Hi

I am exploring various solutions for reliable backup for my exclusively
Linux populated LAN (3 machines).

What would provide me with the best value for money combination when the
important considerations for me (barring cost) are :

1. Speed of backup. (I do not want to spend hours backing up a few ten
GB's).
2. Number of cycles of backup (durability).
3. Total volume that can be backed up.
4. Portability.

?
I need a solution that can backup upto 30 GB or so. What is better ? Tapes
or external USB harddisks ?

Thanks.

On 2004-09-11, Madhusudan Singh <spammers-go-here@spam.invalid> wrote:
> What would provide me with the best value for money combination when the
> important considerations for me (barring cost) are :
> 1. Speed of backup.
> 2. Number of cycles of backup (durability).
> 3. Total volume that can be backed up.
> 4. Portability.

Tapes are still the best solution (IMHO) when the total volume doesn't
surpass the capacity of a single tape, an Exabyte (as someone else
suggested) can easily backup up to 100 Gb with a transfert rate of
30 Gb per hour, tapes are reusable and the MTBF is greater than
disks.

Davide

--
Pohl's law:
Nothing is so good that somebody, somewhere, will not hate it.

Davide Bianchi wrote:

> On 2004-09-11, Madhusudan Singh <spammers-go-here@spam.invalid> wrote:
>> What would provide me with the best value for money combination when the
>> important considerations for me (barring cost) are :
>> 1. Speed of backup.
>> 2. Number of cycles of backup (durability).
>> 3. Total volume that can be backed up.
>> 4. Portability.
>
> Tapes are still the best solution (IMHO) when the total volume doesn't
> surpass the capacity of a single tape, an Exabyte (as someone else
> suggested) can easily backup up to 100 Gb with a transfert rate of
> 30 Gb per hour, tapes are reusable and the MTBF is greater than
> disks.
>
> Davide
>

How much would a 100 GB Exabyte drive with tape cost ? If it is too
expensive, then it might not be right for me.

On 2004-09-11, Madhusudan Singh <spammers-go-here@spam.invalid> wrote:
> How much would a 100 GB Exabyte drive with tape cost ?

You'd better ask to a dealer or retailer for that. If it doesn't matter,
you can even found the drive used on e-bay. Tapes is a different matter,
since you want more than one (usually) and they need to be replaced at
least once a year, even if I run backups on the same tape for over
3 year without problems. But in the end, you make backups for security,
so it's better to switch the tapes every now and then.

When my company replaced the old Mammooth-2 tape with a tape library
(8 tapes, automatic change mechanism, 800Gb minimum capacity) we spent
a good 6000 euro worth of equipement.

Davide

--
Very few profundities can be expressed in less than 80 characters.

Madhusudan Singh <spammers-go-here@spam.invalid> wrote in message news:<ejs0d.25$r41.886@news.itd.umich.edu>...
> Hi
>
> I am exploring various solutions for reliable backup for my exclusively
> Linux populated LAN (3 machines).


Try an AIT tape drive - they are available as external scsi if you
want - and will hold 100GB with a supposed write time of 24GB per
minute

DAT drives are cheaper, but typically hold one tenth of the capacity
and go at one tenth of the speed.

There is something to be said for using disks instead of tape, but the
number of generations you can keep is limited, whereas you can keep
buying blank tapes. If you just want the latest snapshot, then disks
may be worth considering. A bit of a cron job can save images
unattended, provided you have solved the problem of backing up any
databases.

you mentioned portability - there is no need to move the backup
device, you can access it over the network from the other machines.

Robert E A Harvey wrote:
> Madhusudan Singh <spammers-go-here@spam.invalid> wrote in message news:<ejs0d.25$r41.886@news.itd.umich.edu>...
>
>>Hi
>>
>> I am exploring various solutions for reliable backup for my exclusively
>>Linux populated LAN (3 machines).
>
>
>
> Try an AIT tape drive - they are available as external scsi if you
> want - and will hold 100GB with a supposed write time of 24GB per
> minute

24GB per minute??? No way. That would be 400MB/sec, or way faster than
any of today's hard drives, faster than any SCSI interface, faster even
than a 32-bit/33MHz PCI bus. The specs I've seen for AIT-3 show 24MB
(not GB) per second or just under 1.5GB per minute. (That's assuming
2:1 compression, too.)

http://www.storagebysony.com/product...ain.asp?id=170

John-Paul Stewart <jpstewart@binaryfoundry.ca> wrote
> 24GB per minute??? No way. ... The specs I've seen for AIT-3 show 24MB
> (not GB) per second or just under 1.5GB per minute.
quite right. That was a typo. I;ve been working nights!

Thanks to everyone who responded. I am afraid that my question might have
left some erroneous impressions ("barring price" was meant more as an
attempt to find the best technical solution after which I would find the
cheapest of the set of solutions suggested).

I administer a small home network and price is an important consideration
for me. So, solutions that run into more than a few hundred dollars are not
acceptable for me.

So, in light of that, what would be better ? An external USB hard drive, or
USB tape drives ? I am willing (after exposure to the prices) to have a few
hour long backup times as long as the backups are reliable and portable.

["Followup-To:" header set to comp.os.linux.misc.]
On 2004-09-12, Madhusudan Singh <spammers-go-here@spam.invalid> wrote:
> Thanks to everyone who responded. I am afraid that my question might have
> left some erroneous impressions ("barring price" was meant more as an
> attempt to find the best technical solution after which I would find the
> cheapest of the set of solutions suggested).
>
> I administer a small home network and price is an important consideration
> for me. So, solutions that run into more than a few hundred dollars are not
> acceptable for me.
>
> So, in light of that, what would be better ? An external USB hard drive, or
> USB tape drives ? I am willing (after exposure to the prices) to have a few
> hour long backup times as long as the backups are reliable and portable.

My solution was to buy a used DLT tape drive on eBay. I just got another
DLT-IV drive (20/40GB capacity) for about US$25. Tapes, often new, are
also available quite reasonably. Many companies are moving away from
their DLT-III and DLT-IV hardware and media because they need higher
capacity. This equipment is still quite rugged and very reasonably
priced on the used market.

You could probably put together a very decent DLT-based backup system for
about US$200, including tape drive, cables, SCSI adaptor, and sufficient
tapes for multiple backups.

--

-John (john@os2.dhs.org)

Thanks to everyone that responded. Driven by price, and by the knowledge
that things that are harder to do usually do not get done regularly, I have
purchased an Iomega HDD 80 GB with USB 2.0. Tape drives require manual
intervention while I could presumably just set up a cron job to
periodically back up stuff to the HD. It cost me $119 (buy.com) and thus
was far cheaper than even used decent tape hardware (I found no prices
lower than about $250).

Now I have a few questions :

1. To maximize speed of backup, which filesystem should I format the new HD
with (btw. how do I do it ?) ? ResierFS or ext2 or something else. I have
read that ReiserFS is better for large backups.

2. What would be a good tool to use ? Amanda or just a custom script that
backs up the stuff ? I have to backup two machines - one with 80 GB max HD
(actual usage is less than 40 GB) and another which is 40 GB max HD (actual
usage is less than 25 GB)