Thursday, February 01, 2007

Making Samba your Primary Domain Controller - Part Deux

As promised, here is the continuation of my post on making Samba your Primary Domain Controller. Before you actually begin the installation, it's a good idea to try and work out some of the gritty details. How many users will there be? What operating system should you use? For example, if you have several hundred potential users, putting everything on that dusty old Pentium II with a single 10BaseT card in it is probably not such a great idea -- particularly if it's your phone that rings when network problems crop up.

Hardware Recommendations
Hardware requirements, as always, depend on the load to be handled. Since this is our single point of entry into network services, if the PDC goes down, then users can't access the network. This is bad. However, if you are going to have a relatively small number of users, re-purposing older gear might be a viable option for you. If this is the case for you, then you might want to keep a few rules of thumb in mind:

  • Processor: A pair of Celerons or Durons will hold up better under load than a single Pentium class processor. If you have an old 2 way (or 4 way, or whatever) machine kicking around, give it a hard look. It might be a viable candidate for this.
  • Memory: Processor speed is only one factor to bear in mind; memory is equally important. Max out your RAM.
  • Disk: The disk subsystem also plays a major role. Samba acts as a file server. File servers read from and write to the disk, and they do it a lot. Get the fastest drive you can afford. You won't regret it.
  • Network interface card: do you have an old 10 Base T card in there? Get rid of it, and spend a few bucks on at least a 100BaseT card. You won't regret it at all.
Operating System requirements
Samba runs on just about anything, including your toaster. It's supported on Linux, Unix, BSD, Mac OSX, Netware, AmigaDOS... well, you get the idea. This is largely a matter of taste. I've always been a fan of BSDs, so I chose FreeBSD. For fun, I did a simultaneous installation on CentOS as well.

First check to see if you have it installed already. Note these innocuous words of wisdom directly from the Samba site (emphasis added):
As always with Linux, there are two ways to install an application: RPM, or compile from source. (OK, there are three: Debian's apt-get. As I don't speak Debian, I'll leave that to the Debian Linux gurus.) RPM is easier, compile from source gives more control. Whichever method you choose, be sure to remove any existing Samba installations first.
Please, make certain you do not have Samba installed. If you do, remove it. If you happen to be running some version of Linux (an RPM based distro such as RedHat, CentOS, etc.) you can check by executing this command as root:
rpm -qa | grep amba
Yes, I left the "S" off, and no, that's not a typo. Sometimes it's installed as Samba-XX.rpm, and sometimes as samba-xx.rpm.

Which Version?
Samba 3.0 adds native connectivity with Microsoft's Active Directory, support for Microsoft's version of Kerberos, SAM (Security Accounts Manager) replication, and lots of other nifty features. It's the way to go. Older versions also support PDC functionality, but hey, that's yesterday's news. The latest version is faster, more stable, and more functional. It's a no brainer.

Next time, I'll take you through the actual installation and smb.conf configuration.