Hello freeway people.
Having just gotton a zingy new iMac featuring Leopard, I have what may be regarded as a basic question.
I want to use ‘Time Machine’ as an option for backing up the contents of my 500gb hard disk.
I can never, ever foresee me using the entire 500gb volume with data (I take work off onto DVD monthly). So… do I need a 500gb external drive for my time machine back us… or would a 250gb or 320gb do?
I know it depends on the amount of work I have on the 500gb hard disk… but sometimes things are too obvious.
Sometime around 1/2/08 (at 13:55 -0500) David B said:
Having just gotton a zingy new iMac featuring Leopard
Congratulations!
I want to use ‘Time Machine’ as an option for backing up the
contents of my 500gb hard disk.
I can never, ever foresee me using the entire 500gb volume with data
(I take work off onto DVD monthly). So… do I need a 500gb
external drive for my time machine back us… or would a 250gb or
320gb do?
First of all, you should consider leaving work ON your hard disk as
well as archiving to DVD, at least until you do start needing more
room. Otherwise you’re just moving those eggs to an optical basket of
their own. And you may find you have read problems if you need to
pull something from a burned DVD a year down the line.
Second, your Time Machine backup will attempt to keep multiple
instances of the contents of your disk, backing up changes on an
hourly and daily basis. As your Time Machine storage runs low, the
oldest data is thrown away to make room for the new.
It is best to have a large drive for Time Machine so that it always
has room for an effective number of archive ‘instances’. Although
your process of removing work regularly will keep your requirements
down.
Time machine works by storing one big whopper of a backup, then
deltas from that. (It only backs up files that have changed since the
last time.) The real answer to your question is another question.
What do you want to use the backup for? If it’s just disaster
recovery, back to the last moment that you backed up, then you could
get by with a smaller disk (although they are getting cheaper all the
time). But if you want to take advantage of the promise of TM, and be
able to step back in time and grab something that you threw away, or
step back to a previous version from a few days ago, then I would get
something in the 500 to 1TB range. Disk is cheap. Data is infinitely
expensive.
Walter
On Feb 1, 2008, at 1:55 PM, David B wrote:
Hello freeway people.
Having just gotton a zingy new iMac featuring Leopard, I have what
may be regarded as a basic question.
I want to use ‘Time Machine’ as an option for backing up the
contents of my 500gb hard disk.
I can never, ever foresee me using the entire 500gb volume with
data (I take work off onto DVD monthly). So… do I need a 500gb
external drive for my time machine back us… or would a 250gb or
320gb do?
I know it depends on the amount of work I have on the 500gb hard
disk… but sometimes things are too obvious.
Yep, We used to back up to CD, and then DVD, some time back, until someone checked a DVD to see if it would read back. It wouldn’t. We can never again trust work/backup to go on CD or DVD. We don’t even buy them anymore.
Hard disc are cheap now, so put copies of data/or backup on at least two hard discs. This means you’ve got 3 copies of your work to go back to if disaster strikes. Oh, and ideally have the hard discs stored in different locations (not in the same building) to be on the ultra save side.
But saying that, TM looks an ideal method of backup/restoring stuff quickly.
On 1 Feb 2008, at 19:02, Keith Martin wrote:
And you may find you have read problems if you need to
pull something from a burned DVD a year down the line.
David Owen
Freeway Friendly Web hosting and Domains ::
Hard disc are cheap now, so put copies of data/or backup on at
least two hard discs. This means you’ve got 3 copies of your work
to go back to if disaster strikes. Oh, and ideally have the hard
discs stored in different locations (not in the same building) to
be on the ultra save side.
Folks thinking of doing this might like this: http://xrl.us/bfkk3
as it means you can read and write to a bare hard disk without an
enclosure.
Hi
Thanks for feedback all.
I shall invest in a large external drive. For this application does it make any difference if I acquire a USB2 or firewire connectable device?
This is our back up procedure at the moment for those interested:
Daily: work backed up to back up drive 1
Montly: one or two disks worth of work taken onto DVD and taken off macs
Monthly: duplicate files of work archived onto DVD placed onto back up drive 2
So work is effectively archived onto DVD and onto a back up drive. Back up drives 1 and 2 are ‘off site’ so to speak.
I want time machine to function as a safeguard whereby if something like the motherboard fries on my G5 (as did happen) I can plug the external drive (that time machine has backed up onto) and get going again pronto. I assume in this case, it’d be as simple as removing the entire contents onto the new mac
Sometime around 2/2/08 (at 08:25 -0500) David B said:
For this application does it make any difference if I acquire a USB2
or firewire connectable device?
FireWire is faster in practise. Yep, the 400mbit/sec of Firewire 400
is faster than USB 2.0’s 480mbit/sec. That’s because the data
transfer protocols are simply more efficient, and also less
susceptible to being slowed down by other devices on the same bus.
You’ll get much closer to Firewire’s theoretical maximum throughput
than you ever will with USB 2.0’s theoretical maximum.
Also, USB is processor-bound. Each bit has to travel through the CPU,
where FireWire is intelligent on its own. Each node can communicate
with each other node without involving the CPU in any part of the
discussion.
Walter
On Feb 2, 2008, at 1:42 PM, Keith Martin wrote:
Sometime around 2/2/08 (at 08:25 -0500) David B said:
For this application does it make any difference if I acquire a USB2
or firewire connectable device?
FireWire is faster in practise. Yep, the 400mbit/sec of Firewire 400
is faster than USB 2.0’s 480mbit/sec. That’s because the data
transfer protocols are simply more efficient, and also less
susceptible to being slowed down by other devices on the same bus.
You’ll get much closer to Firewire’s theoretical maximum throughput
than you ever will with USB 2.0’s theoretical maximum.
