Hi all, this is primarily aimed at those here who have UPS (uninterruptable power supply) battery backup units. I seem to recall Kirk has one, and maybe others here do as well. We have a power outage here every 3-4 months, lasting anywhere from one second to close to 3 hours so far. So, I had been thinking of getting a UPS some day for a while now. According to my server/router's uptime, our most recent outage happened 36 days ago, and it lasted for a second, if not less. Everything including clock radios and stove clock seems to have survived it, except for the server. The fans and drive stayed on, but the machine was unresponsive, forcing me to power cycle it. That's when I decided that this happens frequently enough, and is annoying enough to maybe turn some day into in the near future. Until I researched UPS units, my idea of how they work was perhaps too idealistic. Power fails. Server properly shuts down. Power comes back on, server starts up. I found out though that this doesn't seem to be exactly how things go though. My server is setup in bios to turn on whenever power is applied. My research seems to indicate that there are two extremes as far as UPS units go. In the first extreme, power fails, the server shuts down. However, since the UPS isn't fully drained, the power from the UPS stays on, and the server doesn't start back up when the power company gets their act together, and utility power comes back on. That's fine if someone is around to press the power button. However, what if when this happens everyone here happens to be on a longer vacation? In the second extreme, some UPS units are set to cut power, and reapply power again about a minute after utility power comes back on. If the server shuts down before utility power comes back on, that's good. If utility power comes back on before the server shuts down, then the UPS causes the very problem it is supposed to prevent. This leads me to conclude that they're worth getting if one has a backup generator, or power outages tend to be short, and the UPS unit doesn't cycle the power. I also question the value of a proper shut down these days. Before journaling file systems, an improper shut down was a headache. Now though, it doesn't seem to be such a big deal. I've been through power failures maybe ten times now, and every time so far, the journals were recovered, and the system fully booted up, and was ready for prime time without my intervention (except in cases of split second outages). On the other hand, when we were having some electrical work done recently, I asked the electrician to wait for me to shut down the server before he cut the power, instead of just letting him cut power whenever he was ready. To keep this somewhat on topic, since the server only has USB ports, and no serial port, I was concerned about the compatibility of USB UPS units with gnu/linux. Based on reviews, the unit I would get if I decide to get it seems to be compatible with gnu/linux using USB to communicate: http://www.newegg.com/Product/Product.aspx?Item=N82E16842101311 Finally, though not strictly necessary, I can't help thinking that it would be nice to power my dsl modem, network switch, wifi access point, server, and maybe charge other battery devices during a power outage for a while. I'm also wondering how hard it is to find replacement batteries locally or on-line? While I see UPS battery backup units on newegg, I haven't yet found a category with replacement batteries for them. The reviews seem to indicate that new batteries run for about $30 U.S., so that isn't bad, if I only knew I'd be able to find them in order to buy them. So for those of you who have these units, are they worth it, or are they maybe less valuable to have than in the past? Thanks for any comments. Greg -- web site: http://www.gregn..net gpg public key: http://www.gregn..net/pubkey.asc skype: gregn1 (authorization required, add me to your contacts list first) -- Free domains: http://www.eu.org/ or mail dns-manager at EU.org
