So what the heck does that mean? We’re making it possible for you (and various programs on your computer) do the following:

$ echo "Hello!" | mail -s "This is cool" tom # Sent to /var/mail/tom spool
$ echo "Hello!" | mail -s "This is cool" tom@tompurl.com # Sent to my Gmail account

So now you may be asking yourself “why anyone would want to so something like this on a desktop machine that isn’t a mail server? Can’t you just send email using programs like the Gmail web client and Thunderbird?”. You certainly can, but it’s not always the best choice.

For example, it you wanted to send an email message from a shell script, the easiest way to do that is to use the mail command above. Also, your system may want to send you a message if something weird happens, like a failed cronjob. Without a working mail server like Exim installed and configured, those messages are going to end up in /dev/null.

So let’s get started

exim4-base                4.74-1ubuntu1.2
exim4-config              4.74-1ubuntu1.2
exim4-daemon-light        4.74-1ubuntu1.2
libmailutils2             1:2.1+dfsg1-7build1
mailutils                 1:2.1+dfsg1-7build1
mutt                      1.5.21-2ubuntu3

$ sudo apt-get install exim4-base mailutils mutt

$ sudo dpkg-reconfigure exim4-config

$ chown root:Debian-exim /etc/exim4/passwd.client

*.google.com:tom@tompurl.com:somethingClever

# Please replace "me" with your user account name and verify in mutt
$ echo test | mail -s "test" me # Sends mail to /var/mail/me spool
# Please replace "me@gmail.com" with your actual Gmail address
$ echo test | mail -s "test" me@gmail.com # verify using Gmail

————————–

This tutorial shows you how I installed Graphite, a fantastic tool for for visualizing time-series data, on an Ubuntu 10.4 LTS system. The process is split up into 4 steps:

• Installing and testing Graphite and Carbon in “dev” mode
• Integrating Graphite with Apache
• Making Carbon a managed service
• Password-protecting your Graphite site

$ sudo apt-get install bzr python-cairo python-django

$ cd ~/src
$ bzr branch lp:graphite
$ cd graphite
$ python ./setup.py build
$ sudo python ./setup.py install

$ cd ~/src/graphite/whisper
$ python ./setup.py build
$ sudo python ./setup.py install

$ cd ~/src/graphite/carbon
$ python ./setup.py build
$ sudo python ./setup.py install

$ cd /opt/graphite/conf
$ sudo cp carbon.conf.example carbon.conf
$ sudo cp storage-schemas.conf.example storage-schemas.conf

$ cd /opt
$ sudo chown -R myid:myid grahite

$ cd /opt/graphite
$ PYTHONPATH=`pwd`/webapp:`pwd`/whisper python ./webapp/graphite/manage.py syncdb

$ echo DEBUG = True > /opt/graphite/webapp/graphite/local_settings.py

$ cd /opt/graphite
$ PYTHONPATH=`pwd`/whisper ./bin/run-graphite-devel-server.py --libs=`pwd`/webapp/ /opt/graphite/

$ cd /opt/graphite
$ PYTHONPATH=`pwd`/whisper ./carbon/bin/carbon-cache.py --debug start

$ ~/src/graphite/examples/example-client.py

$ sudo apt-get install apache2 libapache2-mod-wsgi

$ cd ~/src/graphite/examples
$ cp example-graphite-vhost.conf graphite-vhost.conf

$ sudo cp graphite-vhost.conf /etc/apache2/sites-available
$ sudo a2ensite graphite-vhost.conf

$ cd /opt
$ sudo chown -R www-data:www-data grahite

$ sudo /etc/init.d/apache reload

10.0.0.100  web

10.0.0.100  web graphite

#! /bin/sh
# /etc/init.d/carbon

# Some things that run always
touch /var/lock/carbon

GRAPHITE_HOME=/opt/graphite
CARBON_USER=www-data

# Carry out specific functions when asked to by the system
case "$1" in
    start)
        echo "Starting script carbon "
        su $CARBON_USER -c "cd $GRAPHITE_HOME"; su $CARBON_USR -c "$GRAPHITE_HOME/bin/carbon-cache.py start"
        ;;
    stop)
        echo "Stopping script carbon"
        su $CARBON_USER -c "cd $GRAPHITE_HOME"; su $CARBON_USR -c "$GRAPHITE_HOME/bin/carbon-cache.py stop"
        ;;
    *)
        echo "Usage: /etc/init.d/carbon {start|stop}"
        exit 1
        ;;
esac

exit 0

$ sudo update-rc.d carbon defaults

# Set up .htaccess security so that I can protect the site online.
<Location "/">
    AuthType Basic
    AuthName "Under Construction"
    AuthUserFile /opt/graphite/sec/.mypasswds
    AuthGroupFile /opt/graphite/sec/.mygroups
    Require group managers
</Location>

$ cd /opt/graphite
$ sudo mkdir sec
$ sudo chown -R www-data:www-data ./sec
$ sudo htpasswd -c ./sec/.mypasswds some_user_name
(enter a strong password)
$ echo 'managers: tom' | sudo tee -a ./sec/.mygroups
$ sudo chmod -R 600 ./sec
$ sudo /etc/init.d/apache reload

• tompurl/Scrugar

Basically, it’s a couple of functions and aliases that I use to make it easier to use Screen. A few of my friends have found them to be pretty useful, so I decided to share them.

Posted from Diigo. The rest of my favorite links are here.

Posted from Diigo. The rest of my favorite links are here.

However, it always surprises me to see that very few other people use them. I therefore decided to put together a small tutorial on creating mind maps. I hope that it helps a few other people

What’s A Mind Map?

A mind map is a visualization of a brain dump. Sound weird? Here’s what I mean.

Often, when we are thinking about a big idea (e.g. how will I write this essay, should I pursue this business opportunity, etc.), we have lots of related ideas floating around in our heads. Trying to evaluate and flesh-out all of these ideas in our heads can be very difficult. First, focusing on one idea for a long time can cause you to forget about the other ideas. Second, it’s often hard to see the big picture as your big idea gets bigger and bigger.

So it helps if you can actually write all of these ideas down and organize them. The problem is that, in the US, we are trained to do this will a bulleted list. It’s still better than not writing down your ideas, but the format is not very conducive to organizing lots of little, loosely-related pieces of information.

Mind maps are a much better tool. They allow you to do the following

• Record your ideas
• Show how the ideas are related in a simple, lightweight and intuitive way
• See the big picture of your big idea.

So why would you need to use something like this? Here’s a few examples:

• Brainstorming Session (either by yourself or with a group)
• Writing
  • Mind maps are a great way to gather and organize information for an outline.

Mini-Tutorial

Ok, so how do you do it? Here’s a quick example. Let’s assume that you wanted to write a blog post about a great new recipe that you invented. You don’t know what to include and you don’t want to miss any important ideas, so you decide to create a mind map.

First, you need some way of recording your mind map. Some of the most useful mind maps that I have every created have been done with a piece of paper and a pencil. However, if I get a choice, I prefer using a program called Xmind. There’s a free version that is very powerful and easy to use.

Next, you need a main idea. This is the idea that is at the center of all of your other ideas. In this example, the main idea would be something like “Pulled Pork Blog Recipe”. You would then record your idea in your mind map like this:

Next, you’ll want to create some sub-nodes or subtopics. These are simply “child” nodes of the main idea. Here’s an example of what you may user for a blog article:

This is the “model” that you can now use to organize your thoughts. As you can see, it’s basically a stream of conciousness. Your version of this map would probably look a little different.

So now you can just create child nodes of the child nodes and let your mind wander. Here’s an example of a complete mind map that you might use for this type of blog post:

This format may seem a little strange to you, but that’s ok. Most of the time, mind maps will only be used by the owner, so they only have to make sense to the owner. So use the structure and format that works best for you.

Ok, so now you have a complete mind map. What can you do with it?

• Document: If the goal was to publish a document, then the mind map could either be that document or help you create that document. For example, you could use the outline node in the example above to help you write a blog post.
• Decision: Sometimes, the only thing that is “created” by a mind map is a decision. For example, I once had an idea for creating a web application that I would run as a side business. When the idea was in my head, it seemed great. However, once I got all of my ideas down into a mind map, it was clear to me that this idea had been done before and that the market was already saturated.

More On Formatting

Chances are that your mind is “wired” a little differently than anyone else’s mind. And since a mind map is usually a brain dump, your structure and format will be unique.

So in other words, don’t sweat the format Besides, if you are using a program like Xmind to create your map, then you have the freedom to move your nodes around if change your mind about the structure.

One final note on formatting. If you are creating a document that has to be published, then it probably isn’t a mind map, even if you use a mind-mapping tool like Xmind to create it. Mind maps are great for creating documents and ideas, not for communicating with large groups of people.

Resources

Here’s some documentation that can help you get started with mind-mapping.

• The mind map (.png, .xmind) that was used to create this blog post.
  • That’s right, I created a mind map to help me write my blog post about mind-mapping. Feel free to take a look!
• Software
  • Xmind
  • Freemind
  • There are loads of non-free mind-mapping tools, but I’ve never used one so I can’t comment on them.
• Web Sites
  • Xmind.net has some great examples of mind maps that users have uploaded. Check it out if you want to see what is possible.

Posted from Diigo. The rest of my favorite links are here.

“Facebook isn’t using HTTPS by default any more, so your PC might get HACKED!”

This message was very useful to many of my friend’s Facebook friends. Also, I’m a big fan of using HTTPS, so I’m glad that she was helping her friends have a more secure web browsing experience.

Statements like this, however, show that many smart, tech-savy and well-educated people are very confused by the concept of HTTPS. They don’t understand what it can and can’t do, which causes them to miss out on a lot of its benefits and expose themselves to threats.

I therefore decided to put together a simple, layman’s guide to using HTTPS. I hope that it will help clear some confusion.

Caveat

I am by no means a security expert, and I can’t guarantee that anything that you do online will be 100% safe. No system is perfect, and that includes HTTPS.

So who am I? I’m a systems engineer with 11 years of experience running large applications on top of complex systems. During that time, I’ve worked with a lot of web applications, and I have learned a thing or two about security. My knowledge is incomplete, but it’s complete enough to help a lot of my friends.

What Is HTTPS?

(The following is the scariest paragraph in this post. If it seems like a foreign language to you, that’s OK. Just keep reading and everything will be explained in English )

HTTPS stands for SSL over HTTP. HTTP is the protocol that your web browser uses to talk to web sites. SSL is a an application that is used to encrypt data. So HTTPS is a system for exchanging encrypted data between web browsers and web sites.

Ok, so what did all of that mean? Well, first let’s talk about HTTP. This is just the way that web browsers and web sites have agreed to talk to each other. That’s it. Nothing too fancy.

SSL (pronounced “ess-ess-ehl”) is a program for encryption, but what’s that? Well you can think of encryption as a way of turning data into gibberish that very few other people will be able to read. Encryption can be really simple, like Pig Latin, or incredibly sophisticated, like the encryption that your web browser users.

So HTTPS is the system that allows you to encrypt your secret information so that only you and your target web site (e.g. your bank’s web site, Facebook) can understand it. If anyone who is between your web browser and your target web site tries to intercept the traffic, they won’t be able to decipher it. This is the #1 benefit of HTTPS, and if you only read one paragraph in this article, I hope that it’s this one.

Now this concept really confused me when I first started learning about networking. Who on earth would read my internet traffic while it’s moving along the network? Well, there are points between your web browser and your target web site where third-parties could be intercepting your web traffic. These “points” are called hops, and there are an arbitrary number of them between your web browser and any web site that you may visit. The following are examples of hops:

• Your ISP’s servers
• Your employer’s firewall
• Your email provider
• The wireless access point that you’re using at the coffee house

Anyone who has access to any of these hops can potentially intercept your web traffic and read private things like passwords and cookie information. And if this traffic isn’t encrypted using something like SSL, then it’s trivially simple to do.

So that’s the number one reason why SSL is so awesome. But there’s one more great feature too. For a web site owner to use SSL, they need  to have a certificate installed on their servers that guarantees their identity. You can think of it like a driver’s license for web applications. This driver’s license ensures that yourbank.com really is yourbank.com when you use the HTTPS address. When you use an HTTP address, no certificate is used, so you really don’t have any way of ensuring that you’re not using a fake copy of a web site.

So how does your browser know that yourbank.com’s certificate is legitimate? Well, it’ a fairly complex system, and it’s not 100% perfect 100% of the time, but the short answer is that there are 3rd-parties that certify SSL certificates. And your web browser is configured to use those third parties to double-check the identity of the HTTPS addresses that you visit.

What Isn’t HTTPS?

Ok, so now we know that HTTPS encrypts your communication with web servers and certifies web site owners. So now let’s talk about what it can’t do (despite what your friends tell you )

It doesn’t protect your computer from hackers and viruses

Remember, HTTPS doesn’t have anything to do with protecting your physical computer. It’s all about protecting your web traffic and verifying web site owners. Protecting yourself from hackers and viruses is a big subject, but here are a few solid recommendations:

• If you are asked to patch your computer or web browser, do it as quickly as you can. If you have the option of patching automatically, then do it. Also, don’t forget that you need to regularly patch Flash and Java.
• Use an anti-virus
• Use a hardware-based firewall. Most consumer-grade wireless access points (aka routers) have one of these built-in.
• Supervise your children when they use a computer
• Use a web browser plugin like Web of Trust (WOT) to help you identify potentially-hazardous web sites.

“But wait” you say. “Won’t using HTTPS help keep my Facebook account from being hacked?”. Yes, it definitely will. What I’m talking about now is protecting your physical computer from bad people, not your web site accounts.

It doesn’t protect your content once it’s on a web site

Ok, here’s a hypothetical. Let’s say that you write a very sincere, emotional and (most of all) private message to one of your friends using Facebook (or any other messaging account). A few days later, you learn that a bunch of Facebook servers have been hacked, and you worry that someone else might publish your super-personal message for all of the world to see. But you have nothing to worry about, right? HTTPS encrypts all of that stuff, so the bad guys can’t read it, right?

Well, you would be half right. HTTPS does encrypt your web communication, but it doesn’t encrypt the data once it’s on the web site. That level of security is handled by the web site administrators, and it varies from great to awful. Please note that most web sites do nothing to encrypt your content once it’s on their site. Also, please note that most web sites also do a pretty crappy job of protecting their servers from hackers.

So if this is a concern, what can you do? If you want to store personal information on a web site, one thing you can do is insist that the site administrators encrypt the content on the server. If they don’t, then find another web site that will listen to you. Dropbox.com encrypts the content on their servers, and it’s reason #47 that they’re so awesome

In the end, the best defense it to think twice before posting something online.

When Should I Use HTTPS?

You certainly don’t need to use HTTPS with every web site, and most sites still don’t support it. So when should you use it?

Required

You simply should not use one of the following web sites unless they support HTTPS.

• Banking And Finance Sites Including PayPal
  • If your bank makes you do anything involving your password or you personal account information without HTTPS, then get a new bank.
• Anything involving your credit card
  • It always surprises me when I see a reputable online shopping site that doesn’t use HTTPS on the page where I enter my credit card information. When I see this, I either use a competitor who does use HTTPS or call the retailer to make my order.

Recommended

• Email and Facebook Passwords
  • It’s a very good idea to use HTTPS with any email or social networking site, especially if you like to use that site in a public place using a shared WIFI connection. It protects you from having people steal your passwords and your cookies.
  • It’s important to secure your email and social network accounts because some of them can be used to obtain bank passwords. Also, people may try to use these accounts to scam money out of your friends and family.
• Online Storage Sites
• Any site where you exchange personal information

How Do I Know If I’m Using HTTPS?

This is a complex and delicate question, so I will need to defer to the experts. Here’s how you can determine if you are using HTTPS properly in all of the major browsers:

• Internet Explorer (see “How can I tell if I have a secure conneciton?”)
• Firefox
• Chrome

Facebook Hacking Threat Revisited

Ok, so let’s revisit the statement that I started this article with:

“Facebook isn’t using HTTPS by default any more, so your PC might get HACKED!”

Ok, so knowing what we do now, what’s the risk?

1. The communication between your web browser and Facebook won’t be encrypted, so anyone could steal things like your password and cookies (which can be used to spoof your identity).

2. You can’t be sure that Facebook.com is really Facebook.com because the site isn’t using a certificate. Someone could therefore trick you into using a fake version of the web site.

Why are these risks? In either case, someone could use your Facebook account to scam your friends and distribute malware. And if you use Facebook as your primary e-mail account (which you can do now), then they may be able to obtain passwords for web site accounts that are tied to your credit card or bank accounts.

Conclusion

Ok, so I hope this helped de-mystify HTTPS a bit. Good luck staying safe and remember that it pays to be at least a little paranoid about sharing information online.

Posted from Diigo. The rest of my favorite links are here.

• The Perils of Premature Optimization | Good Math, Bad Math
  • This is an awesome explanation of why you shouldn’t change things in a system unless you have the data to back it up.
• TorqueBox: TorqueBox Slides From JUDCon:2011 Boston
  • Hooray for TorqueBox 1.0! I really can’t wait to play around with this project myself.
• The April 21 Amazon Disruption: Wrapping Up | Engine Yard Ruby on Rails Blog
• Amazon — The Purpose of Pain
• Shady Illuminations
  • These are three links related to the EC2 outage. Long story short, you should avoid putting your entire system into EC2 (or any single data center for that matter). They’re good reads for people see no disadvantages to cloud computing.
• Career 2.0: Take control of Your Life – Surya Suravarapu’s Blog
• Career 2.0 Preso Video
  • The Career 2.0 video is a really great place to start if you’re a technologist who is worried about his or her career.
• The “book” is dead [dive into mark]
  • “The book is dead. Long live content.”
• Google Voice VoIP on Android just got a lot easier with PBXes peering | Kyle Hasegawa
  • This is a pretty old blog post, but I’m looking for a good way to do SIP on my new Android phone, and this looks like the most promising process so far.

Posted from Diigo. The rest of my favorite links are here.