Just had my first run-in with a program called netcat, which I understand is known as the “TCP/IP Swiss Army Knife” (I’m intrigued).

I was trying to set up an easy way to ssh to a box that’s hiding behind another “gateway” box. I’ve gotten used to this method:

$ ssh -t gateway ssh user@desthost

That method ssh’es to my “gateway” box and then executes another ssh command from there to the final destination, desthost. Nice that it’s a one liner, but still a little tedious to type.

I was going to write a shell script to contain that command, in order to save myself some time, but I decided to first look at ways to do it with the ssh config file in ~/.ssh/config.

Sure enough, I stumbled across a method using the ProxyCommand option for ssh.

So, heres my new entry in ~/.ssh/config:

Host desthost
	User root
	HostName desthost
	ProxyCommand ssh erikm@gateway nc %h %p 2> /dev/null

So what happens here is on the gateway server a program called “nc” is executed — that’s Netcat. Netcat allows you to direct TCP/IP traffic to a different destination, in this case “desthost”. I could even direct it to a different port, but in this case it stays on port 22.

So my local ssh client ends up making login request to root@desthost by way of erikm@gateway.

The resulting behavior is exactly as if I were ssh’ing to a host that’s on the same network I am.

And the beautiful part is that scp and sftp uses this config as well, so if I do:

scp desthost:~/somefile.txt ./

it’s going to copy that file over the connection that’s specified in the config.

Just learned a super handy tidbit about SSH. If you’re in a remote session and you need to step back to your local computer, do this:

1. Hit ‘Enter’ to make sure you’re on a new line
2. Type ~
3. Hit ‘Ctrl+z’

This will stop your SSH process and bring you back to your original session. To get back to your SSH session, type “fg”, the normal command to bring a process back to the foreground.

Courtesy of this article on serverwatch.com. I recommend reading the article to learn more tricks with the SSH client.

Getting better using the uber powerful ‘find’ command…

find . -name ".svn*" -exec sudo chown -R $USER '{}' \;

Changed ownership of all .svn directories in a project. Got the command right on the first try.

I’ve been using the Awesome window manager on my netbook since I got it a few months ago (Jenny calls it my “booknook”).

Awesome is a lightweight tiling window manager that works very well on a low-power netbook. It doesn’t take up my screen real-estate, nor does it require very much CPU power. A collection of handy keyboard shortcuts allows you to have a very useful desktop environment in a small space.

Recently, one of the default keybindings stopped working for me. Specifically, it was Mod4 + ‘w’. This is the command to show the menu, which can also be shown by clicking on the right mouse button. Mod4 is the windows logo key on your keyboard.

I discovered that the show() function for the menu object has changed in the arguments it takes, so an older config file isn’t going to be compatible with newer versions of Awesome.

To fix Mod4 + w on your system, find the line in your rc.lua that has:

awful.key({ modkey, }, "w", function () mymainmenu:show(true) end),


Change it to:


awful.key({ modkey, }, "w", function () mymainmenu:show({keygrabber=true}) end),


I was able to find this change to the default rc.lua here:

http://www.mail-archive.com/awesome-devel@naquadah.org/msg04889.html