Home Computing
Computers
At present I own the following computers:
Currently in use
- An Intel i5-2500 quad-core desktop with 20 GB of memory, DVD,
external SATA and USB 3.0 connections.
There are three disks; a 250GB SSD as system disk, a 500GB Western Digital
magnetic disk, and a second 250GB SSD which is used entirely used for
Virtualbox images. The home directory on the system SSD is mirrored
onto the 500GB disk every night by a cron job.
There is also an external disk
caddy connected by a USB 3.0 cable with a second 500 GB disk.
There is a single monitor, a 24 inch Asus with 1920*1080 resolution.
- A Lenovo Thinkcenter, with 8GB of memory and a 250GB SSD. There
is also, on the shelf, a 500GB disk with a validly-licensed
copy of Windows 7. I only use it once a year to update
my Garmin GPS unit for the car. I can't find any other uses
for Windows 7. My wife Louise uses this machine for email, web
browsing and on-line shopping.
- An ancient Toshiba Satellite; a 32-bit machine with 3 GB of usable memory.
I put in a 100 GB SSD, and installed Peppermint Linux, which is a distribution
suited for low-power machines. It works well as a spare machine that I can
use for giving the occasional presentation. The battery is totally dead, so
it needs mains power whenever it is in use. I also installed a wireless mouse,
as the trackpad is unusable, to me at any rate. Since the machine cost
me a few beers from a friend, it is great value.
- A Samsung Tab2 tablet, which gets a great deal of use.
- An Asus Chromebook, intended as an alternative to the tablet when
a keyboard was needed. It has proved useful for Zoom meetings, but
not a whole lot else so far. It was not a very successful purchase - there
is not really a use case for it. However, it seems sturdy and reliable,
and I will look for new uses for it.
No longer in use and in most cases gone the the great computer morgue in the sky
- A Pentium 4 1.8 MHz, with 512Mb of memory and an 80 GB disk.
It has a DVD writer, a 10/100
Ethernet card, and a hardware modem that I have never used.
I have recently equipped both this machine and the next one
with hard disk caddies, making it much easier to use different
disks with different operating systems. I strongly prefer this
approach over multi-boot systems, as there is no risk of damaging
more than one OS at a time.
I currently have disks with Ubuntu Hardy Heron, which I use as my "production" system, a Windows 2000 disk,
and a copy of FreeBSD 6.3. There are also several other older IDE disks, with all sorts
of old stuff on them - such as a bootable copy of Caldera Unix for a 486, from
before the time of the famous SCO lawsuit.
- A Pentium 120 that I have had since 1997, with 128 MB of
memory and two 10 GB disks. It too has a disk caddy, and I have an almost-never-used
Windows 95 configuration for it on a 1.7 GB disk. It also has a CD-RW
writer, a hardware modem and an Ethernet card. The CPU
fan failed some time ago, and I didn't notice. So it now
reports its speed as 100 MHz; it has presumably got a little
old and tired. But it has been extremely reliable for the
whole of its life. In fact, I upgraded it from a 486 in 1997,
so the power supply has been running since 1993, almost
continuously. (The power supply looks pretty dusty, and I have cleaned out the vents
to some extent, but I expect it will fail before very long.)
It has now been taken out of service, and sits lonely and unused in the basement.
For a while I used it as a web server, using Apache. One minor innovation
is a CGI script, in Perl, which generates a set of index pages
for my collection of digital photographs. With this, I have
only to save a new photograph in the appropriate directory,
and it will appear automatically in the index page for
that collection.
- A 486DX-33, with 20 MB of memory, and a 500 MB disk.
It ran an early version of Linux (Caldera 2.0 from memory), and
had an Ethernet card and a modem. I got this machine
from my sister-in-law, who said it was completely dead,
and so she would not accept any money for it. She was
quite right - it was as dead as a doornail, with a failed
power supply. A used replacement later, and it was up and running
Windows 3.1, to my pleasant surprise. I later installed
Linux; a version by Caldera, I am sorry to report. It ran without
interruption for over three years, until the power outage that
disrupted life in Ottawa in August 2003. It has been running off and on
since then, and never crashes. It was taken out of service when we
moved house in 2006, but still sits in my basement ready for use in an 'emergency'.
(What kind of emergency would need a 486 I can no longer imagine).
- An Asus Eee 701 netbook, which I bought in March 2008. It has a wireless
connection, and I used it in other parts of the house, and in hotel
rooms when we were traveling. It runs a customized version of Linux, and
is very compact and portable. The battery life is very short,
and it has a serious problem with screen flickering, so it must be
counted as deceased.
It has effectively been replaced by tablets; first a Nexus 10, and now
a Samsung SM T318.
Networking
The i5 and the Thinkcenter are networked together, using Ethernet
and a wireless router, which isolates my home
network from the outside world. The high-speed connection
from our local cable service comes in to the
router, which provides Network Address Translation, and
gives me some confidence that hackers will have a relatively
hard time. I could improve the protection with a little
more work - one of the many things on my "to-do" list.
Getting the networking to do what I want has been more
challenging than I expected. It proved quite easy to get
to the stage where I could "ping" each machine from the
other, but I had a learning curve to climb before I was able
to share directories across the network using NFS, and to be
able to telnet and ftp between them. It all came down to
getting the configuration files right, and now I know how
to do it, it seems easy.
I run Samba, which enables a FreeBSD or Linux
machine to "pretend" to be an Windows NT server, so that
it can serve files to Windows clients. This enables me to access
my Linux home directory from a Windows machine - even from a
Windows machine running under VirtualBox.
Backing up
As it is now
I have three spare 500 GB disks that can be mounted in a USB
socket, and I do a full backup every night at 3:00 am. I rotate
the disks every month, and keep the most recent one hidden away.
I also copy everything of value to the Amazon S3 service, which
provides very inexpensive storage that is 'off-site'. This backup
is done once each week.
I have copies of very critical files, such as the Amazon S3 keys,
ssh keys and passwords, all encrypted, in several places, including
a USB memory stick that stays with me at all times.
As it was years ago
Now everything is set up the way I want, and seems to work very
reliably. I use the Pentium 4 as a backup machine,
and the home directories from the other machines are backed up
automatically each night. Every month, I copy the contents
of these backups to a CD or DVD, so I have a reliable record of all
useful files that were on each machine, using a recording
medium that cannot be affected by power surges or other electrical
failures. I keep backup copies of the most critical CDs at
an "off-site location" - that is, not in my home. Any files
which are not in the home directory, and which I have modified,
are copied to a place in the home directory structure just before
the backup is made. This includes the many configuration files
such as those in /etc. My method here is simple. I include
a comment with my initials in any file I modify, and these
are picked up automatically by the backup script, using grep.
I am thus quite confident that I can reconstruct the state of
a machine in an hour or two, even if its filesystems are
completely destroyed. And yes - I have practiced this.
I also have several flash memory drives, that connect to a USB
port. These are excellent value for money, and are getting
cheaper by the month. I bought a 128MB flash drive for $29 from Staples,
and reformatted it as a UFS device, and it is used for an
additional nightly backup of selected files from my home directory.
I have another which lives on my keychain, and holds encrypted
backups of a handful of files that I consider most valuable. These drives are
now getting so cheap that I may replace it with an 8GB drive which will hold
everything I value, including photos (but not movies).
IOmega ZIP drive
I owned one of the early Iomega Zip drives (the 100MB version) for several years,
and with help from a FreeBSD committer was one of the first people to use
one with FreeBSD. Despite the frequent "click of death" problems, mine
functioned perfectly for several years, with never a dropped byte. I recently
moved it from the Pentium 120 to the Pentium 1.8 GHz, and it lasted a week
or two before dying of "click of death". So it may, as rumoured, have something
to do with the power supply characteristics. It is not worth replacing, and I
have long ago copied anything of value to CDs. So - ZIP-RIP!
Last updated : 2020-07-09