I agree with Mr. Gardner on this as well.
Something else to consider though is that 22.5MB is the total you
have now, but when you do incrementals onto the same media, that
total can get much higher depending on the data that changes.
For example, I have a user that edits photo's that are between 200MB
and 900MB in size. If I backup the 900MB file on Monday night, she
changes it on Tuesday, Retrospect will then back it up again on
Tuesday night. And no, it does not erase the previous version. I've
had users that upgraded their systems (Win98 to Win2k recently) that
when Retrospect goes out there to back it up, the whole thing looks
new.
Just a warning. I've learned to deal with it, but me having to "deal
with it" vs just letting it go is just a matter of having more backup
capacity.
I'd recommend getting at least double of what you really need, but
bigger is better.
I used to backup 40 Macs over LocalTalk. It took 2 weeks of nightly
backup to complete a single Level 0 (L0=Full/new backup) backup on
all systems. We then went to 10BaseT (hub) and it cut it down to 3
days for L0. We then went to 10/100 switches where about 1/3 of the
machines were 100Mbit and the rest still at 10Mbit and it cut the
time down to about 1 night + 1 hour. Our backups run from 6pm to
6am, so that would be 13 hours.
Now we have a mostly 100Mbit network, but the number of machines
being backed up has grown to 120. It takes about 14 hours still, but
there is a lot more data out there now.
A bit of history...when I was backing up over LocalTalk, the largest
hard disk we had in any Mac was 500MB. Now 500MB won't even hold
most of the System Folders! Largest single drive right now in our
Macs is 50GB I believe.
We have two backup systems. One is Windows NT running Retrospect and
using a DLT autoloader. The other is a Mac with a DLT 20/40 on it
backing up 11 machines, all of them are on switched 100BaseT.
>on 11/17/00 4:51 AM, Rich Grenyer at [EMAIL PROTECTED] wrote:
>
>> I've got to implement overnight backups for 31 Macs, 5 iBooks and 3
>> PCs, across a 10MBit LAN on a weekly basis (approximately 22.5 GB
>> storage transferred a night) What am I going to need in the way of
>> server capabilities (I'd like a Mac for security reasons), and will
>> thin ethernet carry this sort of transfer reliably? Does anyone have
>> a recommendation for the sort of storage device for this much stuff?
>
>Ethernet will carry the transfer reliably. At optimal speeds, it would take
>about seven hours to back up 22.5Gb over a 10Mbit line, and that does not
>include Retrospect's preparation and comparison routines. A more reasonable
>timespan would probably be more like 15-20 hours, depending on your hardware
>and overall network utilization.
--
----------------------------------------------------------
To subscribe: [EMAIL PROTECTED]
To unsubscribe: [EMAIL PROTECTED]
Archives: <http://list.working-dogs.com/lists/retro-talk/>
For urgent issues, please contact Dantz technical support directly at
[EMAIL PROTECTED] or 925.253.3050.
