However, remember that unless the website server and MS SQL server machines are in the same datacenter, there will be some performance issues.
How is he accessing the SQL Server data? If it's from ASP script (often the case) you'll find that ASP on Linux is not the same as "proper" ASP on Windows!
Realistically, I think your customer is going to want an all-Windows solution (hosting on Windows 2000). The only other option is to convert the database to MySQL and the scripts to PHP, but you're talking a lot of work!
Chris at TDMWeb.com
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