You should never have any doubt that your website is going to stay online at all times. No site, no matter how large, can possibly stay online all the time. With so many sources of interference, there will be times when the site will go offline, and it’s the responsibility of the host to make sure that it is quickly restored.
With some web hosts, this is a major concern. They have built their own back-up systems, but there are still a few who will run their own databases or other systems, which could cause problems for the site if it goes down.
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