Directory indexing

Directory indexing feature improves file access time in large directories or directories containing many files by using hashed binary trees to store the directory information. It is a good way to enable it for example on a web server which has thousands of files in a single directory:

tune2fs -O dir_index /dev/sda3

Directory index will be created for new files but you can regenerate index with:

e2fsck -D -f /dev/sda3

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Adding new splash image to grub

All you need to do is to copy splash image file to /boot/grub/ directory and edit the grub menu configuration file at /boot/grub/menu.lst and add a line

splashimage=(hd0,5)/boot/grub/splash.xpm.gz

Remember to change the (hd0,5) param for your configuration, this line shows the grub loader where it can find the image on the physical disk. Because the partitions has not yet mounted we must give the physical address by saying the bootloader the hd0 and partition number 5. You can learn your linux partition number by looking at the similar line

title Ubuntu, kernel 2.6.12-9-386
root (hd0,5)

in your grub config.

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SSH login without password

If you want to use passwordless ssh login feature, you should use public key authentication mechanism. To do this, remote server must be configured to enable public key authentication (enabled by default) and you should have an ssh public/private key and store your public key at the remote side's special file: ~remote-user/.ssh/authorized_keys

Remote server setup: Check the following lines exists and uncommented in the /etc/ssh/sshd_config, if not you must add it and restart ssh server at the remote side:

RSAAuthentication yes
PubkeyAuthentication yes

Local setup: You must generate an public/private key pair for your own if it's not generated before:

ssh-keygen -t rsa

You can select defaults just hitting enter a few times. After that your public key will be in the ~/.ssh/id_rsa.pub file, you must add this file content's to ~remote-user/.ssh/authorized_keys file. You can scp to copy id_rsa.pub at the remote side and after that you can append id_rsa.pub contents into authorized_keys file at the remote side.

This is a trivial process and there is a special script utility which basically makes this copy and append task called ssh-copy-id:

ssh-copy-id remote-user@remote-host

Now, you can login without entering password

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gnormalize - audio converter, encoder, ripper, meta data (tag) editor and audio cd player

gnormalize is a front-end to wavegain, an audio converter, encoder, ripper, meta data (tag) editor and audio cd player.

Supported formats: MP3, MP4 (or M4A or ACC), MPC (or MPP or MP+), OGG, APE and FLAC. gnormalize decodes the MP3, MP4, MPC (or MPP - MusePack), APE (Monkey's Audio), FLAC and Vorbis OGG files to wave, then normalizes the wave to a targeted volume level and re-encodes it. gnormalize can also rip audio cd; encode audio data; convert audio format between MP3, MP4, MPC, APE, FLAC and OGG; and change the encoding and ID3 tag properties of final normalized files.

Key Features:

* Convert from/to MP3, MP4, MPC, APE, OGG, FLAC and Wave;
* Support for LAME, FAAC, OGGENC, MPPENC, FLAC and MAC encoders;
* Support for LAME, FAAD, OGGDEC, MPPDEC, FLAC and MAC decoders;
* Rip audio CDs utilizing cdparanoia or cdda2wav;
* Play audio CDs utilizing cdcd or Audio::CD or gnormalize::cdplay;
* Edit and get Meta data like artist, title, album, ... ;
* Support normalization with adjustable sensibility;
* Can normalize/convert files recursively into the directory;
* Normalize with ReplayGain algorithms;
* Includes wavegain to normalize wave files;
* Read the CDDB entry for an audio CD with CDDB_get;
* Translation to English and Portuguese (Brasil).

Download : Here

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How To Increase SSH Connection timeout

Do you get annoyed when you have a SSH session open, visit your browser for a while, and then return only to find you were disconnected? So, to avoid this ...

Open /etc/ssh/ssh_config on your (client) computer. Add the following line:

ServerAliveInterval 180

Just remember this -- if you leave SSH open accidentally, anyone else can get on it. Remember to close your session when finished.

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