vitbyst

System Design Cheatsheet

Picking the right architecture = Picking the right battles + Managing trade-offs

Basic Steps

Clarify and agree on the scope of the system

User cases (description of sequences of events that, taken together, lead to a system doing something useful)
- Who is going to use it?
- How are they going to use it?

Typing vagrant from the command line will display a list of all available commands.

Be sure that you are in the same directory as the Vagrantfile when running these commands!

Creating a VM

vagrant init -- Initialize Vagrant with a Vagrantfile and ./.vagrant directory, using no specified base image. Before you can do vagrant up, you'll need to specify a base image in the Vagrantfile.
vagrant init <boxpath> -- Initialize Vagrant with a specific box. To find a box, go to the public Vagrant box catalog. When you find one you like, just replace it's name with boxpath. For example, vagrant init ubuntu/trusty64.

Starting a VM

vagrant up -- starts vagrant environment (also provisions only on the FIRST vagrant up)

I have two user accounts set up on my mac. User drew I use for most things, but if I'm making a screencast I'll switch to the demo user. I know that the demo user has a clean desktop, and the font size is larger than usual in my terminal and text editors, making everything a bit more legible when capturing the screen. When I record a screencast as the demo user, I save the file to /Users/Shared/screencasts. As I understand it, the /Users/Shared directory is supposed to be accessible to all user accounts on the mac. If I created and saved a screenflow document as the demo user, I should be able to read and write that file when logged in as user drew.

That was the theory, but it didn't always work out that well in practice. I would occasionally find that a directory was only writable by one user or the other. Perhaps I'd open a screenflow document as user drew and attempt to export the video to the same directory, only to find that the directory was owned by demo, meaning that I couldn't cr

Each of these commands will run an ad hoc http static server in your current (or specified) directory, available at http://localhost:8000. Use this power wisely.

Discussion on reddit.

Python 2.x

$ python -m SimpleHTTPServer 8000

	#cloud-config
	package_upgrade: true
	packages:
	- zsh
	- tmux
	- nmap
	- curl
	- wget
	- git
	- htop

	1) Create a branch with the tag
	git branch {tagname}-branch {tagname}
	git checkout {tagname}-branch

	2) Include the fix manually if it's just a change ....
	git add .
	git ci -m "Fix included"
	or cherry-pick the commit, whatever is easier
	git cherry-pick {num_commit}

	Go to Bitbucket and create a new repository (its better to have an empty repo)
	git clone [email protected]:abc/myforkedrepo.git
	cd myforkedrepo

	Now add Github repo as a new remote in Bitbucket called "sync"
	git remote add sync [email protected]:def/originalrepo.git

	Verify what are the remotes currently being setup for "myforkedrepo". This following command should show "fetch" and "push" for two remotes i.e. "origin" and "sync"
	git remote -v

	if ! type "brew" > /dev/null; then
	ruby -e "$(curl -fsSL https://raw.github.com/Homebrew/homebrew/go/install)";
	fi
	brew tap phinze/homebrew-cask && brew install brew-cask;
	brew cask install vagrant;
	brew cask install virtualbox;

	## Configure eth0
	#
	# vi /etc/sysconfig/network-scripts/ifcfg-eth0

	DEVICE="eth0"
	NM_CONTROLLED="yes"
	ONBOOT=yes
	HWADDR=A4:BA:DB:37:F1:04
	TYPE=Ethernet
	BOOTPROTO=static