1. Backing up a machine with git
St. Louis Unix User's Group 13 April 2016
Lee Lammert
Omnitec Corporation
SLUUG 13 April 2016

2. so, what’s git?
A distributed revision control system with an emphasis on:
Speed
Data integrity
Support for distributed, non-linear workflows
Initially designed and developed in 2005 by Linus Torvalds and the Linux kernel developers
SLUUG 13 April 2016

3. Git is distributed version control system focused on speed, effectivity and real-world usability on large projects.
- git-scm.com
SLUUG 13 April 2016

4. git is, .. Directory content management system
Tree history storage system
A toolkit
Stupid content tracker
The “plumbing”!
SLUUG 13 April 2016

5. Basic source control system
SLUUG 13 April 2016

6. but why git?
SLUUG 13 April 2016

7. let’s git started
SLUUG 13 April 2016

8. Create a repository $ cd (project-directory) $ git init
Initialized empty Git repository in .git/
$ gs
On branch master
Initial commit
nothing to commit (create/copy files and use "git add" to track)
SLUUG 13 April 2016

9. What was that?
Being old-school cli, I am a firm believer that the fewer characters the better:
alias gs='git status'
alias gd='git diff'
SLUUG 13 April 2016

10. Add some files $ touch lee $ touch bob $ touch steve $ gs
On branch master
Initial commit
Untracked files:
(use "git add <file>..." to include in what will be committed)
bob
lee
steve
nothing added to commit but untracked files present (use "git add" to track)
$ git add *
SLUUG 13 April 2016

11. Add them to the repo $ git commit -m "Initial Version"
[master (root-commit) a037529] Initial Version
3 files changed, 0 insertions(+), 0 deletions(-)
create mode bob
create mode lee
create mode steve
$ gs
On branch master
nothing to commit, working directory clean
SLUUG 13 April 2016

12. Change something $ gs On branch master Changes not staged for commit:
(use "git add <file>..." to update what will be committed)
(use "git checkout -- <file>..." to discard changes in working directory)
modified: lee
Untracked files:
(use "git add <file>..." to include in what will be committed)
lee~
no changes added to commit (use "git add" and/or "git commit -a")
$ git commit -m "Initial Version"
[master (root-commit) a037529] Initial Version
3 files changed, 0 insertions(+), 0 deletions(-)
create mode bob
create mode lee
create mode steve
$ gs
On branch master
nothing to commit, working directory clean
SLUUG 13 April 2016

13. Need to ignore some files!
$ cat .gitignore *~
$ git commit .gitignore -m "Added .gitignore"
[master ae5e55b] Added .gitignore
1 file changed, 1 insertion(+)
create mode gitignore
$ gs
On branch master
Changes not staged for commit:
(use "git add <file>..." to update what will be committed)
(use "git checkout -- <file>..." to discard changes in working directory)
modified: lee
no changes added to commit (use "git add" and/or "git commit -a")
SLUUG 13 April 2016

14. Look at changes git diff alias gd='git diff' $ gd lee
diff --git a/lee b/lee
index e69de29..3c73ecc
--- a/lee
+++ b/lee
-0,0 +1
+This is a changed file!
SLUUG 13 April 2016

15. Two ways to add files Adding a individual file Adding a multiple files
$ git add README
Adding a multiple files
$ git add .
SLUUG 13 April 2016

16. Check the history $ git log
commit ae5e55bce726b35f62ae945a2a52705f99ecb5cf
Author: L. V. Lammert
Date: Wed Apr 13 15:33:
Added .gitignore
commit a adbae38abb64ffcc15ba cae1
Date: Wed Apr 13 15:28:
Initial Version
SLUUG 13 April 2016

17. Configuring the repo $ git config --global user.name "L V Lammert"
$ git config --global user.
SLUUG 13 April 2016

18. So, .. what about this backup thing?
git operates in the current directory
Unlimited versions, changes, tracking, tags, collaboration uses the repo
BUT, a repo is not saved anywhere else!
SLUUG 13 April 2016

19. Local .git directory $ ls -al .git total 24
drwxrwxr-x 8 lvl users 155 Apr 13 15:34 ./
drwxrwxr-x 3 lvl users 77 Apr 13 15:32 ../
drwxrwxr-x 2 lvl users 6 Apr 13 15:19 branches/
-rw-rw-r-- 1 lvl users 17 Apr 13 15:33 COMMIT_EDITMSG
-rwxrw-r-- 1 lvl users 92 Apr 13 15:19 config*
-rw-rw-r-- 1 lvl users 73 Apr 13 15:19 description
-rw-rw-r-- 1 lvl users 23 Apr 13 15:19 HEAD
drwxrwxr-x 2 lvl users 4096 Apr 13 15:19 hooks/
-rw-rw-r-- 1 lvl users 328 Apr 13 15:33 index
drwxrwxr-x 2 lvl users 20 Apr 13 15:19 info/
drwxrwxr-x 3 lvl users 28 Apr 13 15:28 logs/
drwxrwxr-x 10 lvl users 82 Apr 13 15:33 objects/
drwxrwxr-x 4 lvl users 29 Apr 13 15:19 refs/
SLUUG 13 April 2016

20. Create a remote copy Setup a keypair for access, and test
Init the repo there
$ ssh apollo
Last login: Wed Apr 13 12:28: from marvel.omnitec.net
OpenBSD 4.8 (GENERIC) #136: Mon Aug 16 09:06:23 MDT 2010
(-bash)
$ mkdir SLUUG_Repo
$ git init --bare
Initialized empty Git repository in /u/lvl/
SLUUG 13 April 2016

21. Connect your repo Add a remote to the local repo
$ git remote add SLUUG apollo:SLUUG_repo
$ git remote
SLUUG
SLUUG 13 April 2016

22. push local to remote $ git push SLUUG master
Counting objects: 6, done.
Delta compression using up to 6 threads.
Compressing objects: 100% (4/4), done.
Writing objects: 100% (6/6), 483 bytes | 0 bytes/s, done.
Total 6 (delta 0), reused 0 (delta 0)
To apollo:SLUUG_Repo
* [new branch] master -> master
$ git push SLUUG master
Counting objects: 6, done.
Delta compression using up to 6 threads.
Compressing objects: 100% (4/4), done.
Writing objects: 100% (6/6), 483 bytes | 0 bytes/s, done.
Total 6 (delta 0), reused 0 (delta 0)
To apollo:SLUUG_Repo
* [new branch] master -> master
SLUUG 13 April 2016

23. more git uses Undoing changes Checkout a specific version
$ git checkout lee
$ git checkout
d20c7a295965f798109f9d4af0fbeedd8 <file name>
SLUUG 13 April 2016

24. developing parallel with branching

25. create a branch $ git checkout -b bugfix
Switched to a new branch “bugfix”

26. switching branches $ git status $ git checkout master
# On branch bugfix
nothing to commit (working directory clean)
$ git checkout master
Switched to branch “master”

27. collaborating with git

28. public repos = free
private repos = cheap

29. clone a hosted repository
$ git clone git://github.com/git/hello-world.git
Initialized empty Git repository in /Users/me/Projects/hello-world/.git/
remote: Counting objects: 158, done.
remote: Compressing objects: 100% (79/79), done.
remote: Total 158 (delta 54), reused 157 (delta 54)
Receiving objects: 100% (158/158), KiB, done.
Resolving deltas: 100% (54/54), done.
$ cd hello-world

30. pull changes (and pull often)
$ git pull origin master

31. add changes to master
$ git checkout master
$ git merge bugfix

32. push changes
$ git push origin master

33. configure & customize git

34. add pretty colors $ git config --global color.diff auto
$ git config --global color.status auto
$ git config --global color.branch auto

35. git tools

36. gitk

37. GitX

38. TortoiseGit

39. git resources

40. Pro Git (book)

41. Pragmatic Version Control Using Git (book)

42. Git Community Book

43. Git Cheat Sheet

44. what to remember commit often pull often
use checkout and reset with caution
create your own repository anywhere

45. fin

46. linkedin.com/in/erincarter
illustrations by Simon Oxley of idokungfood.com
theme inspired by Scott Chacon’s git-scm.com