20090506

APC Serial Ports, and websites, wikis, and backups, oh my!

How many of you use APC brand UPS gear? Raise your hands! Ok, you can put your hands down.

Now, how many of you have connected the UPS serial port to your computer, to get power information, or to have the UPS tell your computer to shut down? Not so many? How many tried, but had trouble? 

Question 1: Were you using the APC-supplied cable (with the correct end plugged into the UPS)?

I ask, because the APC serial ports are unusual! If you use one of the cables you have lying around your shop, there is a good chance that the UPS shut down, and would not turn on again until you disconnected the cable. 

When I first tried this, the cable was missing, and I tried various cables in the shop (because I didn't have passive signal tracers at the time). Nothing worked, and I sometimes lost power. 

When I had another UPS, with the APC cable, I found that the cable wasn't long enough, and some of the cables I tried using to extend the run caused troubles. That's when I dug deeper into the problem. Here's what I've found;
  • The APC port puts data and ground on unusual pins!
  • The UPS uses the two outputs and inputs for other purposes!
You can actually make a "Big Red Switch" for your small APC, using a couple wires and the DE-9 connection. Because of the signals being on unusual pins, when you plug in a PC with a non-APC cable, you are actually applying a "shut-down" hard-wired signal to the UPS.

I made an APC Clues web page, documenting the findings, in late 2007. But, for some reason, I guess I didn't post it. Only when I needed the information again (and couldn't find it) did the panic set in, because some of the legacy information is no longer on the web.

That brings us to....

Question 2: How many of you are making backups of your critical files?

You can replace the word "critical" with Photos, Homework, Research, Family Tree, Tax Info, you get the idea. The data that you do not want to lose in a hard disk crash, or on a lost Flash Memory Drive. Where do you keep it, and how often do you update it?

I use an automated system, backing up critical files to a disk "in the cloud", for $99 a year. This runs every time I start up my computer, and I put a lot of faith in it. But, I need to pay money to keep it alive.
I also make manual copies to a 1 GB external hard disk (but I have to remember to move new files). I should really set this up to run automatically.
For some of my hobbies, and console stuff, I put copies of the web. (Technically, I made them for display on the web, so I guess the copies on my home machine are my backups.)
For some data sets (photos for some of my hobbies or family, or my console-related files, for example) will be occasionally copied to a CD or a DVD, and distributed to friends, family, or colleagues. While it isn't complete, this may be one of my best backup methods!

My point here is that disks die, memory sticks get lost, laptops get stolen, and even servers or hosting companies die without prior notice. Data stored on websites may still be transient. If it is your data, you should make multiple, diverse copies, and make more copies over time as new media becomes popular. (And, if the data is sensitive, ENCRYPT IT!)

When I couldn't find my APC web page (I was certain that I had made one), I started checking the Wacky Wayback Machine to try to find the information. Sometimes this comes up empty, if the domain/pages you seek were not deemed interesting enough.

In closing, if you have any APC UPS gear, please check out my APC Clues page. Save a printed copy, because you may want that information again someday.  ;)

    Regards,

       -Z-

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