It seems as though nearly all web hosting providers promise 99% uptime. Therefore, the promise alone does not make the choice any easier. While there are sites that provide monitoring services that rate the actual uptime of hosts, the real question you should ask a web host is what the guarantee entails.
There is no question that even the best web host will have some down time. That is why no host promises 100% uptime. When your server does go down, what are the consequences? Will the web host say nothing and just eventually turn it back on, pretending like nothing happened? Will they apologize after a reboot? Will they assure you that it will never happen again?
The truth is, when a website is critical to an organization or business, a web host, which is also a business, should compensate the customer for downtime. That guarantee should include a clause about compensation. It may take the form of pro-rating a monthly fee or some other form, but the ultimate outcome should satisfy the customer.
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