Enter Rebecca’s or the sudoer’s passwd

To return to original user, enter exit

Well there you go. In Part 2 I’m going to go over how to add users for the web folders including FTP users that are limited to their home folder.

I’m not interested in using Linux for my desktop, Gnome and KDE really don’t do it for me and Windows XP is doing me fine – though I am looking forward to moving my studio onto a Mac Pro. Another big reason Linux as a desktop isn’t for me is that Adobe’s Creative Suite 3 does not, and won’t by the looks of things, support any flavor of Linux.

I’m after a new Server environment. I’m in the process of switching from Classic ASP (ASP3) over to PHP5. I’ve been using MySQL religiously for my dev work. But what I really want access to is the speed and reliability of Apache and PHP running on Linux. Also the chmod in ftp will save SO MUCH TIME when setting up blogs or any other site that requires permission changes.

So it’s time to learn – and by learning I mean command lines. Back to the good ‘ol DOS days.

I found Ubuntu 7.10 Server to be the solution for me. Why? Because a) It’s built on Debian and 2) they are the best at marking their flavor of Linux and bringing it to the attention of us Windows users.

Also a great feature that I found is that in around 15 minutes you can have a LAMP (Linux, Apache, MySQL and PHP) server up and ready to go! You just select it during installation!

The LAMP option means you don’t have to install and integrate each of the four separate LAMP components, a process which can take hours and requires someone who is skilled in the installation and configuration of the individual applications. Instead, you get increased security, reduced time-to-install, and reduced risk of misconfiguration, all of which results in a lower cost of ownership. New pre-configured installation options have been added to the Ubuntu Server. Mail Server, File Server, Print Server, and Database Server options join existing LAMP and DNS options for pre-configured installations, easing the deployment of common server configurations.

Here’s what will be installed

• Ubuntu Gutsy Gibbon 7.10
• Apache 2.2.4
• Mysql 5.0.45
• PHP 5.2.3

Installing Ubutnu Server I found to be really simple and once I did it a couple of times (due to errors on my behalf) I quickly found it even easier to install then Windows 2003 Server

You’ll need to first download Ubuntu Server from http://www.ubuntu.com/getubuntu/download. Burn the ISO or mount it in VMWare if you are installing it on a virtual machine. Insert the CD a make sure you BIOS is set to boot from the CD/DVD drive

1. Select “Install to the Hard Disk”
   
2. Select your language
   
   
   
3. Select your location
   
4. Ubuntu Server can try and detect your keyboard layout. For the most people will be using US English. Select No and chose your layout yourself.
   
   
   Go through the options for your keyboard. The installation will then detect your hardware.
5. Enter ubuntuLamp or what ever you want to call your Server
   
6. The installer will detect your Hard Drive. Select “Guided – use entire disk”
   
7. When you receive the screen title “[!!] Partion Disks” select <Yes> and hit enter
   
8. Select <Yes> when presented about the system clock
   
9. Enter in administration for your name
   
   
10. Enter in administrator for your username
    
    
11. Enter in a secure password (here is a great article on coming up with a secure password that you can remember)
    
12. When you are presented with the screen [!] Software selection press the down arrow till the “* is in the “LAMP server” box and press space bar. As were also going to be using SSH I also select “OpenSSH server”
    
    
13. You’ll be presented with the option to change the MySQL root password. This is highly recommended as the standard password is blank
    
    
14. You’re done! Remove the CD from the CD drive and reboot
    
    
15. You server is now installed.
    
    
    

Next I configure a Static IP.

Log into your server using the details you entered during install. I’m using 192.168.0.150 as my example IP)

Type

sudo su

and enter your password again

Then Type

nano /etc/network/interfaces

If you have typed it out correctly you’ll Also you will see the following:

# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
 
# The loopback network interface
auto lo
iface lo inet loopback
 
# The primary network interface
auto eth0
iface eth0 inet dhcp

Replace the last 3 lines with the following:

# The primary network interface
auto eth0
iface eth0 inet static
address 172.19.0.10
netmask 255.255.255.0
network 172.19.0.0

Try Ctrl+O to write the file and then press enter

Type Ctrl+X to exit

To set your Nameservers, type

nano /etc/resolv.conf

Enter in your nameservers as required “nameserver xxx.xxx.xxx.xxx”

Type Ctrl+O to write the file and then press enter

Type Ctrl+X to exit

Now you need to restart your network service. Type the following

/etc/init.d/networking restart

You’ve now configured your network interface.

I also wanted to also install Webmin to manage my server remotely as well as SSH but I found that the install instructions on the above site just didn’t work for me. So here is how I installed Webmin on my Ubuntu Server.

You will need to enable the universe and universe and multiverse repositories in the /etc/apt/sources.list (https://wiki.ubuntu.com/AddingRepositoriesCliHowto)

This is also where I started to use Putty and SSH (http://the.earth.li/~sgtatham/putty/latest/x86/putty.exe)

sudo su
mkdir /opt/Webmin
cd /opt/Webmin
wget http://easynews.dl.sourceforge.net/sourceforge/webadmin/Webmin-1.390.tar.gz
gzip -cd Webmin-1.390.tar.gz | tar xvf -
sudo apt-get install libauthen-pam-perl libnet-ssleay-perl libpam-runtime openssl perl perl-modules

Note I had heaps of problems with this command and it was to do with my sources.list file. No matter what I uncommented it just didn’t seam to work. I had to generate a new sources.list file from this site (http://www.ubuntu-nl.org/source-o-matic/) and past that into /etc/apt/sources.list then run sudo apt-get update before the above command would run

 cd Webmin*
./setup.sh

Basically just hit enter and choose SSL and the auto start the service at boot. Use these settings (or change as requried)

Web server port (default 10000): (Feel Free to change this) Login name (default admin): Login password: AReallyGoodONE Password again: AReallyGoodONE Use SSL (y/n): y Start Webmin at boot time (y/n): y

I found that the default instating module for PHP looks for the php.ini file in the Apache directory when it needs to look in the apache2 directory. After instating login into Webmin by visiting https://your-ip:10000 and click on “Other” in the right bar. Then click on “PHP Configureation” You should see that following:

/etc/php5/apache/php.ini=Configuration for mod_php
/etc/php5/cgi/php.ini=Configuration for scripts run via CGI
/etc/php5/cli/php.ini=Configuration for command-line scripts

Change the line /etc/php5/apache/php.ini=Configuration for mod_php to read /etc/php5/apache2/php.ini=Configuration for mod_php and click save

This should have configured the PHP moduble for Webmin for you.

FTP

Now were going to install ProFTPD FTP server.

Login into your Ubuntu Server via SSH, or how ever you wish to access the console, and type:

sudo apt-get install proftpd

When asked if you want to install the server as a inid or standalone, select standalone and continue.

Done! Now if you check back in Webmin under Servers you’ll see ProFTPD Server, if you click on that you should see the ProFTPd options up and running.

Adding a FTP user is done through the “System => Users and Groups” area in Webmin. You just click on “Create a new user” enter in the details and select the home directory to /var/www (make sure you click the check box next to the home directory text box as it stays checked at “Automatic” even once you enter something into the text box.)

Fire up your ftp client and login!

You should now have a working LAMP+F (Linux, Apache, MySQL, PHP and FTP) Ubuntu Server. Next I’ll be looking into securing the server. I’ve read that ProFTPD isn’t the most secure FTP Server to use with Linux, apparently VSFTPD is the way to go there, but for the purpose of simplicity for the first time, and the fact that this is not a live server, rather just a testing box, it’s not such a big deal.

Please post your comments on this, if you find it useful please let me know – anything that needs further clarification tell me – I’m new to Linux as you might be so this is a big change.

You don’t need a hardware switch to share one keyboard and mouse amongst several different computers. All you need is the free, cross-platform application, Synergy.Synergy connects one keyboard and mouse to any computer on your network, making a dual- or triple-computer setup work more like a dual- or triple-monitor setup. Synergy even allows you to share clipboard data across your computers and operating systems.

Today I’ll detail how to set up Synergy on your home network to control all of your desktops with one mouse and keyboard.

How it works

Synergy uses one computer as a server – that’s the computer that will be sharing its keyboard and mouse. The rest of your computers – the ones you want to control – will need to be set up as Synergy clients.

The great part about Synergy is that you can customize the program to work with the layout of your computers. For example, if you’ve got your MacBook running to the left of your Windows PC, you can set up Synergy so that moving your mouse to the left of your Windows monitor will seamlessly jump your mouse across virtual space where it lands safely on your Mac. Whichever desktop currently holds your mouse is also the desktop to which your keyboard’s keystrokes will be sent. Make sense? Add to that Synergy’s clipboard sharing and you’ve got one helluva convergence app.

Click here for detailed install instructions (ignore the “Hack Attack” in the heading, this is not a hack by any means, and probably doesn’t do the original post any justice.)

Something that drives me nuts is my wifes passwords. Constantly really simple easy to crack passwords. It makes securing our wireless network also imposable.

Fortunately corvusconsulting.ca has put together a 4 part guide to choosing and remembering a secure password.

Here’s a snippet:

When choosing a word, aim for something between 4 and 6 characters. This gives you a wide range to play within, and allows you to pick a word that is personally memorable. There is a great advantage to choosing a word from a foreign language, in that it’s unlikely to be included in dictionary attacks, a basic tool in any password cracker’s toolkit. Don’t know a word from another language? They’re easy to find, and to base it on a word in your native language you can just translate by using the venerable Babelfish. By the way, I owe credit to Tod Maffin, who clued me into using a foreign word as part of a password.

Read part 4 of the article here (the pate about actually creating the password)

Update: I forgot to mention that you need to have “Custom Error Documents” turned on. To do this in plesk, Navigate to your domains hosting page, click on “Setup” under Hosting. Scroll down to Services and select “Custom Error Documents” and then click ok.

Edited – 06/08/07 2:27pm

I’m going to step you through how I went about installing Nathan Moinvaziri’s plugin and set up Wordpress 2.2 to use Permalinks in an IIS6 enviroment with Plesk 8 installed.NOTE: This worked for me, and my hosting environment. I have no idea if it will work for everyone. I will not be held responsible for any damage you do to your blog. You have been warned.

Configure Plesk

Log into Plesk

Navigate to your domains control page.

Click on the icon “Web Directories”

Click on the tab “Error Documents”

Locate the entrie that reads “404 Not Found” and click on it. You may need to navigate to the next page to see it.

Drop down the “Type” box and select “URL”

In the “Location Box” type “/” (Without the quotation marks)

Click “Ok”

Log out of Plesk

Visit “http://www.nathanm.com/myprojects/#plugin” (opens in a new window)

Find the Plugin “Wordpress - Remove Index.php from Permalinks in IIS Plugin”

Upload the php file “removeindex.php” to your wordpress plugins directory
Log into Wordpress admin.
Click on “Plugins”

Locate the “Remove index.php” plugin and click on “Activate”

Click on “Options” then “Permalinks”

Set your Permalinks Structure. First click one of the common options. Then click on the “Custom, specify below” box and remove “index.php”. I use /%year%/%category%/%postname%/ for my structure.

Click “Update Permalinks Structure”

And your done :D

Check to make sure that everything is working. If you have sitemaps, it’s best to re generate them and submit them to google. The old ?p=34 strings will still work though. Test everything.

Writing 70-642 is easier for 642-642 series students who have done 642-845 as compared to 350-018 students who have not even done 70-647.

I’ve been able to find a solution that actually solves the problem and makes permalinks on IIS work right without the “index.php” in the URL!

If you can follow this then it’ll be sweet and simple!

Nathan Moinvaziri

http://www.nathanm.com/

Install Instructions

To remove the Index.php from Wordpress you must do the following.

Redirect your custom 404 error page to / or to the root relative path of your blog.
Remove the /index.php part from your permalinks option in Wordpress.
Install and activate the plugin.

The solution can be found at http://www.nathanm.com/myprojects/#plugin.

About halfway down the page, you’ll see “Wordpress – Remove Index.php from Permalinks in IIS Plugin” with a link pointing to the plugin ZIP file located at http://www.nathanm.com/projects/removeindex.zip.

I will write a post with a complete step-by-step walkthrough of how to set this up using WSFTP, Plesk 8 and Wordpress 2.2.1 in the next day or two.