We are going through an RFP process of changing hosting companies for most of our servers (~10 fairly powerful workhorses and database servers).
When the existing company was picked I wasn't at the company, nor have I worked with hosting companies in the past (Always had hardware on site in previous companies). We will be doing site tours for each of the companies over the next few weeks. What type of things do you normally look for? Questions to ask their on site staff, etc? Anything that can help me evaluate and compare.
Most of the of the hosting companies maintiane VM Ware farms with DR sites connected via fiber.
Best Answer
It's a good thing that you're thinking about what questions to ask your hosting company, but I think you're approaching it backwards. First figure out your requirements, and then ask each company how their infrastructure will meet them.
When they're explaining how their infrastructure meets your needs don't be afraid to ask questions, and if you aren't satisfied with the answers you're getting don't be afraid to insist on having someone relatively upper-level give you a good explanation -- You are giving the hosting company good money, and if their sales guy can't explain things to your satisfaction insist on a network engineer or someone from their Datacenter Operations team to explain things.
In addition to what everyone else has mentioned, some other things to consider (geared toward colocation - hosting your hardware at someone else's facility):
General
(NO plastic zip ties, NO tape)
(They may say no. If they say yes stick your head down there and look around. Again, all cabling should be neat and bundled with velcro ties. Suspended cable trays are important here to allow airflow. See cooling.)
Network
Power
Cooling
(If they lose an air conditioner will the room stay at temperature?)
(Assuming they use a traditional down-flow cooling system that bows cold air into the floor, stand at a perforated tile near an air conditioner, then at one as far from the AC unit as you can get -- The breeze should be relatively even)
(air-side economizers, heat wheels, etc?)
Security and Access
Monitoring
(they might say no, but if it's a really slick system they might want to show off)
Managed Services (If you want them)
Disaster recovery
I put this last because it's really a minimal concern -- Datacenters spend money making themselves very reliable and robust in the face of subsystem/component failures. Disaster Recovery in the sense of "what happens if my datacenter goes away" is best addressed by having another datacenter, so the questions I ask are along those lines: