Friday, March 30, 2012

A Backup Arrangement with Beyond Compare

I had been using Beyond Compare (BC) for a year or two.  Over that period, I had settled into what seemed like a decent backup arrangement.  This post describes that arrangement.

For a while, I had a spare internal partition to which I would make backups.  The original concept there was that I would use rsync or some other program to make backups on an hourly basis.  That setup had fallen into disrepair, mostly because I didn't quite like how it was working.  So I didn't have an hourly backup at this point.  The arrangement described here is more on the longer-term (e.g., daily, weekly, monthly) level.

My backup took place on external drives.  I had an external enclosure that I would have to open up (removing several screws) to swap drives, and I also had an inexpensive dock that I could just plug an internal SATA drive into.  Both seemed to work equally well.  The enclosure was handy for unplugging the drive and taking it with me.  Now and then -- especially when the tornado alarms sounded -- I visualized myself grabbing it and running for the basement.  I wondered if that would be one of those fateful delays that would cost me my life.

The external enclosure had an eSATA connector, but my previous motherboard had not been able to accommodate eSATA on a hot-swappable basis.  In other words, I had to reboot in order to get the system to recognize it.  It also had a USB connector.  The external dock (i.e., not the enclosure) was also a USB device.  USB was slower but very adaptable.  That was almost always what I used.  Some partitions on the external drive were compressed, to save space.  I had the impression that this did not help with the USB connection -- that the CPU would unpack the file before shipping it across the slow USB cable to the computer, resulting in at least as much data moving along the wire -- but I hadn't verified that.

For my purposes, Beyond Compare offered two key concepts.  First was the workspace.  If I plugged in the external drive that I used for daily backups, then I would open up the DAILY workspace in BC.  If I plugged in a drive that I used for weekly backups, then I would choose the WEEKLY workspace.  I also had a SIMPLE COMPARE workspace that I would use for random tasks -- say, comparing two folders on a one-shot basis.  And I had a NETBOOK workspace that I would use to synchronize my laptop.  GoodSync might have been better for that if I had been using the laptop frequently, but at this point it was mostly a case of keeping the data on the laptop current with the desktop.  That is, I was mostly doing one-way updates, from desktop to laptop.

My workspaces differed in the tabs they made available.  In the DAILY workspace, I had a tab for each day of the week, plus whatever other comparisons I would want BC to make on a daily basis.  Likewise for the WEEKLY and the other workspaces.  In other words, I used a workspace as a place where I would be able to see tabs for each comparison that I wanted BC to make, whenever I plugged in the weekly drive or the laptop or whatever.

I found that the best approach was to start BC first, let the workspace load, and only then turn on or connect the external USB drive.  That way, BC would not try to do complete comparisons for all of the open tabs.  It would do its calculations for the relevant folders on the drives inside the computer, which were already available to it, but on the external drive it would have to wait until I gave it the go-ahead within a particular tab.

Focusing on the DAILY workspace, I was writing these notes on a Friday.  So to guide my remarks, I opened BC at this point.  Somehow, I had arranged for the DAILY workspace to come up by default; or maybe BC just defaulted to the last open workspace.  I wasn't sure how I had arranged that.  When BC was up and running, I turned on the USB drive.  It took that drive a moment to become available.  (I found that AntiRun was useful, not only for protecting my system from autorun malware and such, but also for telling me when a drive really was online or offline, and for giving me a functional way of taking external drives offline.)

I went to the Friday tab.  BC had stalled because the Friday folder on the external drive had been unavailable.  I told it to retry; and now that the USB drive was connected, BC ran its comparison.  (Details on the kinds of comparisons available, and other program capabilities, are available at Beyond Compare's website.  Their forums and other tech support had been very responsive, the few times I had contacted them.)

I had modified my BC toolbar to present the red Mirror button.  This said, basically, just overwrite whatever is in the backup space (in this case, the Friday folder on the USB drive) with whatever is on drive D in the computer.  Drive D was the one that I backed up daily.  So in this case, a number of files had changed since the previous Friday.  Sometimes I would take a look at them; sometimes not.  Usually not.  It seemed pretty rare that a file would be accidentally deleted.  Daily examination of all changing files had seemed to be overkill.

When I say that I would take a look, I mean that BC showed me two panes, one for each of the folders being compared.  To keep things organized, the left-hand pane was almost always the authoritative one.  The left-hand pane would correspond, that is, to a partition inside the computer.  So I was looking at the right-hand pane, corresponding to the backup device.  If I saw a file listed in the right-hand pane, but not in the left-hand pane, that would mean that it was on the system when I made my backup a week ago, but now it was no longer on the system.  BC would also alert me, with a red font, if the file in the right-hand pane was newer.  Generally speaking, that wasn't supposed to happen.

I had an alternating weekly folder on this backup drive.  I used that one on Saturdays.  That's the one I examined more closely.  If I found that something was missing on Saturday, and I didn't think it should be missing, I could then click on the tabs for the other days of the week until I found the last backed-up version, and I could restore it from there.

Drive D contained the things that were in more active use.  I also had a separate partition, drive E, for things that took up a lot of space and didn't change very often.  Videos were the main example.  Because there were so few changes there, it was easier to look at the differences identified in BC, and verify that additions and deletions were desired.

In net terms, I liked this arrangement because it gave me some flexibility to combine automated and manual processes.  I wasn't vulnerable to one of those black-box backup solutions that would seem like they were working just fine until the moment of crisis, when I would painfully discover that I had failed to adjust some essential setting, or that the drive was malfunctioning, or whatever.

In this arrangement, if I was worried that files were missing, I could look down through lists of what was being added and deleted.  If I was confident that everything was fine, I could just click the Mirror button and the backup would happen.  I could also combine both approaches within a single tab, by telling BC to mirror only the selected folder(s).  This would gradually reduce the number of things remaining on the screen (assuming I had BC set, as usual, to Show Differences rather than Show All).  When confronted with what looked like a mess, I could thus eliminate the parts that seemed OK, and focus on the files and folders that didn't seem like they should have been getting added or deleted.

Like most other computer-related matters, my backup approach continued to evolve.  But as I say, I had been using BC for a while, at this point, and I was pretty much satisfied with the combination outlined here.