Redundancy

[William R Vogel]

To start, I'm not bashing anyone with this, just passing on something I learned the hard way.

I've been running Xtension since it was supplied on floppy disk and would run on a 68000. ;) As the system expanded I became more dependent on it.

Then I had a catastrophic HDD failure on the PPC Mac that I was running at the time. It took me a while to recover and caused serious inconvenience during that time.

Coming from a telecom background, I remembered that all common equipment in a switch had backups, and inter-office trunks also had spares. Since Xtension had become something I depend on, I took a lesson from my telecom experience.

Some background: I've always run Xtension on dedicated Mac. This means that I'm fine with a 4-5 year old Mac for the job. (I often use the older Mini when I upgrade my desktop.) I can get a second, used, Mini for a reasonable price. I use a KVM and USB switch for the monitor, keyboard, and CM-11. Both Minis are connected to my LAN and can be accessed with screen sharing.

On a monthly basis I power up the backup mini in Target disk mode and copy the Xtension database to same. (Kinda stumbled on that one when the database moved to the Documents folder.) Otherwise I keep the backup Mini powered down to protect it from power issues.

Besides protecting me from hardware failures, this setup allows me to upgrade the primary system and let it run for a while before copying to the backup. So if there is a serious issue, I can just switch to the backup Mini, which still has the old software and database.

I hope this might be helpful.