Table of Contents
Let's get into our Linux VM:
$ cd ~/dso_repos/bootcamp/
$ # vagrant provision
$ # vagrant up
$ vagrant ssh
Download a word list, move it into, its own directory, decompress the word list and count the words.
$ wget http://download.openwall.net/pub/wordlists/all.gz
$ mkdir words
$ mv all.gz words/
$ cd words
$ gunzip all.gz
$ ls -l
$ wc -l all
Count the number of words that start with the first letter of your last name. E.g., if my last name starts with a 'g' I would do the following:
$ grep -e '^g.*' all |wc -l
Create a new text file using vim, nano, or cat. Then, count the words,
$ cat > file.txt
this is my file, there are many like it but this one is mine...
^D
Listing the root filesystem:
$ ls -l /
$ ls /bin
Permissions, here we see that the ls command has read-write-execute permissions for root, and read-execute for everyone else.
$ ls -l /bin/ls
-rwxr-xr-x. 1 root root 117616 Feb 16 10:49 /bin/ls
Relative paths vs full paths.
$ ls -l home
$ ls -l /home
$ ls -la
Most important directories: /etc (configuration), /home (user directories), /var (logs & other), /bin (commands).
$ ls -ld /etc /home /var /bin
Who am I?
$ whoami
$ ls -la
Create a user in /etc as a non-privileged user. Did it work?
$ touch /etc/myfile.txt
Create the file using sudo. Why did it work?
$ sudo touch /etc/myfile.txt
So, what happens when we use sudo?
$ sudo whoami
Let's take a look at /etc/passwd, list all the system usernames.
$ cat /etc/passwd
$ cat /etc/passwd| cut -f1 -d:
List the root users:
grep 'x:0:' /etc/passwd
Did anyone try using nano? Is it installed? Let's install it:
yum install nano
What went wrong? how do we fix it?
Let's install net-tools:
sudo yum -y install net-tools
Now we can list our IP address, list our network routes, and list open ports.
$ ifconfig
$ route
$ netstat -na
How would you list the TCP listening ports? Do it two ways, one just using netstat and the other using grep.