DevOps BootCamp¶

and

$ONE_VARIABLE_NOTATION
<another notation for variables>

copy_me_exactly
this_is(code)  # everything after the octothorp is a comment!

other_code(line)  // This can also be a comment. It depends on the
                  // language!

#! /usr/bin/env python
# This is a code block.
# Most of the time you can copy this code and run it exactly as is.
# It should be clear Where it 'goes' and how to run it based on
# context.
print('Hello world!')

# Copy the text after `$` into your terminal & press enter.
$ echo Hello World

#!/bin/python
dogs = ['$BREED_ONE', '$BREED_TWO', '$BREED_THREE']
for breed in dogs:
    print(breed)

$BREED_ONE
$BREED_TWO
$BREED_THREE

$BREED_N
#!/bin/python
dogs = ['corgie', 'pug', 'french bulldog']
for breed in dogs:
    print(breed)

corgie
pug
french bulldog

scp
$ git clone https://github.com/DevOpsBootcamp/Bootcamp-Exercises.git
$ cd Bootcamp-Exercises
$ docker-compose up -d
$ docker-compose run -p 8080:8080 dobc bash

exit
$ docker-compose kill
$ docker-compose rm --all

ubuntu
debian
centos
fedora
$ docker run -it --rm <docker image name> bash

$ git clone https://github.com/DevOpsBootcamp/vagrant.git
$ cd vagrant
$ vagrant up
$ vagrant ssh

$ passwd
Changing password for user <user>.
Changing password for <user>.
(current) UNIX password: # Enter old password, hidden
New password:   # Enter new password, also hidden
Retype new password:
passwd: all authentication tokens updated successfully.

$ <program> --help
$ <program> -h

help
$ man <program>

/
n
p
$ man man

MAN(1)             Manual pager utils                       MAN(1)

NAME
       man - an interface to the on-line reference manuals

SYNOPSIS
       man  [-C  file]  [-d]  [-D]  [--warnings[=warnings]] [-R
       encoding] [-L locale] [-m system[,...]] [-M path] [-S list]
       [-e  extension]  [-i|-I] [...]

DESCRIPTION
       man is the system's manual pager.  Each page argument given
       to man  is normally  the name of a program, utility or
       function.  The manual page [...]

man
man
#  <program or library>
#
$ man 2 open # Displays the kernel documentation for open (section 2)
$ man open   # Displays the documentation for openvt (section 1)

open
open()
man
man(7)
groff(7)
info
man
info
man
# This step is optional, but persistent IRC is cool
$ ssh <username>@<a remote linux server>

# start screen with the name 'irc'
$ screen -S irc

# start your client in the 0th window of the screen session
$ irssi
# or
$ weechat-curses

# exit irc screen with CTRL+a, CTRL+d
# exit ssh session with CTRL+d or 'exit'
# to get back to irc:
$ ssh <username>@<preferred shell host>
$ screen -dr IRC

/connect irc.freenode.net
/nick <myawesomenickname>
/msg nickserv register <password> <email>
/nick <myawesomenickname>
/msg nickserv identify <password>
/join #devopsbootcamp

/server add freenode irc.freenode.net
/connect freenode
/nick <myawesomenickname>
/msg nickserv register <password> <email>
/nick <myawesomenickname>
/msg nickserv identify <password>
/join #devopsbootcamp

/list
/topic
/names
/join <channel>
/whois <nick>
/msg
/help <command>
@
+
chanserv
nickserv
/msg nickserv help
/msg chanserv help
info
sh
bash
csh
zsh
fish
# Prints the current working directory (where you are)
$ pwd
# Prints the contents of the current working directory
$ ls
# Navigates to a new directory.
$ cd <path/to/other/directory>
# Prints a string to the screen.
$ echo "some thing $AND_VARS"
# Prints the contents of a file(s) to the screen.
$ cat foo.txt bax.txt
# Searches `file.txt` for the string `foo`
$ grep foo file.txt
# Prints a file to the screen so you can arrow up/down.
$ less file.txt
# Prints environment variables to the screen.
$ env
# Prints out current user
$ whoami
# When in doubt, always type help.
$ help

about_me.sh
#!/bin/sh
if [ $(whoami) == "root" ]; then
  echo "You're root!"
else
  echo "Your username is $(whoami)"
  echo "Your home-directory is $HOME"
  echo "Your current directory is $PWD"
  echo "Your computer's host-name is $HOSTNAME"
fi

# Tell Linux that this can be run as a program
$ chmod +x about_me.sh
# Invoke the script.
$ ./about_me.sh
Your username is dobc
Your home-directory is /home/dobc
Your current directory is /home/dobc
Your computer's host-name is dobc

$ grep 'searchstring' files/* | less

$ true || echo 'never gets here'
$ false && echo 'never gets here'

$ echo 'this now an error message' 1>&2 | grep -v error
this is now an error message

!$ # last argument to last command
$ cat /dir
cat: /dir/: Is a directory
$ cd !$
cd /dir
$ pwd
/dir

$ for x in 1 2 3; do echo $x; done # Use seq for longer sequences
1
2
3

$ var='this is a var'; echo ${var//this is } # Deletes 'this is '
a var

$ ls -l `which bash`
-rwxr-xr-x 1 root root 1029624 Nov 12 15:08 /bin/bash

$ set -a blocks
$ blocks="10.0.0.0/24"
$ set -a ips
$ ips=`fping -g 10.0.0.0/24 2>&1 | grep unreachable | tr \\  \\n`
$ for ip in $ips; do
$   nmap -p 22 $ip && ips=`echo ${ips//$ip} \
    | tr -s \\n`
$ done
$ echo $ips

name () {
# code goes here
}

$*
$?
"$@"
$CDPATH
$HOME
$IFS
$OLDPWD
$PATH
$PWD
$SHELL
$UID
$USER
.
..
~
/
one_dir/another_dir/last_dir
$ tree -F
.
├── bar/
│   ├── one/
│   └── two
├── baz/
└── foo/
    └── a/
        └── b
5 directories, 2 files

*
cat *.log
.log
$
{ }
ls {foo,bar,baz}ley-thing
ls fooley-thing barley-thing bazley-thing
\
tab
tab
$ ls b    # <tab>
$ ls ba   # <tab>
bar_thing/ baz_thing/
$ ls bar  # <tab>
$ ls bar_thing

^ + <key>
control + key
emacs
vi/vim
nano
nano
$ nano              # Open with empty file
$ nano <file_name>  # Edit a specific file

nano
hello_world.sh
#!/bin/bash
# declare STRING variable
STRING="Hello World"
# print variable on a screen
echo $STRING

chmod
$ chmod +x hello_world.sh
$ ./hello_world.sh
Hello World

$1
$2
foo.sh bar
$1
bar
$@
#!/bin/bash
echo $1   # prints argument #1 given to script
echo $@   # prints all arguments given to script

read
read
-a
#!/bin/bash
echo -e "Tell me a word: \c"
read word
echo "Your word is $word"

$ ./read.sh
Tell me a word: foo
Your word is foo

if
else
then
fi
#!/bin/bash
if [ "$1" == "foo" ] ; then
  echo "You said $1"
else
  echo "You did not say foo"
fi

$ ./sayfoo.sh foo
You said foo
$ ./sayfoo.sh bar
You did not say foo

tar
backup.sh
dobc
/tmp/dobc-backup.tar.gz
args.sh
echo
input.sh
ifelse.sh
"Yay, they match!"
"Boo, they don't match :("
#!/bin/bash
# The flags for tar do the following:
# v - verbose
# c - compress
# z - use gzip
# f - output to file
tar -vczf /tmp/dobc-backup.tar.gz /home/dobc

$ ./backup.sh
tar: Removing leading `/' from member names
/home/dobc/
/home/dobc/backup.sh
/home/dobc/hello_world.sh
/home/dobc/.bash_profile
/home/dobc/.bashrc
/home/dobc/.bash_logout

#!/bin/bash
echo $@
echo $3 $2 $1

$ chmod +x args.sh
$ ./args.sh DOBC is awesome
DOBC is awesome
awesome is DOBC

#!/bin/bash
echo -e "Tell me a noun: \c"
read noun
echo -e "Tell me a verb: \c"
read verb
echo -e "Tell me an adjective: \c"
read adj
echo "I plan to $verb a $adj $noun"

$ ./input.sh
Tell me a noun: apple
Tell me a verb: eat
Tell me an adjective: large
I plan to eat a large apple

#!/bin/bash
if [ "$1" == "$2" ] ; then
  echo "Yay, they match!"
else
  echo "Boo, they don't match :("
fi

$ ./ifelse.sh foo foo
Yay, they match!
$ ./ifelse.sh foo bar
Boo, they don't match :(

$ whoami    # your username
$ who       # who is logged in?
$ w         # who is here and what are they doing?
$ id        # user ID, group ID, and groups you're in

/etc/passwd:
root:x:0:0:root:/root:/bin/bash
username:password:uid:gid:uid info:home directory:shell

/etc/passwd
$ cat /etc/passwd
# username:x:UID:GID:GECOS:homedir:shell

$ useradd <user_name>  # vs adduser, the friendly Ubuntu version
$ userdel <user_name>
$ passwd

groupmod
usermod
groupmod
/etc/passwd
/etc/group
$ groupadd
$ usermod
$ groupmod
$ cat /etc/group
    root:x:0:
    daemon:x:1:
    bin:x:2:
    sys:x:3:
    adm:x:4:
    tty:x:5:
# group name:password or placeholder:GID:member,member,member

/etc/shadow
/etc/passwd
user@localhost ~ $ ls -l /etc/ | grep shadow
-rw-r-----  1 root shadow   1503 Nov 12 17:37 shadow

$ sudo su -
$ cat /etc/shadow
daemon:*:15630:0:99999:7:::
bin:*:15630:0:99999:7:::
sys:*:15630:0:99999:7:::
mail:*:15630:0:99999:7:::

# name:hash:time last changed: min days between changes: max days
#    between changes:days to wait before expiry or disabling:day of
#    account expiry

$ chage # change when a user's password expires

sudo
man 5 sudoers
# User alias specification
User_Alias  DOBC_ADMIN = lance, teacher
User_Alias  DOBC_STUDENT = john, jane

# Runas alias specification
Runas_Alias ADMIN = root, sysadmin
Runas_Alias STUDENT = httpd

# Host alias specification
Host_Alias OSU_NET = 128.193.0.0/16
Host_Alias SERVERS = www, db

# Cmnd alias specification
Cmnd_Alias KILL = /bin/kill
Cmnd_Alias SU = /bin/su

#  User privilege specification
root          ALL = (ALL) ALL
DOBC_ADMIN    ALL = NOPASSWD: ALL
DOBC_STUDENT OSU_NET = (STUDENT) KILL, SU

$ su joe            # become user joe, with THEIR password
$ su                # become root, with root's password
$ sudo su -         # become root, with your password
$ sudo su joe       # become user joe with your password

su
su -
sudo
[dobc@dobc ~]$ yum install httpd      # Runs command as `dobc` user.
Loaded plugins: fastestmirror, ovl
ovl: Error while doing RPMdb copy-up:
[Errno 13] Permission denied: '/var/lib/rpm/__db.002'
You need to be root to perform this command.

[dobc@dobc ~]$ sudo yum install httpd # Runs command as `root` user.
password:
Loaded plugins: fastestmirror, ovl
[... installs correctly ...]

sudo
su
bootcamp
devops
$ sudo su -
$ useradd lance
# better to use visudo instead
$ echo "lance ALL = (ALL) ALL" >> /etc/sudoers
$ passwd lance
Changing password for user lance.
New password:
Retype new password:
passwd: all authentication tokens updated successfully.
$ su - lance
$ mkdir bootcamp
$ sudo groupadd devops

We trust you have received the usual lecture from the local System
Administrator. It usually boils down to these three things:

    #1) Respect the privacy of others.
    #2) Think before you type.
    #3) With great power comes great responsibility.

[sudo] password for lance:

$ ls -il
total 8
2884381 drwxrwxr-x 5 test test 4096 Nov  6 11:46 Documents
2629156 -rw-rw-r-- 1 test test    0 Nov 13 14:09 file.txt
2884382 drwxrwxr-x 2 test test 4096 Nov  6 13:22 Pictures

int read_device_data(int device_file_pointer) {
    // Open a connection to the device
    int * stream = open(device_file_pointer);
    // Write the stream of data to the screen
    write(STDOUT, stream);
    // Do some other stuff with that data
    // Close the data stream
    close(stream);

    return EXIT_SUCCESS;
}

$ ls -l
crw-rw-rw- 1 root  tty   5, 0 Jan  6 13:45 /dev/tty
brw-rw---- 1 root  disk  8, 0 Dec 21 14:12 /dev/sda
srw-rw-rw- 1 root  root  0    Dec 21 14:13 /var/run/acpid.socket
prw------- 1 lance lance 0    Jan  5 17:44 /var/run/screen/S-lance/12138.ramereth
lrwxrwxrwx 1 root  root  4    Nov 25 09:26 /var/run -> /run

$ stat /etc/services
  File: `/etc/services'
  Size: 19303       Blocks: 40         IO Block: 4096   regular file
Device: fc00h/64512d  Inode: 525111      Links: 1
Access: (0644/-rw-r--r--)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2015-01-07 08:22:43.768316048 -0800
Modify: 2012-05-03 09:01:30.934310452 -0700
Change: 2012-05-03 09:01:30.982310456 -0700
 Birth: -

.jpg
.txt
.py
$ ls
some_text_file  squirrel

$ file some_text_file
some_text_file: ASCII text

$ file squirrel
squirrel: JPEG image data, JFIF standard 1.01

.
-a
ls
$ ls
Documents  file.txt  Pictures

$ ls -a
.  ..  Documents  file.txt  .hidden_file  Pictures  .vimrc

ls -l
$ ls -l
drwxrwxr-x   5   test     test     4096   Nov  6 11:46 Documents
-rw-rw-r--   1   test     test        0   Nov 13 14:09 file.txt
drwxrwxr-x   2   test     test     4096   Nov  6 13:22 Pictures
----------   -   ----     ----     ----   ------------ --------------
    |        |    |        |         |         |             |
    |        |    |        |         |         |        File Name
    |        |    |        |         |         +--- Modification Time
    |        |    |        |         +-------------  Size (in bytes)
    |        |    |        +-----------------------       Group
    |        |    +--------------------------------       Owner
    |        +-------------------------------------  References Count
    +----------------------------------------------  File Permissions
                                                         & Type

chown
chmod
chgrp
# Change the owner of myfile to "root".
$ chown root myfile

# Change the owner of myfile to "root" and group to "staff".
$ chown root:staff myfile

# Change the owner of /mydir and subfiles to "root".
$ chown -hR root /mydir

# Make the group devops own the bootcamp dir
$ chgrp -R devops /home/$yourusername/bootcamp

+-----+--------+-------+
| rwx | Binary | Octal |
+-----+--------+-------+
| --- | 000    | 0     |
| --x | 001    | 1     |
| -w- | 010    | 2     |
| -wx | 011    | 3     |
| r-- | 100    | 4     |
| r-x | 101    | 5     |
| rw- | 110    | 6     |
| rwx | 111    | 7     |
+-----+--------+-------+

$ chmod ug+x my_script.sh
# Adds the permission to execute the file to its
# owner user and owner group.

$ chmod o-w myfile.txt
# Removes the permission to write to the file
# from users other than its owners.

$ ls -lh my-script
-r-xr-xr-x 1 username username 1.9K Sep 27 09:44 my-script

$ cat my-script
#!/bin/bash
# The above line tells Linux how to invoke the script on my behalf.
echo 'This is a script being run without using bash!'

$ ./my-script  # my-script is invoked just like a compiled binary!
This is a script being run without using bash!

-
d
b
l
+r
+w
+x
$ ls -alh | grep foobarbaz
drw-rw-rw-  2 voigte   voigte   4.0K Sep 29 10:47 foobarbaz

# Below is the literal output, not pseudo-output
$ ls -alh foobarbaz
ls: cannot access foobarbaz/.: Permission denied
ls: cannot access foobarbaz/..: Permission denied
total 0
d????????? ? ? ? ?            ? .
d????????? ? ? ? ?            ? ..

# create empty file called foo
$ touch foo

/home/dobc/bootcamp
devops
allperms
+rwx
$ touch bootcamp/emptyfile
$ ls -alh bootcamp/emptyfile
-rw-rw-r-- 1 dobc dobc 0 Nov  3 22:38 bootcamp/emptyfile
# You may need to create the devops group.
$ sudo chown dobc:devops bootcamp/emptyfile
# Alternatively, you can also do the following
$ sudo chgrp devops bootcamp/emptyfile
$ touch allperms
$ chmod ugo+rwx allperms
$ ls -l allperms
-rwxrwxrwx 1 dobc dobc 0 Nov  3 22:39 allperms

$ ldd /usr/bin/nano
  linux-vdso.so.1 =>  (0x00007ffc1fdcd000)
  libncursesw.so.5 => /lib64/libncursesw.so.5 (0x00007ff2cfaee000)
  libtinfo.so.5 => /lib64/libtinfo.so.5 (0x00007ff2cf8c4000)
  libc.so.6 => /lib64/libc.so.6 (0x00007ff2cf500000)
  libdl.so.2 => /lib64/libdl.so.2 (0x00007ff2cf2fc000)
  /lib64/ld-linux-x86-64.so.2 (0x000055e46c4b4000)

pip
gem
rubygems
cabal
npm
sl
git
gcc
make
ncurses-devel
git
make
sl
~/local/bin/
$PATH
$HOME/local/bin
whereis sl
sl
sl
$ sudo yum install git gcc make ncurses-devel
$ git clone https://github.com/mtoyoda/sl.git
$ cd sl
$ make
gcc -O -o sl sl.c -lncurses
$ mkdir -p ~/local/bin
$ cp sl ~/local/bin/
$ echo "export PATH=$HOME/local/bin:$PATH" >> ~/.bashrc
$ source ~/.bashrc
$ whereis sl
sl: /home/dobc/local/bin/sl
$ sl

grep
which
tar
cd
./configure --prefix=$HOME/local/
make
make install
hash -r
which
grep
$ grep --version
grep (GNU grep) 2.20
$ which grep
alias grep='grep --color=auto'
        /usr/bin/grep
$ wget http://mirrors.kernel.org/gnu/grep/grep-3.1.tar.xz
$ tar -Jxvf grep-3.1.tar.xz
$ cd grep-3.1
$ ./configure --prefix=$HOME/local/
$ make
$ make install
$ hash -r
$ grep --version
grep (GNU grep) 3.1
$ which grep
alias grep='grep --color=auto'
        ~/local/bin/grep

$ git config --global user.name "My Name"
$ git config --global user.email "myself@gmail.com"
$ git config --global core.editor "nano"

$ mkdir my-project
$ cd my-project    # Always run `git init` inside of a project folder!
$ git init         # Never inside of your home directory.

$ touch newfile.txt
$ git add newfile.txt
$ git commit  # Edit message in Nano, save the file, exit to commit.

$ git status

$ git log

#Note the `*` which indicates the current branch
$ git checkout -b "new-branch"
$ git branch
master
* new-branch

$ git checkout -b "add-awesome-feature"

$ echo "Some awesome text" > awesomefile.txt
$ git status
# On branch add-awesome-feature
# Untracked files:
...
#         awesomefile.txt
...

$ git add awesomefile.txt
$ git commit -m "Short awesome commit message"

$ git diff master

diff --git a/awesomefile.txt b/awesomefile.txt
new file mode 100644
index 0000000..08cec7f
--- /dev/null
+++ b/awesomefile.txt
@@ -0,0 +1 @@
+Some awesome text

$ git checkout master
$ git merge add-awesome-feature
Updating 459de26..5c4ca48
Fast-forward
awesomefile.txt | 1 +
1 file changed, 1 insertion(+)
create mode 100644 awesomefile.txt

$ cd /path/to/my/projects
$ git clone <some git url>
$ cd <new repo directory>
$ ls

$ cd ~
$ git clone https://github.com/DevOpsBootcamp/tinsy-flask-app.git
$ cd tinsy-flask-app

tinsy-flask-app
#Setup python virtual environment
$ virtualenv venv
$ source venv/bin/activate
(venv) $ pip install -r requirements.txt
#Run server
(venv) $ python script.py
#When finished, deactivate virtual environment
(venv) $ deactivate
$

function f(x):
    # This line is a comment, not run by the computer.
    # Comments are only for human eyes.
    if x is less than than 5
        print "x is less than 5"
    else if x is less than than 10
        print "x is greater than five and less than 10"
    else
        print "x is greater than 10"

>>> x = "value"
>>> print(x)
value
>>> x = "different value"
>>> print(x)
different value

if some conditional statement is true
    do something
else if some other conditional
    do something else
else
    do a final thing

for every element, let's call it "foo", in a list "my_list"
    if foo is greater than five
        print(foo)
    else
        print(foo + " is too small")

>>> user_input = get_input("Where would you like to go today? ")
>>> -> Where would you like to go today? Nebraska
>>> print(user_input)
>>> -> nebraska
>>> print(reverse(user_input))
>>> -> aksarben

function read_file(x):
    # Also check that it exists! How convenient!
    if file_exists(x)
        v = read_file_to_string(x)
        return v
    else
        print("file does not exist")
        return Null

struct dog {
    breed: String
    height: Float
    color: String
    age: Integer
}

spot = struct dog      # Create a new variable of type `struct dog`
spot.breed = "corgie"  # Assign each member a variable.
spot.height = 1.5
spot.color = "Blond"
spot.age = 1
print(spot.breed, spot.height, spot.color, spot.age)

class chair():
    function init(material):
        self.material = material

    function rock():
        print("The ", self.material, " chair rocks slowly.")

>>> my_chair = chair.init("plastic")
>>> my_chair.rock()
>>> -> The plastic chair rocks slowly.

import math_lib

print(math_lib.pi, math_lib.pow(2, 5), math_lib.tan(79.3))
# prints out "3.14 32 .951"

for
$ sudo <apt or yum> install python

True
7
18,446,744,073,709,551,615
12.4
"Hello World!"
['first', 'second']
{'key1': 'value', 'key2', 'value2'}
('value','paired value')
anObjects.variable == <value>
# This is a comment
boolean = True # boolean
name = "Lucy" # string
age = 20 # integer
pi = 3.14159 # float
alphabet = ['a', 'b', 'c']
dictionary = {"pi":3.14159, "sqrt 1":1}
winter = ('December', 'January', 'February', 'March')

print(name + " is " + str(age+1) + " this " winter[3])

$ python
>>> print("I'm in a REPL!")
>>> name =      # <Your name>
>>> age =       # <Your age>
>>> print(name + " is " + str(age))
>>> # We need to convert age from int to string so it can print!

if name == "Lucy":
    for month in winter:
        print name + " doesn't like " + month
else:
    print "My name isn't Lucy!"

def myfunction(arg1, arg2):
    return arg1 + arg2

print myfunction(1, 5)

from math import pi
x = pi

from math import *
x = pi

$ sudo apt-get install python-virtualenv
$ sudo yum install

# In each project you work on, you'll want to run
$ virtualenv venv
$ source venv/bin/activate
(venv)$ pip install <package>
(venv)$ deactivate

TODO
@app.route('/accounts/<account_name>', methods=['DELETE'])
def delete_account(account_name):
    if authenticated() and authorized():
        database.remove_account(account_name)
        return 'Success', 200
    else
        return 'Failure', 401

<!DOCTYPE HTML>
<html>

    <head>
        <title>Template Example</title>
    </head>

    <body>
        <p>Your lucky number today is {{ number }}!</p>
    </body>

</html>

render_template("template.html", number=random.randint(0, 99))

Your lucky number today is 42!

...
<body>
{% for message in messages %}
    <p>{{ message }}</p>
{% endfor %}
</body>
...

messages = ["Welcome!", "Test Message", "Vim > Emacs"]

render_template("template2.html", messages=messages)

Welcome!
Test Message
Vim > Emacs

GET http://web.site/page.html HTTP/1.1

HTTP/1.1 200 OK
Content-Type: text/html
...
<!DOCTYPE HTML>
...

def add_double(x, y):
    return 2*(x+y)

def test_add_double():
    expect(add_double(1, 2) == 6)

$ run tests
Finding tests...
Running tests in tests/foo.ext
Running tests in tests/bar.ext
Running tests in misc/test_baz.ext

var = some_function(x)
if var == expected_output:
    continue
else
    print("Test X failed!")

$ run test
Test 5 failed!

def simple_test():
    expect(some_function(x), expected_output)

$ run tests
....x.....
Test 5 failed.
Debug information:
...

def tests_setup():
    connect to database
    populate database with test data

def tests_teardown():
    delete all data from test database
    disconnect from database

def some_test()
    setup is called automatically
    use data in database
    assert something is true
    teardown is run automatically

unittest
+-----------+----------------------------------------+
| username: | admin                                  |
+-----------+----------------------------------------+
| password: | pass' || true); DROP TABLE STUDENTS;-- |
+-----------+----------------------------------------+

<img onerror=alert("Tracking your IP with a GUI interface!");>

<img src="http://example.com/?action="Delete All Accounts">

<Table 1>
+---------------+-----------+-----------+
| <Primary key> | <Field 1> | <Field 2> |
+---------------+-----------+-----------+
| 1             | value     | value`    |
| ...           | ...       | ...       |
+---------------+-----------+-----------+

<Table 2>
+---------------+-----------+--------------------------+
| <Primary key> | <Field 1> | <Foreign key to Table 1> |
+---------------+-----------+--------------------------+
| 1             | val       | 7                        |
| ...           | ...       | ...                      |
+---------------+-----------+--------------------------+

<Table 1>
+------------------+------------------+
| <Name>           | <Major>          |
+------------------+------------------+
| Linus Torvalds   | Computer Science |
| Richard Stallman | Computer Science |
+------------------+------------------+
<Table 2>
+------------------+--------------+----------------+
| <Major>          | <School>     | <Advisor Name> |
+------------------+--------------+----------------+
| Computer Science | Engineering  | Dennis Ritchie |
+------------------+--------------+----------------+
<Table 1> JOIN <Table 2>
+------------------+------------------+-------------+----------------+
| <Name>           | <Major>          | <School>    | <Advisor Name> |
+------------------+------------------+-------------+----------------+
| Linus Torvalds   | Computer Science | Engineering | Dennis Ritchie |
| Richard Stallman | Computer Science | Engineering | Dennis Ritchie |
+------------------+------------------+-------------+----------------+

CREATE TABLE nobel (
    id int(11)
        NOT NULL
        AUTO_INCREMENT,
    yr int(11),
    subject varchar(15),
    winner varchar(50)
)
ENGINE = InnoDB;

from django.db import migrations, models

class Migration(migrations.Migration):
    dependencies = [
        ('app', '0001_initial')
    ]

    operations = [
        migrations.AddField("Nobel", "topic", models.CharField(80))
    ]

SELECT
    yr, subject, winner
FROM
    nobel
WHERE
    yr = 1960 AND subject='medicine';

+------+------------+-------------------------------+
| yr   | subject    | winner                        |
+------+------------+-------------------------------+
| 1960 | "medicine" | "Sir Frank Macfarlane Burnet" |
| 1960 | "medicine" | "Sir Peter Brian Medawar"     |
+------+------------+-------------------------------+

INSERT INTO
    nobel
VALUES
    ('2013','Literature','Herta Müller');

+-----+------+--------------+----------------+
| id  | yr   | subject      | winner         |
+-----+------+--------------+----------------+
| ... | ...  | ...          | ...            |
| 873 | 2013 | "Literature" | "Herta Müller" |
| ... | ...  | ...          | ...            |
+-----+------+--------------+----------------+

UPDATE
    nobel
SET
    winner='Andrew Ryan'
WHERE
    subject='Peace' AND yr='1951';

+-----+------+---------+----------------+
| id  | yr   | subject | winner         |
+-----+------+---------+----------------+
| ... | ...  | ...     | ...            |
| 120 | 1951 | "Peace" | "Andrew Ryan"  |
| ... | ...  | ...     | ...            |
+-----+------+---------+----------------+

DELETE FROM
   nobel
WHERE
   yr = 1989 AND subject = 'peace';

SELECT winner FROM nobel
WHERE yr=1952 AND subject='medicine'; #(Selman A. Wksman)

SELECT * FROM nobel
WHERE yr=1903 AND subject='physics'; #(3)

SELECT * FROM nobel
WHERE winner='Linus Pauling'; #(2)

SELECT COUNT(*) FROM nobel
AS n0 INNER JOIN nobel AS n1 on n0.winner=n1.winner
AND (n0.yr!=n1.yr or n0.subject!=n1.subject); #(16)

nobel.sql.gz
# Create a table for Nobel prizes
$ mysqladmin -u root create nobel
# Get the database from the osl server
$ wget http://osl.io/nobel -O nobel.sql.gz
# Gunzip the file and import it into the nobel db
$ gunzip nobel.sql.gz
$ mysql nobel < nobel.sql
# OR do it in one step!
$ zcat nobel.sql.gz | mysql nobel
# Open up mysql shell to execute queries
$ mysql nobel

# List all the tables
SHOW TABLES;
# Print the layout of the database to the screen
DESCRIBE nobel;

mysql> SELECT subject, yr, winner FROM nobel
       WHERE yr=1960;

+------+------------+-----------------------------+
| yr   | subject    | winner                      |
+------+------------+-----------------------------+
| 1960 | Chemistry  | Willard F. Libby            |
| 1960 | Literature | Saint-John Perse            |
| ...  | ...        | ...                         |
+------+------------+-----------------------------+

nobel.py
#!/usr/bin/python
import MySQLdb
import os

db = MySQLdb.connect(
  os.environ['MYSQL_PORT_3306_TCP_ADDR'],
  'root',
  os.environ['MYSQL_ENV_MYSQL_ROOT_PASSWORD'],
  "nobel"
)

cursor = db.cursor()
cursor.execute("SELECT subject, yr, winner FROM nobel WHERE yr = 1960")
data = cursor.fetchall()

for winner in data:
    print "%s winner in %s: %s " % (winner[0], winner[1], winner[2])

db.close()

# SELECT * FROM nobel WHERE yr = 1960
for subject, yr, winner in session.query(Nobel).filter_by(yr=1960):
    print "%s winner in %s: %s " % (subject, yr, winner)

Ctrl+Shift+K
Command+option+k
Ctrl+Shift+I
Cmd+opt+I
flake8
rubocop
splint
jshint
src/times.js: line 407, col 20, Expected '{' and instead saw 'return'.
src/times.js: line 415, col 49, Missing semicolon.
src/times.js: line 407, col 58, 'error' is not defined.

Name                      Stmts   Miss  Cover   Missing
-------------------------------------------------------
my_program.py                20      4    80%   33-35, 39
my_other_module.py           56      6    89%   17-23
-------------------------------------------------------
TOTAL                        76     10    87%

$ virtualenv <virtualenv name>
New python executable in /path/to/<venv name>/bin/python
Installing setuptools, pip, wheel...
done.
$ source <venv name>/bin/activate

(<venv name>) $ pip install flask
[...]

(<venv name>) $ pip freeze
click==6.7
Flask==1.0.2
itsdangerous==0.24
Jinja2==2.10
MarkupSafe==1.0
Werkzeug==0.14.1

(<venv name>) $ deactivate
$

node_modules
package.json
Cargo.toml
target
MIT         1
Yale        2
Harvard     3
ATT         4
...

...
joeBillson  14895
susan-gill  15832
...

devopsbootcamp.osuosl.org.
.
root
root
org
org
osuosl
osuosl
devopsbootcamp
A
osuosl.org.     300 IN  A   140.211.15.183

MX
osuosl.org.     3600    IN  MX  5 smtp3.osuosl.org.
osuosl.org.     3600    IN  MX  5 smtp4.osuosl.org.
osuosl.org.     3600    IN  MX  5 smtp1.osuosl.org.
osuosl.org.     3600    IN  MX  5 smtp2.osuosl.org.

NS
osuosl.org.     86258   IN  NS  ns1.auth.osuosl.org.
osuosl.org.     86258   IN  NS  ns2.auth.osuosl.org.
osuosl.org.     86258   IN  NS  ns3.auth.osuosl.org.

SOA
osuosl.org.     86400   IN  SOA ns1.auth.osuosl.org. ...

CNAME
bar.example.com.  86400  IN  CNAME  foo.example.com

Host something.invalid.osuosl.org not found: 3(NXDOMAIN)

$ dig ns .
;; ANSWER SECTION:
.           512297  IN  NS  i.root-servers.net.
.           512297  IN  NS  e.root-servers.net.
.           512297  IN  NS  d.root-servers.net.
.           512297  IN  NS  j.root-servers.net.
.           512297  IN  NS  b.root-servers.net.
.           512297  IN  NS  a.root-servers.net.
.           512297  IN  NS  f.root-servers.net.
.           512297  IN  NS  h.root-servers.net.
.           512297  IN  NS  g.root-servers.net.
.           512297  IN  NS  c.root-servers.net.
.           512297  IN  NS  m.root-servers.net.
.           512297  IN  NS  k.root-servers.net.
.           512297  IN  NS  l.root-servers.net.

dig
dig @server name type

dig @ns1.osuosl.org osuosl.org A

.
$ dig ns .
;; QUESTION SECTION:
;.              IN  NS

;; ANSWER SECTION:
.           518400  IN  NS  i.root-servers.net.
.           518400  IN  NS  a.root-servers.net.
.           518400  IN  NS  l.root-servers.net.
.           518400  IN  NS  f.root-servers.net.
.           518400  IN  NS  b.root-servers.net.

etc...

NS
org.
$ dig ns com. @a.root-servers.net
;; QUESTION SECTION:
;org.               IN  NS

;; AUTHORITY SECTION:
org.            172800  IN  NS  a0.org.afilias-nst.info.
org.            172800  IN  NS  a2.org.afilias-nst.info.

etc...

;; ADDITIONAL SECTION:
a0.org.afilias-nst.info. 172800 IN  A   199.19.56.1

etc...

NS
osuosl.org.
$ dig ns osuosl.org. @199.19.56.1
;; QUESTION SECTION:
;osuosl.org.            IN  NS

;; AUTHORITY SECTION:
osuosl.org.     86400   IN  NS  ns3.auth.osuosl.org.
osuosl.org.     86400   IN  NS  ns2.auth.osuosl.org.
osuosl.org.     86400   IN  NS  ns1.auth.osuosl.org.

;; ADDITIONAL SECTION:
ns1.auth.osuosl.org.    86400   IN  A   140.211.166.140
ns2.auth.osuosl.org.    86400   IN  A   140.211.166.141
ns3.auth.osuosl.org.    86400   IN  A   216.165.191.53

A
osuosl.org.
$ dig a osuosl.org. @140.211.166.140
;; QUESTION SECTION:
;osuosl.org.            IN  A

;; ANSWER SECTION:
osuosl.org.     300 IN  A   140.211.15.183

;; AUTHORITY SECTION:
osuosl.org.     86400   IN  NS  ns1.auth.osuosl.org.
osuosl.org.     86400   IN  NS  ns2.auth.osuosl.org.
osuosl.org.     86400   IN  NS  ns3.auth.osuosl.org.

;; ADDITIONAL SECTION:
ns1.auth.osuosl.org.    86400   IN  A   140.211.166.140
ns2.auth.osuosl.org.    86400   IN  A   140.211.166.141
ns3.auth.osuosl.org.    3600    IN  A   216.165.191.53

dig
dig
dig
user { 'audience':
    ensure  => present,
}

packages [nginx, python, vim]
    state installed
    update true

service nginx
    state enabled
    alert service myapp_daemon

package "apache" do
  package_name "httpd"
  action :install
end

service "apache" do
  action [:enable, :start]
end

package { "apache":
  name    => "httpd",
  ensure  => present,
}

service { "apache":
  name    => "apache",
  ensure  => running,
  enable  => true,
  require => Package["apache"],
}

- hosts: all
  tasks:

    - name: Install Apache
      yum:
        name: httpd
        state: present

    - name: Start Apache Service
      service:
        name: httpd
        state: running
        enabled: yes

[vm] # ps aux
USER PID %CPU %MEM    VSZ   RSS TTY STAT START   TIME COMMAND
root   1  0.0  0.6 110564  3164 ?   Ss    2015  11:17 /lib/systemd/systemd --system --deserialize 15
root   2  0.0  0.0      0     0 ?   S     2015   0:00 [kthreadd]
root   3  0.0  0.0      0     0 ?   S     2015   3:55 [ksoftirqd/0]
root   5  0.0  0.0      0     0 ?   S<    2015   0:00 [kworker/0:0H]
[... 120+ more lines ...]

[host] # ps aux
USER  PID %CPU %MEM    VSZ   RSS TTY STAT START   TIME COMMAND
root    1  0.0  0.1 200328  5208 ?   Ss   Aug25   0:44 /sbin/init
root    2  0.0  0.0      0     0 ?   S    Aug25   0:00 [kthreadd]
root    3  0.0  0.0      0     0 ?   S    Aug25   0:05 [ksoftirqd/0]
root    5  0.0  0.0      0     0 ?   S<   Aug25   0:00 [kworker/0:0H]
[... 240+ more lines ...]

[container] $ ps aux
PID   USER     TIME   COMMAND
1     root     0:00   sh
6     root     0:00   ps aux

chroot
irc.freenode.net
#devopsbootcamp
#devopsbootcamp
$ git clone https://github.com/DevOpsBootcamp/Bootcamp-Exercises.git

$ cd Bootcamp-Exercises
$ docker-compose up -d
$ docker-compose run -p 8080:8080 dobc bash

exit
$ docker-compose kill
$ docker-compose rm --all

ls -l
sl
sl
grep
grep
unittest
dig

Description	Slot 1	Slot 2
Lab #1	Oct 31, 2018 10am-12pm	Nov 1, 2018 2-4pm
Lab #2	Nov 14, 2018 10am-12pm	Nov 15, 2018 2-4pm
Lab #3	Nov 28, 2018 10am-12pm	Nov 29, 2018 2-4pm

Command	Description
`/list`	Reports all the channels on a server.
`/topic`	Reports current channel topic.
`/names`	Reports nicks of users in channel.
`/join <channel>`	Join a new channel.
`/whois <nick>`	Learn about a person.
`/msg`	Directly message an individual.
`/help <command>`	Provides help for commands

Term	Description
channel	Chat rooms with with ‘#’ prefixed in front of their names
ping/pong	‘I would like to tell you something.’ / ‘I’m here, tell it to me.’
tail	~
hat	‘@’ Denotes admin status in a channel.
nick	Your name.
netsplit	When the IRC servers lose connection with each other.
kick/ban/k-line	Force someone off the channel or server, typically for abuse

`sh`	Required by all POSIX Operating Systems.
`bash`	Default on most GNU/Linux-based Operating Systems.
`csh`	Default shell on most BSD (Unix) based Operating Systems
`zsh`	The hip new shell on the block.
`fish`	Yet another hip new shell on the block.

Variable	Meaning
`$*`	All arguments passed
`$?`	Return code of last command run
`"$@"`	All arguments passed as a list
`$CDPATH`	Colon-delimited list of places to look for dirs
`$HOME`	Location of user homedir
`$IFS`	Internal Field Seperator
`$OLDPWD`	Previous PWD

Variable	Meaning
`$PATH`	Colon-delimited list of places to find executables
`$PWD`	Present Working Directory
`$SHELL`	Path to running shell
`$UID`	User ID
`$USER`	Username

`.`	The current directory
`..`	The parent directory
`~`	Alias for your home directory
`/`	Separates directories: `one_dir/another_dir/last_dir` Alone, or at the start of a path, it is the root directory.

Owner	atime, ctime, mtime
Group	POSIX ACLs
Permissions	Spinlock
Inode	i_ino
Size	read, write and link count
Filename

Type	Example
boolean	`True`
integer	`7`
long	`18,446,744,073,709,551,615`
float	`12.4`
string	`"Hello World!"`
list	`['first', 'second']`
dict (map)	`{'key1': 'value', 'key2', 'value2'}`
tuple	`('value','paired value')`
object	`anObjects.variable == <value>`
None

Acronym	Name
A, AAAA	IP Addresses
MX	SMTP Mail Exchangers
NS	Name Servers
SOA	DNS Zone Authority
PTR	Pointers for Reverse DNS Lookups
CNAME	Domain Name Aliases

Virtual Machines	Containers
Complete process isolation	Fast startup
‘Battle Tested’	Little overhead

Virtual Machines	Containers
Slightly more overhead.	Security concerns.
Slow startup.	No cross-kernel emulation.
Cross-kernel emulation.

Virtual Machines	Containers
VirtualBox	Docker
VMWare	Rkt

Navigation

DevOps BootCamp¶

Ready to Learn DevOps? Lesson 0: Start Here¶

DevOps BootCamp: Fall 2018¶

DevOps Open Office Labs¶

Schedule¶

Fall¶

Open Office Labs¶

Donate¶

Lesson 0: Start Here¶

About the Program¶

Definition: System Administration¶

Definition: System Engineers¶

Definition: DevOps Engineers¶

Definition: Site Reliability Engineers (SRE)¶

DevOps¶

What DevOps BootCamp (DOBC) is¶

What DOBC is not¶

Why DOBC Exists¶

What You Will do¶

Who Teaches DOBC¶

Bi-Weekly Open Office Labs¶

The ‘Agreement’¶

Getting Involved¶

Lesson 1: First Steps¶

Vocabulary¶

Exercise: What Vocabulary Do You Know?¶

Notation¶

Exercise: Reading Examples¶

Answer: Reading Examples¶

SSH: Secure Shell¶

Getting Setup on Linux¶

Docker Setup¶

Virtual Machine Setup¶

Windows Subsystem for Linux Setup¶

Exercise: Change Your Password!¶

Further Reading¶

Lesson 2: Operating Systems¶

What an Operating System is¶

Anatomy of an OS¶

Types of Operating Systems¶

Popular Operating Systems¶

GNU/Linux¶

Flavors of Linux¶

Exercise: Pop Quiz¶

Further Reading¶

Lesson 3: Docs & Communication¶

When in doubt¶

Man Pages¶

Anatomy of a Man Page¶

Sections of Man¶

Project Docs¶

Communication¶

IRC¶

Exercise: Getting on IRC¶

Other IRC Clients¶

Connecting and Setup¶

Commands and Tips¶

IRC Jargon¶

Slack¶

Asking for Help¶

Further Reading¶

Lesson 4: Shell Navigation¶

The Shell¶

Shell Examples¶

Navigation Concepts¶

Basic Shell Commands¶

Shell Scripts¶

Useful Symbols¶

More Useful Symbols¶

Combining These Together¶

Function Definitions¶

Internal Variables¶

Internal Variables¶

File Paths¶

Special Characters¶

Type Less, Tab More¶

Text Editor: Nano¶

Bash Hello World¶

Passing arguments to the bash script¶

Finding Metadata with `ls -l`¶

Exercise: Install `sl`¶

Answer: Install `sl`¶

Exercise: Install `grep`¶

Answer: Install `grep`¶