Timothy Parker
Consulting Incorporated
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Linux Backup Software UNIX users should know the first three rules of system
administration: backup, backup, and backup. System backups are a key (and often
over-looked) part of any system management strategy. While backups are considerably more important in a production
environment where even a few hours of downtime and a day’s lost files are
disastrous, they should not be overlooked for small office or home systems,
either. The amount of time spent
reloading operating system and application software, drivers, user files, and
other data is much more than the time it takes to perform restore cycles from a
backup tape. Even more important, user files cannot be recovered after a crash,
making backups the only way to protect your valuable data. Linux systems range from small, shared-partitioned systems
in your home to those controlling whole offices and Web sites.
As Linux has become a fully accepted operating system, the utilities and
applications available for Linux have grown to mirror those available for larger
UNIX systems. The same is true of the backup software we review in this
article, which mirrors the abilities of the same software’s UNIX versions
completely. While you could rely on
cpio and tar to perform backups, third-party application software packages like
those we review here offer far more convenience, automation, and recovery
options than either cpio and tar can provide.
For many users, these extra features make the price of the backup
software application well worth the investment.
If the recovery process is ever needed after a disk crash or damage to a
filesystem, the investment often seems trivial for the peace of mind it
provides. Do you really need backups?
The answer is moot if you answer yes to a simple question: do you need
your data files? If you can’t
afford to be without the files on your hard drives, you should be performing
backups. The frequency with which
you perform backups, and the manner in which you perform them, is up to you.
But almost everyone will experience a disk problem at one time or
another, and almost every time you’ll find you don’t have a recent enough
backup. Backup often! To test backup software for Linux, we chose a number of
commercial products that have been well received in the past, most of which will
be familiar to readers as UNIX products as well. We tested the software on a network driven by two Linux
servers, one running SuSe and the other running RedHat versions of Linux.
Both machines were single CPU systems with 700MHz AMD Athlon CPUs with
128MB RAM. One was equipped with
SCSI hard drive, CD-ROM, and three SCSI backup devices (Iomega Jaz drive, HP
Surestore 5000i DAT tape drive, and Sony SDC300 AIT tape drive), the other with
IDE hard drive and CD-ROM and an ATAPI Travan tape drive. To ensure the reviews
were fair, we swapped the operating systems after the first round of testing so
each package was tested with SCSI and Travan devices.
Not all the software tested supported both SuSe and RedHat, so only the
supported platforms were tested completely. Our test cycle was fairly simple: the hard drives were
loaded with a variety of applications, software development tools, and a bunch
of data files ranging from large databases to small document files.
To provide incremental changes, we performed sorts and indexes on
database and spreadsheet files daily, although no data was added or removed. We
used each backup software package to backup only the application data files in
their dedicated directories (3.1GB total) as well as the entire hard drive’s
partition (8.3GB total). Where multiple tapes or Jaz platters were necessary, we
performed the media switch without counting the down-time.
We performed our standard backup cycles for two weeks, completing a full
backup on Sunday and Wednesday, and incremental backups (changed files only)
every other day. We timed the backup processes for each software package on each
day. To test restoration processes, we deleted one file a day
(alternating between big and small) and timed how long it took the backup
software to locate and restore the missing file. We tried using each package in the restoration process two
ways, one where we supplied the filename to be restored, and one where we wanted
the software to figure out what was missing and restore those files.
Finally, we tested full system restoration by reformatting the Linux
partitions, reloading a bare-bones OS and the backup software, and seeing how
well we could recover the entire partition from backup media.
Again, we timed that process, too. Throughout the backup and restore cycles, we evaluated the ease of use of each software package, the time it took to initiate, conduct, and summarize backups and restores, the features each package had that were extraordinarily useful or unique, and any problems or hitches we encountered. Some reviews could not be conducted over the full two week testing period because software either arrived late or was in final beta format but the summaries would have been the same anyway. Enhanced Software Technologies’ BRU EST’s BRU (Backup and Restore Utility) is one of the
grandfathers of the backup utility world, having been around for many years.
Over those years the software has matured and aged gracefully. BRU for
Linux is available in two flavors, “standard” BRU which has all the
network-enabled code, and BRU-PE (or “Personal Edition”). BRU-PE is a
non-commercial, non-networked version of the full BRU package intended for home
use. The only real differences between BRU-PE and the full version is support
for networked devices and NFS mounts, backup of raw partitions, a feature to
rename files during restoration, and double-buffered I/O (which affects speed).
To compensate, though, BRU-PE is significantly less expensive than the
full package. We did our main testing with the currently shipping version (BRU
15.1) and also tested a pre-production version of BRU 16.0 (which should be
shipping by the time you read this). BRU comes on three diskettes and installs easily enough
using tar and an install script. BRU offers a command line interface as well as
an X interface but curiously they have to be installed as two different
products. The process takes only a
few minutes following the instructions in the Getting Started guide. After
installing the software, the backup devices must be configured properly
requiring device names and other information about each device (such as capacity
and buffer sizes). The process is a
little hit and miss for someone who’s not a veteran system administrator and
may end up with less-than-optimum settings. The EST Web site has a page devoted
to sample configurations that should help those unfamiliar with the terminology
of tape devices. The documentation
that accompanies the BRU package is well written. We used BRU on both our SuSe and Linux systems and BRU
supports TurboLinux and Caldera OpenLinux as well. Tcl/Tk must be loaded on the
system for BRU to function properly (a pointer to a Tcl/Tk download Web site in
the manual is good but useless for those who do not have a functioning Internet
connection). The X interface makes using BRU easy: click your way
through the process and leave the rest up to BRU.
If you default to the command interface, be prepared to deal with a
multitude of options and flags. The
documentation provides a good summary of command line structure, but most users
will find a few tries are necessary to get a proper syntax laid down. BRU includes a utility called CRU (Crash Recovery Utility)
that provides a boot-from-diskette full system recovery capability.
The CRU system worked well from SCSI devices on our SuSe system, but not
so well with RedHat which apparently doesn’t load some utilities CRU needs to
function properly (the mkisofs utility in particular seems to be guilty).
We worked around this by loading the utility on a diskette for manual
reload. We also ran into problems with the ATAPI recovery diskette system (more
on that in a moment). We ran into a few problems with the ATAPI Travan tape drive
where the device would sometimes seemingly disappear from the system and BRU
would get hung up. We tried using
SCSI emulation (/dev/nstX) and that seemed to solve some of the problems, but we
still had the occasional hangup with the Travan drive.
The SCSI tape devices all performed perfectly. Other than the reported hitches with ATAPI devices and CRU
(which may be fixed by now), BRU performed well. We liked the X interface but found the configuration process
a bit of a pain. Fortunately, it
has to be done only once (usually). The shipping version of BRU 16.0 should also
have a Web based interface, but it was not available when we did our testing.
The full BRU package is a talented backup and restore utility, as we’ve
remarked in previous reviews. The release of BRU-PE does offer a low-priced way
for home users with no need for network support to get a powerful backup and
restore tool, but the lack of raw partition access may bother some users. Using
BRU is fast and easy, and will appeal especially to those who consider backups a
chore instead of a task to be taken seriously. Cactus International Lone-Tar If there’s one name that most SCO users will recognize
(if only from their advertisements) it’s Cactus International and Lone Start
Software’s Lone-Tar. Lone-Tar and
Air-Bag products have been a staple on many SCO systems for over a decade, so
it’s not surprising to see the switch to Linux. We tested Lone-Tar for Linux release 1.1.4 along with
Air-Bag. The product arrived a little late in the testing cycle so we compressed
the test period to a single week. For those who do not know, Lone-Tar is a command line and
menu-driven front end backup and restore utility. Air-Bag is a bootable diskette recovery utility.
The software installs easily enough on our RedHat system but would not
run under SuSe. Cactus doesn’t
support Lone-Tar under any other Linux version but RedHat at the moment, but we
have seen postings on Usenet indicating it works well under some variants like
Mandrake. There no automatic
detection of hardware: all devices have to be configured manually (at least in
the release we tested). We’ve got
lots of experience with Lone-Tar and Air-Bag, and it was nice to see that the
Linux version behaves the same way as the SCO version. Lone-Tar is not the flashiest backup product on the market.
However, it does all the backup and restore cycles with a minimum of fuss
and user prompting. Lone-Tar
supports backups of raw partitions. We
managed to use Lone-Tar with our standard SCSI tape devices without problem, but
the Iomega Jaz drive was sporadic and the ATAPI Travan tape drive failed from
the start even in SCSI emulation mode. The
latter may have been due to some weird configuration requirement, but we
couldn’t figure it out in the time available.
Cactus’ Air-Bag utility allows you to create a bootable diskette that
loads the drives for the SCSI tape device, and reload the entire system with
only a few user prompts. The full
system recovery worked well, if a little slowly. Apart from the device problems, this version of Lone-Tar
worked well. Perhaps we’ve been
using the software too long, but the menu interface is being to look a little
dated especially in comparison to some of the other products tested.
For those of us who use Lone-Tar on SCO systems, it’s nice to see a
familiar friend in the Linux arena. The
pricing of Lone-Tar for Linux certainly makes it attractive. Knox Software’s Arkeia Know Software is a relatively new name in the UNIX backup
world, but Arkeia is going to make waves for Linux users.
If there’s one aspect of this package that stands out immediately it is
the attractive (and busy) user interface. On
the downside, there’s no documentation to speak of included with the system,
only help files and other material on the CD-ROM.
The Arkeia software consists of three components: a backup server, a
client, and a GUI. Arkeia supports RedHat and SuSe Linux, as well as Mandrake
Linux. There are also versions of
Arkeia for many UNIX platforms, but not for SCO (except UnixWare 2.0). The
software components must be installed in the correct order for the system to
work. For a standalone system you
need to install all three packages separately, one after the other (curiously
installing the client before the server). RPM
can be used for installation on RedHat and SuSe. The 10-page installation guide
steps you through using RPM and gives you the order in which you must configure
the software, but leaves the details up to you to figure out.
The end of the “installation guide” concludes with a URL to the
Installation Guide on the Arkeia web site, hardly a useful and user-friendly
approach! On the whole, the configuration process was the most annoying of the
packages we tested. A serial number and checksum are necessary to activate the
software. Almost making up for the documentation and configuration
let-downs is your first view of the main Arkeia interface under X.
Simply put, it’s overwhelming to look at compared to every other simple
interface we tested. The top of the screen is dominated by a set of VU-like meters
that show backup speed and disk and tape conditions. The bottom of the screen has continually updated information
about files being backed up and restored. Controlling
the software is through a dialog that lets you click-and-choose files,
directories, and entire disks to back up or restore.
The process is just like using Windows applications.
There is a command line interface (although finding instructions for it
was a pain), but why use the command line with such an entertaining GUI to work
with? After staring at the Arkeia
GUI for a while, you realize it’s really silly to watch the meters show backup
rates and all the other bells and whistles that are offered, and it probably
will get old very quickly if you use Arkeia on a daily basis, but the interface
sure is fun to watch the first few times! The Arkeia backup system is actually quite powerful beneath
the flashy front end. You can
perform network-wide backups from many different platforms, partitions, and
operating systems with ease. You can cram multiple backups from different
systems on the same tape. You do have to go to the trouble of setting up backup
pools, libraries, and so on (much like Windows packages like Seagate Backup Exec
and ArcServeIT), but this is usually handled only once. Like the Windows
packages just mentioned, Arkeia forces you to use the proper tapes at the right
times: simply plopping in any tape for a quick backup won’t do. You might get
the impression from this that Arkeia is a large corporation’s solution only,
but there is a stripped down single server version ideal for home or small
office use. Arkeia relies on generic SCSI devices for tape device
control. Our SCSI DAT and AIT drives worked perfectly, but the SCSI Iomega Jaz
and IDE ATAPI Travan tape drive caused problems and could not be used with
Arkeia (even using SCSI emulation modes). Once
you get in the habit of using the right tapes in the right place (and carefully
labeling everything to prevent problems), Arkeia proves quite easy and friendly
to use through the X interface. The command line mode can be used but we found it
frustrating. Our overwhelming opinion of Arkeia is that it is out of
place on a single machine or a small network.
The software seems ideal for larger systems with network storage devices
scattered about. The Linux single
server version is worth looking at if only for the X interface, but as mentioned
earlier there is a solid backup and restore engine behind it.
If Knox Software can put a decent set of manuals and some single-button
backup or restore capabilities into Arkeia, this would be an excellent
contender. The price for a
single-server setup is competitive. Microlite BackupEDGE BackupEDGE is a well-known UNIX backup and restore utility
that has received good reviews in our pages and those of other UNIX magazines.
The version was tested (01.01.08) is an incremental release over the one we
tested a few months ago. The software was in final build for release when we
tested it and should be the same as the commercial version.
The BackupEDGE package includes two components, BackupEDGE for backups
and RecoverEDGE for emergency crash recovery. Documentation with BackupEDGE is
very good. The CD-ROM that accompanies the BackupEDGE package includes
binaries for SCO OpenServer 5, UnixWare 7.1, and UNIX 3.2v4.2 as well as Linux
2.x versions. BackupEDGE ran on
both our SuSe and RedHat test systems, and has been tested on Corel Linux,
Caldera OpenLinux, and TurboLinux Workstation as well. The BackupEDGE software
installs easily enough from CD-ROM . The
release we tested adds a new installation wizard to BackupEDGE that
automatically detects tape devices on your system, eliminating the need to use
device names and numbers. The
wizard successfully detected all our SCSI devices although it didn’t get the
Travan IDE tape drive (which is a known problem with this late beta build, as
we’ll discuss in a moment). BackupEDGE uses a character-based menu (no X interface is
available) for all tasks and the menu is quickly learned and fast to use.
You can also use a command line interface for scripting or simply typing
commands, but keeping track of options and arguments can be difficult at times.
BackupEDGE can handle raw partitions, even for operating systems that are not
natively recognized by the operating system performing the backup.
This allows complete partition image backups and restores for entire
disks that may contain multiple operating systems. The RecoverEDGE software that is bundled with BackupEDGE is
going to be a key part of the package for most users. RecoverEDGE uses a set of crash recovery diskettes to load a
minikernel and device driver for the tape drives, and then allows a complete
system restore from the booted diskette. The software makes recovery from
crashed partitions and hard drives almost trivial. BackupEDGE has several features that we’ve noted in
previous reviews as being useful and noteworthy.
The most important is probably Fast File restore which allows for
restoration from anywhere on the backup media very quickly, thanks to indexing
of files in a tape database. There’s
also an algorithm that helps position the tape quickly to the approximate
location of the file, and then conduct the search for the file at normal search
speeds. Also noteworthy is support
for tape autochangers. While we did
not use any autochangers in this particular review, we have used DAT
autochangers with BackupEDGE before and loved the convenience of having a full
week’s worth of tapes automatically loaded and ejected. The only problem we encountered with BackupEDGE had to do
with our ATAPI Travan tape device, which BackupEDGE couldn’t access properly
every time and the installation wizard couldn’t pick the ATAPI device up
cleanly. Microlite is aware of the problem and it should be fixed in the final
release of the software. All the
SCSI devices were accessed perfectly. Other than this minor teething problem,
BackupEDGE performed flawlessly and remained one of our favorite packages for
restoring files thanks to the Fast File Find feature. Merlin Software Technologies Perfect Backup+ Merlin Software Technologies is an unknown to many SCO
users because they concentrate on Linux backup software (although there is a SCO
version of Perfect Backup+ available now).
Perfect Backup+ is their primary product. While the backup software
market is a tough nut to crack with established companies like EST, Cactus, and
Microlite well know, Merlin appears to be making decent inroads. Perfect Backup+ worked on both our RedHat and SuSe systems,
and support Corel, TurboLinux, Mandrake and Caldera Linux as well.
Because the software was designed for the Linux market, it takes
advantage of that operating system’s features in most aspects of the system.
Installation is by package manager as an RPM package, for example, or
through the more traditional use of install scripts after mounting the CD-ROM. The installation and configuration process take a few
minutes. Especially helpful is a detection wizard that snoops out backup devices
and takes care of the configuration of these units for you.
You can manually configure devices, too, which is necessary for many
network tape drives. Documentation is a spiral-bound manual that is good, but the
organization and detail level could be a little better. The interface to Perfect Backup+ is through an X dialog,
although there is a fairly simple command line mode available for routine tasks
and a character-driven menu for X terms as well. A set of one-click buttons lets
you launch backup and restore cycles with a bare minimum of effort. If you need
to override defaults, menu items allow you to do that, too.
A set of “predefined backup packages” target specific applications
and their file storage locations and makes backing up these applications a snap
(although the set is limited to common application suites like WordPefect for
Linux and Applix). Perfect Backup+ detected all our devices without a hitch,
including the ATAPI Travan tape drive that caused most of the other packages
problems. Autochangers are also
detected (at least the HP DAT autochangers we tried). A nice feature of Perfect
Backup+ is that any tapes created using the tool can be used by any UNIX cpio
utility, allowing recovery of tape data on systems that do not have Perfect
Backup+ installed. Backups of raw partitions are supported as well. We failed to find any weak-spots with Perfect Backup+.
It handled all our tests without a hitch as well as used all our media
properly. The only possible
complaint we would have is the speed of restore operations, which wasn’t up to
those of Microlite’s BackupEDGE, for example.
But then, we’re nitpicking. It’s
easy to see why Perfect Backup+ is becoming a popular backup utility because it
seems to cover all the bases. Maybe
this is one of those diamonds in the rough you occasionally come across. The
price is certainly fair for the network-capable tool you receive. Wrap-Up There’s a wide variety of tools and capabilities in the
packages we tested. It’s nice to
see old familiar products from SCO in the Linux arena, as well as the newcomers
like Arkeia. The most expensive
package in the tests, Microlite’s BackupEDGE won all the speed tests, and
along with Perfect Backup+ had the best configuration wizards of all the
products. The most stunning
interface (by a long shot) belongs to Arkeia, although it’s ultimate utility
remains to be seen with long user testing.
Merlin’s Perfect Backup+ is notable for it’s Linux-centric approach
and inclusion of all three interface types. Which of the products gets our Top of the World? Lone-Tar seems to be a little dated and slow compared to the others. The remaining tools all have high points, but the bottom line comes down to Microlite’s BackupEDGE for its speed and flexibility, although for the budget minded where speed is a secondary consideration, either Arkeia or Perfect Backup+ will do just as well. Lone-Tar Summary: The classic Lone-Tar and Air-Bag package finally available for RedHat (only). Device support and limitation of Linux distribution support mars the product at this point, but it’s bound to get better. EST BRU Summary: Sporting a low price and an X interface, BRU-PE is attractive for home users. Configuration can be touchy, as is the new crash recovery utility. BackupEDGE Summary: Between BackupEDGE’s features like Fast Find File and RecoverEDGE’s ability to restore your entire system painlessly, this is a winner of a package. Arkeia Summary: Fancy GUI hides a corporate-strength backup engine. Highly capable, but lack of documentation caused us conniptions. Perfect Backup+ Summary: A sleeper of a product. Excellent interface options, great configuration wizard and
competitive pricing.
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