While there are tools for doing backups as formal backups as well as rules to conform with system administration best practices, that's probably overkill for what normal people need to do. Note that even if you do keep files on a server that gets backed up, the server backups are only for disaster recovery and not for restoring a file you accidentally nuked. Besides, if your files are important to you, make a backup. I generally do mine, monthly or whenever I made some big changes I don't want to lose.

PC

To make backups easier, I never let programs store files in the default location (frequently the Documents and Settings folder). Rather I keep all my stuff in one directory (that contains appropriate subdirectories of course). On my home PC this is C:\withers. Then I just copy that directory to some external storage device. There are at least three good choices depending on what you're backing up and how big it is. You can use a USB flash drive. These are getting bigger and cheaper all the time. You can buy a 4GB one for $30 to $60. You can also use an external usb disk. You can get a 300GB disk for around $100. A third choice is to burn a cd or dvd.

Each PC in the house 4 lab also has a DVD burner and a program call Nero that interfaces with it. CD's hold about 650MB and DVD's about 4.5GB. Here is a note Bob Debula sent earlier this year on DVD burning.

All of the Grad lab (3892, aka "the long building") Dell PCs have now been upgraded with DVD burners. These new internal DVD drives can read and burn CDs and DVDs, as well being able to do LightScribe labels. These drives came with licensed Nero 6.6 burning software, which was also installed on all the Grad lab PCs. The Nero software has all been updated to the latest available release of Nero 6. To use the Nero burning software, just double-click the Nero StartSmart icon from Windows XP. Nero 6 supports a very wide variety of burning functions and optical media formats for CDs or DVDs. Nero is fairly intuitive to use, but if you require help, basic help may be obtained by clicking on the "?" in the upper right corner of the Nero StartSmart window. More detailed help may be had by clicking the silver arrow on the middle left edge of the Nero StartSmart window. This will show you the clickable Nero product suite manuals for each Nero 6 product. Nero 6 has functions such as Nero BackItUp, to allow you to create CD or DVD backups (Nero has "Back up Files" and a "Back up Hard Drive" options) from a PC, and Nero Cover Designer for creating LightScribe or printable labels (jewel case inserts). Many common functions, such as copying CDs or DVDs, creating data CDs or DVDs, creating audio CDs, or burning ISO images to CDs or DVDs, are also supported. The best way to learn about these functions, and all the functions which are available, is to simply start up Nero StartSmart and run the mouse over the various function icons it presents, which will display a comment bubble showing which functions each particular icon can perform and displaying icons for the subfunctions available.

A list is included below detailing this new DVD burners' support for various optical media, such as CD-R and DVD+R, as well as the speed with which the drive can (theoretically) write to them. Most of my use has been with CD-R or DVD+R media. I would probably recommend DVD+R over DVD-R media as it seems to be a bit more broadly used and supported these days. The price difference for rewritable optical media (CD-RW, DVD+RW, etc) is usually great enough that the write-once media (CD-R or DVD+R, for example) is much more cost effective (DVD+R media has been available at times for as little as a quarter per disc or even less). CD media has a capacity of about 700MB, DVD media has a capacity of about 4.7GB.

This DVD burner also supports dual layer media such as DVD+R DL (which has a capacity of around 8.5GB). Dual layer media is still rather less common, and generally far more expensive, than just purchasing twice as much single layer DVD+R media. The place where dual layer media is most commonly used is for video DVDs (many commercially produced movies are recorded to dual layer media).

LightScribe labeling requires purchasing discs which are specifically made to be burned in LightScribe capable drives (they are "readable" in normal drives, and "writable" as well, though that would be an expensive way to go if you did not actually want to LightScribe label the disc). You have probably already seen LightScribe labeled CDs if you have borrowed software distribution CDs from me over the past several months (some folks had trouble reading my writing for things like the product keys, so they are now burned in a readable font on the CDs themselves along with other relevant information). Labeling on the disc is created by flipping it (a LightScibe media CD or DVD) over when prompted to do so during the CD/DVD burning process. The more complex you make (using Nero Cover Designer) the LightScribe label, the longer it will take to burn it to the disc ("best" quality will also take longer than "normal" quality, which in turn will take longer than "draft" quality). A "best" quality LightScribe label consisting of text (monotone graphics can be done, but slows things even more and varies as to appearance) will probably take, on average, 15 minutes or so using "best" quality. Given the somewhat higher cost of the media and the reasons for direct disc labeling in the first place, I have almost always found it preferable to use "best" quality and wait just a little bit longer for the finished disc. For things like data backups, I would probably just use ye olde sharpie felt tip marker to write a label on standard DVD+R discs.

The media stated to be supported for the new drives:

READ Speed
WRITE Speed
DVD+R18X
DVD+RW8X
DVD-R18X
DVD-RW6X
CD-R48X
CD-RW32X
DVD+R DL8X
DVD-R DL8X
DVD-RAM12X
DVD-ROM16X
CD-ROM48X

These new drives are probably noticably faster the the original Dell CD writers that were in these PCs at creating CDs also.

Obtaining the optical media for use in these drives is up to the individual. I have had good luck thus far (no "coasters" that were not my own fault) with Verbatim DVD+R and Verbatim LightScribe DVD+R media and HP DVD+R LightScribe media. Many name brand media seem to work just fine, but sometimes the "bulk" media that is store branded can be problematic. In reality there are far fewer actual media producers than "brands". Some of those media producers are far more meticulous in making their products than others. Some "brand name" media can vary between lots as to who actually produced the disc. As far as LightScribe media is concerned, it comes in very few "brands" thus far (HP, Verbatim, and Memorex). I have not had any problems with HP or Verbatim LightScribe media, and I have not yet used Memorex LightScribe media. Your experience may vary considerably.

As a side note, these LightScribe DVD burning drives (the same model as just installed) may be had as inexpensively as $35 each from online vendors and often come with burning software, such as Nero, bundled. Given the fairly low cost per MB of DVDs as a backup media, this may be one of the more effective ways of backing up your PC data economically these days.

Sun

On the suns, the three primary tools are ufsdump, tar, and gtar.

dump

You would only want to use ufsdump if you're doing an entire partition. We jumpstart all the suns so unless you've made alot of system configuration changes, it probably isn't necessary. I have scripts you're welcome to if you want to do a ufsdump. Use ufsrestore -i to search through a ufsdump backup tape, and to select and restore the appropriate files and directories.

tar

If you only want to back up a single directory (like your home directory) then tar is a better choice. Tape devices are usually named 0, 1 or 2. So the correct device is then /dev/rmt/0 for the 0th device. You can see what devices there are using ls /dev/rmt. If there are multiple devices, You can find out which is which using mt -f /dev/rmt/0 status.

To copy a directory to tape, use tar cvf /dev/rmt/0 [your directory]. The c means "create", the v means "verbose", and the f means "file" though the f in this case refers to the tape device. To copy from tape to the current working directory, use tar xvf /dev/rmt/0. To get a table of contents use tar tf /dev/rmt/0.

Note that tar will not copy dot files and it will only copy links not the link target. I don't know of a good way to tar dot files other than to make a list of them along with other directories you want and then use the -I argument to tar (note you wouldn't want to tar .* because that would include . and ..; the current and parent directory). You can use the -h switch to tell tar to follow links and include the targets rather than just the links themselves. Note that this could cause problems on a restore (i.e. by filling up the disk) so I'd probably make a second tape archive of the link target.

You may have noticed that there are more 0 devices than just /dev/rmt/0. The other 0 devices are the same tape drive, but modifies the default behavior. For example, /dev/rmt/0n is the "no rewind" device. Using that one will cause it to not rewind after reading or writing. Using the 0c tells the tape drive to compress the data its writing to tape. This will slow things down but could dramatically increase what can be fit on the tape (particularly if you have alot of ascii files). Using /dev/rmt/0cn will both compress and avoid rewind (mt -f /dev/rmt/0 rewoffl will rewind and eject the tape).

There are many things you can do with tar. See the man page. Also see mt fsf to learn more about putting multiple tape archives on a single tape device (though be sure to label it well if you do this so you know what order to feed the volumes).

gtar

Unfortunately tar doesn't span volumes. It will only work on one tape. Fortunately, if the data you want to back up is larger than a single tape, you can use gtar (the GNU version of tar). Here is a command I've used before:
gtar -c -p -f /dev/rmt/0c -M -v /gaia/elwe/d1

The -c tells it to create the archive on the device listed after the -f. The -p tells it to keep the existing permissions of the files rather than convert them all to the umask of the person running gtar. The 0c device uses compression. The -M says to make a mulit-volume archive if necessary. And the -v is verbose so I can see what its doing and monitor progress. Like tar, the gtar switch -x, is the reverse of the -c. Use gtar --help for more info.