ssh - authorized_keys (password-less login)

Gotta make sure the permissions are the following

[amitava@collab ~]$ ls -ld .ssh
drwxr-xr-x 2 amitava amitava 4096 Nov 9 12:27 .ssh

[amitava@collab ~]$ ls -l .ssh
total 8
-rwx------ 1 amitava amitava 611 Nov 9 12:26 authorized_keys

Linux command to report hardware architecture (i386, x86_64)

lshw

Anyone knows the darwin equivalent?

mini mac - can't eject cd while trying to install ubuntu

I was trying to install x86_64 version of ubuntu 9.04 server on my mini mac. However, mac mini can't handle x86_64 and needs i686. But now I can't eject the cd and I am stuck. After some googling I found out that you need to keep the option key pressed while booting up. This brought up a menu allowing me to boot off the hard-disk. Phew!

I found this today (07/20/09) - while booting up press the mouse button to eject the media from your CDROM drive

X11 port forwarding in macosx

I am running KVM virtual machines on ubuntu server host (on a mini mac). To gain access to the VM console from my macosx client, I use ssh X11 port forwarding like below

$ ssh -Y myhost

From within this ssh session, I run
$ xvncviewer

The Y option from man pages brings up the following:

-Y Enables trusted X11 forwarding. Trusted X11 forwardings are not subjected to the X11 SECURITY extension controls.

Batch compile elisp files in emacs

emacs -batch -f batch-byte-compile *.el

Mediawiki Blank Page

After installing Mediawiki successfully, I got a blank page. Please note that I am using CentOS5/Apache 2.2/PHP 5.1.2

I went to /etc/php.ini and changed "display_errors = On". This will allow php errors to show up. After this, I got the following error message

Fatal error: Class 'DOMDocument' not found in /var/www/html/wiki/includes/Preprocessor_DOM.php

So, DOMDocument is not enabled by default in CentOS PHP. I installed it as follows
sudo yum install -y php-xml

This did the trick.

Related Links
Mediawiki FAQ

How to get your current linux distro?

cat /etc/issue