The hosting server's operating system. As you know, and if you don't, you just found out, beside Microsoft Windows there are others operating systems, like Mac OS, Linux, Sun's Solaris, etc. The most popular choices for hosting servers are: Linux/Unix with Apache as web server and Windows and its IIS service (Internet Information Server). Some say that Linux is the server of choice due to greater stability and security; others say that Windows is catching up on Linux. We are not here to get in a Linux-Windows fight.
1. Understand the differing types of hosts: shared, collocated, unmanaged dedicated, and managed dedicated.
2. Go for stability, not just size. Research how long the hosting business has been in operation. See if they have recently changed ownership, and if they show positive cash flow.
3. The possession of fully redundant data centers. If you are considering doing business with a smaller hosting vendor, ensure that they have adequate power and connectivity capabilities. Inquire as to the number of lines the facility has. Do they possess an on-site generator? Does the generator receive regular checks and maintenance? What is the average utilization of the connections available?
4. How skilled is their staff? When you need customer service of a technical nature, you need it immediately, right? Find out the availability of their systems administrators.
5. Other customer's reviews of the hosting services. Same as any business, the hosting vendor should be able to provide good references.
6. Is the potential host flexible? In the future, your needs may change. Can you upgrade services should the need arise?
7. Make sure that the host does not have blackholed IPs. The host that you want to do business with would not be one that promotes porn sites, spammers, or other security issues. You are considering associating your business with this host. Think about it.
8. Begin with and maintain a clear and written understanding of all services and all charges for them.