My kingdom for a reliable server OS

After wasting what became a fortnight with Xandros Server I took the sensible decision to throw the thing back at the company and demand a refund. I eventually got most of my money back though for some reason they thought they were entitled to keep the shipping charge they made – even though its product doesn’t work! Bad product = Bad company.

Ditching Xandros left me back at square one – servers still running Win2k3 and no Exchange replacement.

My intention in using Xandros had been simple enough – replace the email server OS and application with a non-MS alternative – while retaining Exchange compatibility so that all my PIM data cold be held centrally – and in a way that allowed synchronisation with my PDA and phone.

Behind that simple requirement, of course, lies a morass of complexity. For a commercial grade network, the most important task performed by a Windows server is domain control – the central management and control of access to all network resources. Only after this basic requirement is met can you go on to provide network file shares, web and email services etc. In the Windows networking scheme, one (and only one) server acts as the Primary Domain Controller (PDC) holding the master copy of all login IDs and security authorities. One or more other servers can act as backup controllers (BDC) answering login and access requests by automatically synchronising their copy of the security database with the PDC. Since Windows Server 2000, this basic mechanism with its poor mix of MS proprietary (eg; WINS) and open services (eg; DNS) has been supplanted by Active Directory (AD) – still MS proprietary but easier to manage and automatically updating DNS etc. My Win2k3 domain was AD based.

In part, Xandros failure to live up to its promises is down to the fact that it uses the well-known and well-established Samba software to provide Windows-style domain services. None of which is a criticism of Samba, which is one of the best established, most reliable and useful Open Source projects around, backed up by people who really know their stuff and are very happy to support their “product”.

Simply put, Samba does not (at the time of this writing) support or understand Windows Active Directory – it only supports the older PDC/BDC mechanisms. More than this, interoperability between Samba domain controller services and their Windows equivalents is severely limited – you can’t, for example, have a Samba PDC with Windows based BDC – or vice-versa. For my simple needs, these restrictions would not be a problem – but they do mean that planning the migration from Windows to Linux server technology required a little thought. And again, for my relatively simple needs (and, I suspect, the needs of most small to medium sized businesses) the lack of AD support would not be an issue, especially as it’s not that hard to have a Linux DHCP service update a DNS domain automatically so that XP (and soon-to-be) Vista based PCs wouldn’t have to bother with the creaky old MS WINS directory service to find each other.