Bacula-users

Re: [Bacula-users] Is Bacula and a LTO drive right for me?

2015-05-17 10:24:22
Subject: Re: [Bacula-users] Is Bacula and a LTO drive right for me?
From: Ana Emília M. Arruda <emiliaarruda AT gmail DOT com>
To: Florian Rist <frist AT fs.tum DOT de>
Date: Sun, 17 May 2015 11:21:47 -0300
Hello Florian,

On Sun, May 17, 2015 at 6:48 AM, Florian Rist <frist AT fs.tum DOT de> wrote:
Hi Ana​,
thanks for your reply.

​You're welcome :-)​

 

> ​The most recent tape drives technology are LTO-6. The LTO-6 tapes
> have a native capacity of 2.5 TB and up to 6.25 TB of compressed data.
> Unfortunately it is really difficult to reach such amount of data in a
> tape. Maybe a 1.5:1 compression rate depending on your data.

Compression rate will be not good here, as most of the data is image and
video data, usually already well compressed.

​So you will need a lot of space for your full backups.


> So you will need more than one tape for a full backup and this will
> need
> manual intervention for changing tapes.

Yes, I know, as long as this is supported (and as far as I can see it
is) by Bracula that's fin. I remember it was difficult using Amanda in
1996 or so.

> If this is not a problem for you Bacula and an LTO drive is a
> feasible solution. Otherwise you should probably think about a tape
> library for this work.

Yes, a library would be good, but I cant afford one now. Maybe I could
get a old used library and replace the drive by a new one...

> ​Yes, You can have full/differential/incremental backups in a
> ​hard disk and then write once a week to tape. This is commonly
> known as disk-to-disk-to-tape (D2D2T) backups.

OK, in this case how much hard drive storage would I need? Enough to
hold the full backup ore just a few TB for the weekly incremental
backups?

> ​What do you mean about "slow Network"? Could you be more specific?

100Mb/s and not the best topology, a few PC via VPN through 100 MBit/s
LAN
​​
​I don't think this will be a problem. I had this topology a few years ago with a standalone LTO drive. And it worked fine for a few GB being backed up in a few nightly hours.​
 

> Are your data go across wan links?​ There are lots of known cases
> with Bacula working across wan links with no problems.

No WAN, I just wondered if I need to ensure a minimum data throughout
for the LTO. I member some problems in this respect with the DDS drive.

​I think you should do a few questions about your data.

1) How important is my data?
2) For how long should I keep a backup of them? When they will be reclaimed? I need to keep them just for a total disaster recover​? They could be reclaimed from a year ago? From a week ago? From a month ago?

​There are a lot of Bacula can do for you, but it is important to have this previous knowledge about your data.

It is clear that you will need a full backup​ of about 18 TB.  But will you need 1 full backup per month? 1 full backup per week?

A simple solution could be having one full backup per month and daily differential. In this case, you will need to keep 2 full backups and about 30 daily differential.

Your full backups could be divided into smaller ones to fill in one tape. And you could run daily differential and full backups from different data. This way you could use a low cost storage array and your tape drive (which is your technology?).

Please, could you tell us what are your needs about backup retentions and periodicity? I'm sure you will have a lot of people here to help you.
 


See you
Flo


​Best regards,
Ana​

 
------------------------------------------------------------------------------
One dashboard for servers and applications across Physical-Virtual-Cloud
Widest out-of-the-box monitoring support with 50+ applications
Performance metrics, stats and reports that give you Actionable Insights
Deep dive visibility with transaction tracing using APM Insight.
http://ad.doubleclick.net/ddm/clk/290420510;117567292;y
_______________________________________________
Bacula-users mailing list
Bacula-users AT lists.sourceforge DOT net
https://lists.sourceforge.net/lists/listinfo/bacula-users

------------------------------------------------------------------------------
One dashboard for servers and applications across Physical-Virtual-Cloud 
Widest out-of-the-box monitoring support with 50+ applications
Performance metrics, stats and reports that give you Actionable Insights
Deep dive visibility with transaction tracing using APM Insight.
http://ad.doubleclick.net/ddm/clk/290420510;117567292;y
_______________________________________________
Bacula-users mailing list
Bacula-users AT lists.sourceforge DOT net
https://lists.sourceforge.net/lists/listinfo/bacula-users