Adventist Health CTO McGovern remembers working with mainframes 20 years ago, when critical data was backed up to tape. Two copies had to be made of everything, because some tapes turned out to be unreadable, and the nightly backup process would tie up the mainframe for as long as seven hours, he said.

"The Internet storage model is more reliable, more cost-effective and more assured than anything we've done in the past," McGovern said.

Using in-house resources to maintain data gives a feeling of safety and quick availability, but that may be just an illusion, he said. A tape stored in a leaky company warehouse may be less retrievable than data stored in a third-party cloud. Either way, the IT department should go through regular drills to make sure archived data is usable, McGovern said.

Internal storage, one of the most proprietary areas of IT, still has its own costs and pitfalls, said Nucleus Research analyst Rebecca Wettemann.

"If all my data is in a proprietary storage architecture within my own architecture ... is it less difficult to get it out and move it to another vendor? The answer is probably no," Wettemann said. The costs are likely to be higher, too, because a company may have large investments in specialized training as well as hardware and software, she said.