We have a huge world wide support structure in place. 24x7 customer support including on-call technical support teams. We also have a huge number of Systems Engineers in the field to go onsite for harware issues and Regional Tech Support people that go onsite to address issues with software.
If a customer is down, we move like lightning and do whatever is necessary to get them up and running at any hour of day or night. This includes shipping replacement systems immediately anywhere in the world they are needed.
This requires a large number of people to keep this type of suport going...and the customers love it. Or so they tell me. It's just that IT spending is at a standstill, mostly. We're still number 1.