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IPtables, SVN, and NMAP

I reviewed some material on IPtables, SVN, and NMAP just for the sake of keeping my mind busy. Here are some useful notes:

  1. IPtables - best resource found at HERE
  2. SVN - best, as in the quickest and simplest intro could be found HERE
  3. NMAP - I honestly don't see in using it for more than port-scanning in a few instances. Anyway, here are a few other options that might come in handy at some point.
nmap -sT/sS/sX/sF/...[-P0] IPADDRESS(range) == to check which ports are open
nmap -sP IPADDRESS(range) == a simple ping scan for availability
nmap -sO IPADDRESS(range) == check what IP protocols are available
nmap -sV IPADDRESS(range) == a scan with version detection
Other useful flags:
-O
== detects OS, part of -v (verbosity) flag as well
-A == detects OS and versions
-v == request high verbosity/detail
-F == performs a fast scan of only a few common ports

Installing Perl modules

Perl modules may be installed using the CPAN module or from source.
SOURCE

From CPAN

perl -MCPAN -e shell (to get an interactive CPAN shell)
perl -MCPAN -e 'install Time::JulianDay' (if you know the name of the module, you can install it directly without interacting with the CPAN shell)

Typing just perl -MCPAN -e 'install PerlMol', I managed to install the PerlMol module from scratch.

Manual installation

1. Download the Perl module from CPAN or other site.
2. Extract the tarball.
3. Run perl Makefile.PL
4. Run make
5. Run make test
6. Run make install

Checking for existence of a Perl module

perl -e 'use module' checks if the module is installed.

For example, I checked if I have the Trig module by typing this prompt:
perl -e 'use Math::Trig'

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