Just don't learn at the expense of others. A badly configured
server
can cause collateral damage, both in increasing SPAM and blacklisting
innocent users that have IP addreses 'near' yours.
Agreed. Personally, to me the best way to learn if you want, is to set up
your internal network as an intranet. For instance, I have
mydomain.com
which is now hosted and independent of all my junk at home. Here at home, I
have mydomain.intra. What I do in here affects no one but me and my (ever
patient) wife. To be honest, even with our five computers I don't even
bother running anything much other than Samba, so that we can keep our stuff
on a RAID, as my wife has some horrible curse with failing disks. Even name
resolution I just set up host files, because with the 4 systems I would want
to access by name it is not worth setting up DDNS.... But you can set up
your own internal DNS server, use Dynamic DNS, secure pop, secure smtp,
Samba, and anything else you want, and not run the risk of bothering anyone
else on the internet, or invoking the wrath of your ISP.
With a couple of machines, Fedora, and VMware Server and/or Xen you can set
up two domains in your house firewall them behind iptables firewall with
virtual networks, send mail back and forth between them, learn to lock them
down, and everything else under the sun... You can make a mess fast and
make no one want to slam their head against a desk but you. You can also
download Solaris 10, FreeBSD, and Novell Netware (they have a 5 User
unlimited time Demo out there somewhere on their site), Windows Server 90
day licenses and so on and really keep yourself busy. Set up NFS, RIS and
Software Distribution Servers, Samba servers for Windows Clients; your
options, and ability to learn, are virtually limitless with a couple
computers these days... and really if you can learn to hop on any *nix or
windows/whatever system, and have a good fundamental knowledge of networks,
you only make yourself more valuable. It won't teach you everything there
is to know about a corporate network, but it will get you on your way...
beside being able to sit in front of a Novell, Windows, Linux, BSD, Solaris,
or Mac system, and feeling comfortable is a good feeling.