Linux – KeepAliveD Documentation

You could use something like Kickstart, which is a feature of the anaconda installer of Fedora, CentOS, RHEL, and derived distributions that lets you completely customize an installation to your liking. You can choose which packages you want to install, the partition layout, network configuration, package repositories, root password, and much more. You can also create pre and post-installation scripts that do whatever else you might want. You can run the install fully automated, or pick and choose what you'd like it to prompt for. All settings are defined in one simple (not XML) text file, which you can make by hand or with the graphical system-config-kickstart tool.

Once you've got that put together, you can roll your own custom CD if you like, or set a network location in your kickstart file, which can be a local or Internet mirror, via FTP, HTTP, or NFS. Your kickstart file can also be on the network, so you can just burn one stub install disc to bootstrap the installation (or use vanilla install media) and have it use as many different configurations as you can stand. You can even network boot it, eliminating removable media altogether.

The network options or custom spun media eliminate you from needing the "huge package repository", yet it will still be there if you decide you want to add something. But, if you want to go whole hog, you can build your own repository, cherry-picking RPMS from upstream, customizing SRPMS to your liking, rolling your own, or even hacking a make && make install or tar -jxf into the post-install script.

Many distributions have similar functionality, some of which also understand Kickstart files even if they don't implement their entire feature set (like Debian).

This really is two questions, and should have been split up. But since the answers are relatively simple, I will put them here. These answers are for GNU grep specifically.

a) egrep is the same as grep -E. Both indicate that "Extended Regular Expressions" should be used instead of grep's default Regular Expressions. grep requires the backslashes for plain Regular Expressions.

From the man page:

Basic vs Extended Regular Expressions

In basic regular expressions the meta-characters ?, +, {, |, (, and ) lose their special meaning; instead use the backslashed versions \?, \+, \{, \|, \(, and \).

See the man page for additional details about historical conventions and portability.

b) Use egrep '(.)\1{N}' and replace N with the number of characters you wish to replace minus one (since the dot matches the first one). So if you want to match a character repeated four times, use egrep '(.)\1{3}'.