"; */ ?>

linux


22
Aug 10

Gitolite: Does Not Appear to be a Git Repository

Have a user, whose public key was successfully added under “gitolite-admin/keydir” and whose rights were successfully configured under “gitolite-admin/conf/gitolite.conf”.

When this very user is cloning an existing, correctly configured repository, his/her identity ( public key ) is not being passed correclty => hence notice a password prompt:

$ git clone git@yourgitserver.com:your-project
Cloning into your-project...
git@yourgitserver.com's password: 
fatal: 'your=project' does not appear to be a git repository
fatal: The remote end hung up unexpectedly

Here is the way to help out git / gitolite to understand which identity ( key ) to use:

$ vi ~/.ssh/config
host gitolite
     user git
     hostname yourgitserver.com
     identityfile ~/.ssh/mypubkey

Now changing “git@yourgitserver.com” to “gitolite” does the trick:

$ git clone gitolite:your-project
Cloning into your-project...
remote: Counting objects: 83, done.
remote: Compressing objects: 100% (77/77), done.
remote: Total 83 (delta 3), reused 0 (delta 0)
Receiving objects: 100% (83/83), 156.45 KiB | 49 KiB/s, done.
Resolving deltas: 100% (3/3), done.

Notice, public key was successfully accepted => hence there was no password prompt, and the clone was successful.


21
Aug 10

Making Git to Add Empty Directories

Since git is a “content” based SCM, and empty directories by git are not considered to be content [ which is arguable ], the only way to add them is to add “.gitignore” to every empty directory.

That may sound like a weird task after each time you create a Grails / Rails / Spring Roo / … project, since there are going to be many empty directories right from start.

To ease the pain, here is an alias you can add to your “.bashrc” to use before “git add .”:

# add '.gitignore' to all the empty dirs
alias ged='for i in $(find . -type d -regex ``./[^.].*'' -empty); do touch $i"/.gitignore"; done;'

one liner author: justinfrench.com


20
Aug 10

Connect to Wireless Network at Startup

Assuming WPA/WPA2 security is used, first thing to do is to get a hash/hex of the password. Below “myssid” is the wireless network’s SSID, and “mypassword” is the password for this network.

Step 1 Generate a WPA password hash to be used later when setting up network interfaces:

$ wpa_passphrase myssid
# reading passphrase from stdin
mypassword
network={
	ssid="myssid"
	#psk="mypassword"
	psk=2f0568b3492812bd56b946dbaf3fd7dd669b9a4602a09aa6462ff057949b025c
}

Step 2 Configure a wireless network interface using the password hash from Step 1:

$ vi /etc/network/interfaces
   auto wlan0
 
   # configuring a static IP
 
   iface wlan0 inet static
   address 192.168.0.34
   gateway 192.168.0.1
   network  192.168.0.0
   broadcast 192.168.0.255
   netmask 255.255.255.0
 
   #  OR if static IP is not needed ignore above 6 lines and uncomment the one below
   #  iface wlan0 inet dhcp   
 
   # configure WPA/WPA2 security
   wpa-ssid myssid
   wpa-psk 2f0568b3492812bd56b946dbaf3fd7dd669b9a4602a09aa6462ff057949b025c

9
Aug 10

Website Root “index.php” is not Executed

If mythtv and apache server are installed on the same box, beware of the evil trick:
mythtv is going to modify “/etc/apache2/sites-enabled/000-default” and inject it with “DirectoryIndex mythweb” after each ‘VirtualHost’:

<VirtualHost *:80>
    DirectoryIndex mythweb
        ServerName site.com
        ... ... ...

their (mythtv’s) DirectoryIndex does not have “index.php” as one of the entries, that means that the root of the website will not display, and instead an “Index Of” and directory listing will be displayed.

Removing “DirectoryIndex mythweb” fixes the problem (or you can edit mythweb’s directory index, that works too):

<VirtualHost *:80>
    #DirectoryIndex mythweb
        ServerName site.com
        ... ... ...

22
Mar 09

VNC Into Remote Server Without Typing a Password

vnc without typing a password

I have a simple setup where one of my Ubuntu boxes is hooked up to the old Mitsubishi 50” TV via s-video. The box is hidden behind the TV, and is, of course, online. It has Mythbuntu installed, and functions as a full blown multi media center.

Besides all other goodies that are installed on the box, I recently installed rtGui (A web based front-end for rTorrent) on it. Hence anywhere I go, I can connect to it over the web, and throw a torrent link that will start the download right away – convenient. ( here is how to “install rtGui on Ubuntu” )

Currently, I control my media box the most straightforward way – from my laptop. There are many other options available: Gyration Remote (In-air cursor control using Patented Gyroscopic Motion-Sensing technology – 2.4GHz RF technology for up to 100 ft), mini wireless keyboard, and many others, but I don’t mind a semi-manual way to control the box by using my laptop. There is one little problem though – every time I am VNCing to the box, I have to enter a password – not convenient…

First thing I tried to find a “no typing password” solution was:

$ vncviewer remotehost.com -p dummypasswd
VNC server supports protocol version 3.8 (viewer 3.3)
Cannot read valid password from file "dummypasswd"

Here I just wanted to see what the error message would pop up, to get more clues on where to look. Now I’ve got the clue: “there should be a valid password file”. Next thing to do is to read about “vncviewer”:

$ man vncviewer
 
       -passwd passwd-file
              File from which to get the password (as generated by the vncpasswd(1) program).

Excellent – now it is official, just need to use “vncpasswd”:

$ vncpasswd
The program 'vncpasswd' can be found in the following packages:
 * tightvncserver
 * vnc4-common
Try: sudo apt-get install
<selected package>
bash: vncpasswd: command not found

Seems like its not installed, which is an easy problem to solve…

Step 1. Install “tightvncserver”.

$ sudo apt-get install tightvncserver

Check that “vncpasswd” is installed:

$ vnc [TAB][TAB]
vncconnect  vncpasswd   vncserver   vncviewer

Step 2. Create a vnc password file with “vncpassword”.

$ vncpasswd
Using password file /home/user/.vnc/passwd
VNC directory /home/user/.vnc does not exist, creating.
Password: [TYPE YOUR VNC PASSWORD HERE]
Verify: [TYPE YOUR VNC PASSWORD HERE]
Would you like to enter a view-only password (y/n)? n

Step 3. VNC into the remote system without typing the password.

$ vncviewer remotehost.com -p /home/user/.vnc/passwd

As you see the only thing I need to provide now is the password file – no need to type the password every time I need to watch a movie. And to make it even more convenient, I can now create a launcher that will launch “vncviewer remotehost.com -p /home/user/.vnc/passwd” on a simple mouse click:

media center launcher

Want to do something else simple and convenient? Try to “run commands remotely via SSH with no password“.

VNC away!