How to speed up the booting process for Grub2 boot loader using profiling

When you boot up your machine Grub does a search for all the necessary drivers to load. This takes time. Instead of making Grub search for these drivers, the profiling actually makes Grub remember every driver necessary to work, thereby cutting down all of the driver load times.

Profiling is a way of indexing IDes required for Grub during its part of the boot process. This allows it to locate required files quicker in the subsequent boots and thus accelerate the boot process.


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GNOME Gconf Registry Cleaner - Gconf Cleaner

GConf is a system of storing preferences of most of the installed applications, as well as the environment and desktop for GNOME for Linux, It is intended for user preferences; not configuration of something like Apache, or arbitrary data storage.

GConf involves a few new concepts, but no rocket science. Essentially GConf provides a preferences database, which is like a simple filesystem. The filesystem contains keys organized into a hierarchy. Each key is either a directory containing more keys, or has a value. For example, the key /apps/metacity/general/titlebar_font contains an integer value giving the size of the titlebar font for the Metacity window manager.

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Speed up Internet access by using Persistent DNS caching with Pdns - Ubuntu Linux

pdnsd is a proxy DNS server with permanent caching (the cache contents are written to hard disk on exit) that is designed to cope with unreachable or down DNS servers (for example in dial-in networking).

pdns installation:
Open up the terminal Application > Accessories > Terminal and type following command:

sudo apt-get install pdnsd

Once installed the software is configured via the file /etc/pdnsd.conf.

The next thing to do is to edit the pdnsd configuration file /etc/pdnsd.conf to specify which DNS servers the cache should use for its own lookups.

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How to Limit network access by user / group using iptables - Owner Match

Iptables and netfilter is a Linux kernel 2.4+ iptables administration tool. netfilter and iptables provide a Linux kernel framework for stateful and stateless packet filtering, network and port addresss translation, and other IP packet manipulation. The framework is the successor to ipchains.iptables is built on top of netfilter, the packet alteration framework for Linux 2.4.x and 2.6.x. It is a major rewrite of its predecessor ipchains, and is used to control packet filtering, Network Address Translation (masquerading, portforwarding, transparent proxying), and special effects such as packet mangling.

Owner match:
The owner match extension is used to match packets based on the identity of the process that created them. The owner can be specified as the process ID either of the user who issued the command in question, that of the group, the process, the session, or that of the command itself. The owner match only works within the OUTPUT chain, for obvious reasons: This module attempts to match various characteristics of the packet creator, for locally-generated packets. It is only valid in the OUTPUT chain, and even this some packets (such as ICMP ping responses) may have no owner, and hence never match.

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