I understand your question now. Well, you can’t. Or you can stop going on vacation and never disconnect. But who wants that?
The most important thing is to be in a market that can handle a bit of downtime. Pretty much every service out there has had some down time so don’t think your business is toast if you go down for a bit on a vey occasional basis or if you take a couple of days to answer a question.
If you build your service correctly it should not go down regularly. It will go down, but not regularly. So most of the time you’ll be fine.
Sleep: I used to have my monitoring system wake me up. After a few too many false positives, and with the system growing more stable after a couple of years I just sleep.
Vacation: There is internet pretty much everywhere now. Take your laptop with you obviously. I have T-mobile’s plan (in the US) that works in most countries. With today’s smartphones you can answer questions from that device quite readily. If you get a notification that something really is broken, you can head back to your hotel and pull the laptop out and get to work. I think I’ve only done this once, where I debugged something from a high-speed train over an intermittent 3g connection. You make do.
[grandpa voice] When I started I had a dumb-phone and could hardly get away from my computer for fear that I was missing a notification email. Getting a Blackberry Curve was the most liberating experience. [/grandpa]
Offline: This one is a tough one. I love camping in the wilderness, but it was hard to do because I was always worried something would happen to my service and I wouldn’t know about it. Here again the increasing stability of the system and my trust and understanding of it is what allowed me to eventually disconnect for three days without worrying too much.
Here are a couple extra things I learned:
- never release a new version less than 2 weeks before vacation/disconnect. (duh)
- do a “health check” before going on vacation or camping. Anything that has an upper limit (hard drive space, DB ids, whatever) should be checked against their current use and trend.