Backup Medium Formats
Ignis at SourceForge
ignis is a special backup program for the SOHO sector. It implements a full-backup strategy, a mix between the backup schemes of GFS and Tower of Hanoi. It is meant for backing up onto DVDs or simular media. Normally, it is called via cron to perform the backups and checks. Reports are sent via mail. The ignis project is licensed under the GPL (v2 or later) !
If you have following scenario ignis is the backup solution for you:
ignis 0.5 released
ignis 0.4 released
New version of the homepage is online, which contains now some information on how to prepare the system for the using of packet writing for DVD-RW and DVD+RW.
ignis 0.3 released
start of this webpage.2006-08-12
ignis 0.2 released
Not all wanted features have been implemented so far,
specially the ones which are not 100% needed as e.g. the recovery can
be easily done without ignis tools with any system and standard open
source tools, like tar, gzip, bzip2 and gnupg. But these features are on the TODO list and hopefully this text
block can be changed soon.
The install is quite simple:
Q: Why the name ignis?
The backup schema is a mixture between GFS and Tower of Hanoi, which is optimized for the SOHO sector. It provides a cost effective backup solution with default only 15 mediums, but with which you get 180 week (~3.5 years) back, if you use it once a week. For the following discussion we talk about the default usage of 15 mediums:
This schema uses 3 classes (A, B, C) with each 5 mediums (A0-A4, B0-B4, C0-C4). Following rule defines which ID should be used next. All IDs from the class A need to be used before the next/first ID of class B can be used and all IDs from class B need to be used before the next/first ID from class C can be used. This simple rule leads to the following cycle:
A0 ... A4, B0, A0 ... A4, B1 ... B4, A0 ... A4, C0 ... B0 ... B4 ... C1 ... C4
Within the ignis releases you find a protocol that can be used for the full 180 runs cycle. (ignis_backup_protocoll-01.pdf)
A customer/friend comes to you for help. He owns a small company with 1 employee and both have their own PCs, but the data exchange is complicated and data security is no existent as both users are plain Office users with no idea how to do a backup. He has heard that an server could help, but he needs a really cheap and completely easy to use solution. He tells you after some questions that he has 500mb office documents and the same amount of emails and the amount should grow almost linear. (You of course checked that ;-) )
You go for a cheap shuttle barebone, which is small and silent (both very important for this area), with a DVD-RAM capable DVD writer (+ the other standard stuff, but no monitor or keyboard – use your own for installing). All together with 15 DVD-RAM mediums you get everything easily for under 600 Euro. You install Ubuntu server (5 years maintenance for free) with samba as file server with 2 shares (“data” is read/write and “snapshot” read only). As IMAP and SMTP server you use courier which comes also with sqwebmail as setup free webmail client. You specially use a maildir based IMAP server, which is faster and much better to backup. On the existing hardware router you forward the SSH and HTTPS ports to the server. After you did setup the standard virus/spam stuff (clamav, sanitizer, spamassassin) you install/configure fetchmail to get the mails from the various accounts they both have (and you wonder how they checked them regularly before). Next you configure/migrate the 2 clients to the new server and copy the office documents into the data share. Now your friend/customer is ready to work with the new system, and you have the time to build the snapshot and backup solution.
As first you install rsnapshot and configure it to make daily/weekly/monthly (on request even hourly) snapshots of the user directories (for the imap mailboxes and the private samba share), the data share and of course of /etc, /root, /usr/local. After this your friend/customer can restore an old version of a file just by going to the snapshot share and copy it back. As files in a rsnapshot snapshot have the same permissions/owner/group as the original files there is no problem with the user directories.
And now at last you are ready to install/configure ignis. You just setup one backup location, the “daily.0” directory of the rsnapshot snapshots with the directcopy method. This is only followed by labeling the DVD mediums with ignis and a marker stick, and the usage of both of their mail addresses for info and error mails and yours only for error mails.
Your friend/customer must now only exchange the DVDs according to the mails and/or the protocol list once a week. He is able to do the recovery on his own – he just needs to put the DVD into his Windows PC and copy the files he needs with the explorer and that up to 3,5 years back. After you told him that it is a good idea to place the DVDs at another location than the server you are clear to go.
All this gives your friend/customer a really cheap solution, which provides much more data security than the typical SOHO solution together with a great usability.
All DVD formats (DVD-RAM, DVD-RW and DVD+RW) and CD-RW are supported. It is important to note that burning onto DVD-RAM mediums does not work on my USB DVD burner, but works if i connect the DVD burner directly to the PC - so the usb bridge can not handle it. It is therefore recommend to test with one medium before buying all. With this commands you can fully erase the mediums:
# dvd+rw-format -force /dev/sr0
# dvd+rw-format -force=full /dev/sr0
I recommend the
use of DVD-RAM if it is possible. DVD-RAM is maybe not that well know as the
others so here are some facts:
So in short, for backups DVD-RAM mediums are the better format but support for the other two is also provided. For a closer look at the DVD-RAM read following wikipedia article.