Effective System Backup
By Steve Rose
Thursday, October 24, 2002
Backup Alternatives (from an Extreme Tech Forum exchange, edited):
There are a lot of backup alternatives. Any are better than not backing up (with one exception: Some backup systems seem to be working, but when the emergency occurs and you have to restore, it turns out they were making bad copies.) However, there is one way that is particularly inexpensive, fast, and reliable. Ironically, the same technique applies to upgrading your system as to backing it up, so let me start there:
Buy your new, larger hard drive, and use a utility like Ghost or Drive Copy to make an image of your current drive. These utilities will copy all of the files, including the bootstrap files, and automatically proportionally partition your new drive so that it matches the allocation on your old drive in terms of percentages of the disk space allocated to different logical drives. If you are like most (e.g. me), you have only one partition. No problem, the entire space on your new drive will be available on the single partition.
Hide your old drive. Do not under any circumstances do an operating system upgrade on the old drive. It is guaranteed to fail by Murphy’s law alone, and you will lose your programs and data. Do all experimentation on the new drive, keeping your old info and programs intact on the old drive, so that you can copy it again if needed.
Chances are that the new drive will cost a fraction of the overall upgrade when you consider your time, and be faster and much larger than your old drive. Think of the time you have involved in creating, installing, and downloading the files and programs on your old drive. Why risk those hundreds of hours? How much is your time worth? If it is more than fifty cents an hour, buy a new drive if you intend to upgrade your operating system!
If there are any problems with the upgrade, recopy your old drive and do it again! You won't be violating any license argreements, as the new drive replaces the old in the same machine. Further, once you are done, you can mount the old drive as an additional drive in your upgraded machine.
To do backups, buy another drive, equal to or larger than your newly installed drive. Get a removable drive holder for the second drive, and use the same copying utility to make an image of your primary drive. There is no less expensive media, nothing faster, and nothing more reliable than a hard drive for backup. It can be immediately verified, and has its own electronics, and can easily be removed from the premises. You can make multiple backups and keep at least one off premises at all times this way (the drive holders are inexpensive). Best practice: Turn off power before installing or removing drives.
Why Hard Drive Backup is the Best Alternative
oThe failure of a drive does not block access to backup media, as is the case with removable media drives. Further, future access is not blocked because the medium has become obsolete and drives to read it are no longer available.
o Verification is easy. How many folks have you known who backed up religiously to tape, only to find out when they tried to restore that none of their "backups" were good? Religious backup to tape is the only way to use tape, as lots of prayer is involved. Tape has so many other negative attributes (e.g. linear vs. random access, very poor archival qualities) that it is a poor choice. A sealed hard disk is likely to be much more reliable in the long run than any other medium (with the exceptions of stamped or printed media), although it would probably be a good idea to fire it up a few times a year rather than having it sit idle.
o Any attempt to back up data from contemporary applications will fail, as each application has too many dependencies and unknowns. This is particularly true under Windows, where program dependencies have been intentionally obscured for copy protection. Where are the data files stored? Are any other files (or the registry) modified during program operation? Are the data files specific to this revision of the program, such that the exact same version of the program must first be installed? Even if you install the same program version, is restoring the data as simple as copying back the files (e.g. not Outlook Express)? If you copy the program as well as the files, are you sure you copied all of the relevant DLLs from \windows\system and elsewhere? Even if the program has a built in backup procedure, do you want to go through this for each of your programs? An image backup always works as well as the original.
o The "backup" serves as a complete replacement drive, if there has been a hardware failure. Remove the old drive, install the new drive, boot, and continue. Or just leave the old drive in place and change the ROM BIOS to boot from the backup drive. The rational approach is to create several backups and rotate them, with one off premises. The purpose of the off premises drive is not just in case of physical catastrophy -- it also helps to prevent the all of the backups from being destroyed by the same logical error that caused the initial problem, as it provides time to think. The first rule should be that unless the problem is caused by a hardware failure, a backup image should be made of the backup drive you are about to promote to primary drive.
o Hard drives have continued to drop in price to under $1 per Gigabyte, significantly less than other magnetic media. And that price includes the electronics. While optical media (e.g. CDR) is even less, the HD is one large medium that is much faster, and therefore much more convenient for backup.
o An image backup to HD is also trivial to use for file by file restore.
Backups while Running Under Windows
If you have to make a file by file backup while running under Windows (e.g. the backup medium is only recognized while Windows is running), you won't be able to copy the windows swap file (generates a file in use error). Go to Explorer, select drive C, then select the Windows directory in the right window (single click). Then Edit, Invert Selection, and copy the remaining directories and files from drive C to the backup drive (drag them all at once). Later, create a Windows directory on the target drive, and double click the Windows directory on the source drive. Select the windows swap file (Win386.swp). Go to Edit, Invert Selection, and drag the rest of the files as a group to the newly created windows directory on the target drive. This procedure does not create a bootable image backup, but it will copy all of your files to the backup disk.
Portables
There are several programs for image backup, such as Ghost, DriveCopy, etc. On a portable computer, there is Apricorn's EZ Gig, a PCMCIA IDE interface for 2.5" drives and corresponding software. There are others. The EZ Gig is great since you can provide your own drive (much less expensive), and their software boots at the DOS level and recognizes the PCMCIA drive. On the down side, their software boots from floppy and is copy protected. If you can't boot from their disk, you are out of luck. Also, their PCMCIA card is slow. A card bus implementation would be better, or software that would recognize a Firewire or USB2 drive. Another approach for portables is to move the old and new drives to a desktop with 2.5" to 3.5" adapters ($6 to $10 each), and use a desktop software solution (in this case you boot from floppy or CD, or a 3rd HD, so that you don't have to modify the portable's HD OS to accommodate the desktop's hardware environment).
Removable Drive Holders
Removable HD holders are readily available now for 3.5" desktop drives. Choose holders that can be used for UDMA 66 or higher, as they seem to use better connectors. Drive trays are not interchangable between manufacturers, so buy several at once rather than having to locate matching trays later. While they are not perfect, I've used them happily for years. Don't try hot swapping -- while I have not destroyed any drives this way, rebooting is generally required to recognize the drive anyway, so do it right in the first place.
For portables as well as desktops and servers, there are new alternatives for removable drives, with both Fireware (IEEE 1394) and USB2 drives being worth using (USB1.1 drives are way too slow for gigabyte sized backups). However, unless your image backup program knows how to use the 1394 or USB2 ports (image backups work at the DOS level, so Windows capabilities are irrelevant), you will be confined to doing file by file backups as described above.
RAIDs and Backup
It is a bad idea to use RAID for backup (of course, we are talking about RAID 1, or mirroring). While it is great at keeping systems on line in the case of a hardware failure, the most common cause for needing to go to a backup is a logical failure (software or user). A RAID 1 system instantly copies the flawed data to both drives, rendering them of equal (diminished) value. Even if you use RAID 1 for hardware reliability, all normal backup rules still apply
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The remainder of this article is directly from the ET Forum, with excellent advice from the other participants.
From EGREGIO to SR:
Having worked for EMC, I certainly agree with Steve Rose that mirroring your disk has advantages, but it also has many disadvantages and limitations:
Precisely since the second drive is completely synchronized with the first, it doesn't protect you at all against software problems, malicious damage (viruses), or user error (probably the most common need for a backup). Rose suggests having several hard drives that you swap in and out daily, but that sounds awfully cumbersome to me. And since the copies aren't incremental, you need a whole drive for each snapshot.
It's true that the cost per raw gig is low, but since the snapshots aren't incremental or differential, you are paying a lot of money for redundant information. The most precious kind of data on your system is user-generated and incoming email, and you can only type so many characters per day and read so much email a day. Why take 30GB snapshots when only 1MB actually matters? Yes, the 30GB will help you recover quickly from hardware failures because all your apps are completely set up and so on....
If you want to be really paranoid about failure modes, if your power supply fails high (that is, a short or whatever causes the internal electronics to see something close to line voltage), it can burn out everything in your case, including both hard drives' electronics. Again, being paranoid, if your computer is stolen, the second drive goes with it....
If you do swap the drives in and out, one advantage Rose doesn't mention is that it becomes VERY easy to compare two states of the directory tree, and restore selectively because of the very high access and transfer speeds of disk.
So what do I suggest? Well, I'm afraid I don't know the market for PC backup and archiving solutions, but ideally I'd like my backup to be real-time and off-site, that is, some sort of networked journalled file system. It should interact cleanly with applications that keep database files open for a long time (e.g. my email file in Outlook, Access databases). You still want an on-site full dump for easy restores, maybe managed as a weekly full dump and daily differentials.
Any products out there that can help me do that?
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From SR to Egregio:
We agree on almost everything. A backup for logical problems can't be a RAID1, as you point out, as logical problems are immediately duplicated to the "backup". By the same token, a "grandfather / father / son" backup approach is called for, since by the time a logical problem is discovered it may already be present on the earlier backup. Also, as you point out, a catastrophic event during a backup can destroy both media, which calls for a second backup generation. I think it is smart to keep a weekly or monthly backup off premises, as well, for a worst case scenario. Using removable drive holders, I haven't found it any more cumbersome than other media.
I also agree that it isn't logical to have to back up 30 GB when 1 MB of stuff has changed. My experience has been like Mrs. Murpy's corollary, though: The law, bread falls with the buttered side down; the corollary, you can't tell in advance which side to butter. I have been burned by archiving mechanisms on a number of operating systems, from DOS to Windows to Palm, with archive bits, time / date stamps, etc. And with an OS like Windows where program operation can result in registry changes, my only successful backups have been whole image backups. By the same token, incremental backups turn excremental when the second incremental backup out of five is defective, preventing restoration of the remainder.
Drawbacks of full image backups include having to take the machine off-line to do the image, which is not possible in some cases. For most folks, though, it can be done overnight.
When a catastrophe occurs, I prefer to make the recovery as easy and fast as possible. Making a backup occurs at a predictable, budgeted time, so I'd rather front load the process. I haven't found the full image backup approach to be more hassle than other backup procedures -- in fact, it is generally less because it always works, whereas other procedures have sometimes had to be repeated the next morning during business hours (notably tape). I've also had recovery problems with other procedures, as recovery always happens under stress. The most important rule, after Backup, is Verify your Backup.
I also agree that a full image backup appears costly in terms of redundant storage. However, when the backup medium costs almost 100 times less (e.g. HD at $1.30 / GB vs. Zip disks at $.80 / 10 MB), this is less of an issue. HD speed of operation is also much faster.
Off site backup is a great potential solution, but it requires an excellent broadband connection if it is to be real-time. I have a friend who uses an Internet based off-site daily backup, and he still swears by it. However, on a recent restore, he lost months of appointment data due to a software incompatiblity, subsequently rectified. During a recent trip I was unable to make an image backup due to a failed floppy (sigh), lost my HD, and installed a new disk and OS. The only way I could find to move my Outlook Express files back once I was restored was to copy the mail files to an intermediate file, then back into my old Outlook Express. Time consuming file by file or application by application restores are a killer under catastrophic conditions.
(I use Outlook Express so that I can look at the raw text of incoming messages (right click, properties, details, message source), as HTML display of messages can load a virus even without opening attachments (simultaneously defensive and paranoid).)
Steve
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Egregio to Steve--
Thanks for your thoughts. We seem to disagree less than I thought.
A grandfather/father/son backup is one way to handle logical problems, another is a full journal of file system activity (except temp files and caches of course).
You seem to have more experience with the problems on PC systems than I do. I don't understand why they work so badly -- as long ago as the early 70's, there were operating systems that did a far better job (Multics, Tenex, etc.). I didn't suggest incremental backups for two reasons: one, as you say, if the second of five is bad, you're in trouble, the other, you have to apply multiple incrementals to get back to where you were. That's why I was suggesting full + differentials.
About cost, I wasn't thinking of Zip disks, which are as you say ridiculously expensive -- I was thinking of CD-R or CD-RW (or DVD when drives become a little cheaper).
If you are doing intelligent journalling, only transferring changes, I don't think you need more than ordinary broadband connections (unless you're doing video editing or something). The question is whether there is good software to do this -- I don't know. Which service was your friend using?
- egregio
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From SOMEUSER to SR:
Although you make several good points, and I do think that drive mirroring is a good idea for a "production" machine (including your home machine, if it contains valuable information, such as your financial systems, or if your information is worth the cost to you), I think that there is something of general confussion as to what a backup is for, and why you need to backup.
Normally, when I have to go back to a backup, it is because someone / something has corrupted a file or has made an invalid change to the file. Since this may not be caught immediately, you may have to go back a couple of days, or even a week or more to get a "good" copy of the file.
IMHO, a good "daily" backup strategy would have at least a two-week period of nightly backups available, with a bi-weekly backup saved until the end of the month, then montly backups available for a year (or more). The cheap way to implement this with production-style hardware is to get a 7-tape changer, then swap out one media set each rotation period, returning the media when it is no longer needed; this way, you only have to buy one set of media each month. (of course, starting out you need 16 sets of media- OUCH!)
This is the only problem that I have with mirroring to a hard drive: I doubt if I could afford to buy 16 copies of my current hard drive, plus a new copy each month... if you can fit your entire backup image on a 20GB cart (~$20 now), you are looking at about $340 worth of media to start, plus a $400 drive. With hard drives, you're looking at a $70 "cart" x 16 = $1120, plus $70 more a month.
Of course, this is just my opinion :-)
(and "good" tape systems can work very much better than the old tape-based systems; I agree: I would trust a travian tape about as far as I could toss it.)
SR to Someuser:
I agree about the number and timing of backups saved, especially where accounting information for a small business is involved and the need for an earlier period adjustment may be discovered late in the accounting cycle. This may be a place where an application specific backup is justified. I've seen several accounting packages over the years that offered a backup and restore procedure for accounting data only. This sort of data also compresses extremely well with Zip, if compression is not already included in the built in backup. (In one circumstance, 20 MB of data compressed to 20K!) Making a CR-R copy of the compressed backup files would probably take only one disc for all but large businesses.
It looks like each installation needs a backup plan that takes into account the nature of the data to be backed up. Some data has historical dependencies that require a deep backup as you suggest, such as accounting data, and customer records. Some things require a daily "work in progress" backup, such as individual documents. Some projects require a "point in time" backup of a consistent set of files (e.g. a web site, or program source). And some files need immediate backup as soon as they are created (creative writing, idea descriptions, and other things that are done on the spur of the moment).
My bias against tape comes from 35 years of videotape experience, and about 15 years of data tapes. However, my last data drive was about four years ago, so maybe things have improved. One perspective that comes from being old: An old tape may be intact, but a drive to read it is no longer available (applicable to all removable media). One of the reasons I like hard drives is each comes with its own electronics. In the very long run, though, the same issue applies: Is a compatible drive interface card available? This is especially relevant as we move from parallel ATA to serial ATA over the next few years.
Cost is interesting: CR-R, seven cents (Office Max, this week), 700 MB, or $.10 per Gig, about 3 MB/sec, easily verified, file by file restore, should be archival (is CD-RW better?), drives are cheap, must be present to win (backup requires multiple media changes, automatic changers are very expensive). Certainty that you will be able to read the backup if needed: High.
Tape, $1 / Gig (per you), speed (your answer here, mine were slow), verification (your answer here, my experience has been marginal), file by file difficult due to linear medium, archival quality poor, drives are expensive but changers are available, unattended backup possible. Certainty of backup: medium (my experience: hit or miss, even with verified tapes).
Hard drives, $1 / Gig (last time in CA, Fry's, $89 / 80 Gig, last purchase, WD 100, $229 w/ $100 rebate), easy verification, easy file by file restore, archival with periodic use (sealed media, independent electronics), passive plug-in holder (it is the drive), unattended backup easy, high confidence in backup.
Another parameter of interest is the style of backup:
Full image: Typically requires running a different OS to prevent file in use conflicts, preventing on-line use (but insuring a "point in time" backup). Consumes time and media. If it is a true bootable image backup to another HD, the backup HD may be instantly substituted for the original disk. May be used for file by file restore as well as full restore.
RAID1: Provides on-line redundancy in case of hardware failure. All logical mistakes are instantly propagated to the backup. However, probably best to protect transient ideas and the last day of work.
Is there a keystroke backup program that preserves the last day or so of input? This with a RAID1 would be of great value to those working on critical projects involving ideas captured at the computer (e.g. a last minute presentation), where the dog always eats your homework.
Incremental: Excremental.
Egregio, please check my assumptions on the following:
Differential: (assumption) point in time full backup, with each subsequent differential backup reflecting all differences from the full, so that only the full and the current differential are required for a restore. A new full backup is done periodically, or when the differential gets too big.
Journalled: Full image, updated from changes, with changes preserved so that the image may be rolled back to a prior state. Typical for off site backups?
My preference, after your input and Egregio's, as well as others in this discussion, is evolving from a hard core full image position to a full (bootable) image with periodic CD-R differentials. This should minimize wasted time and expense, and maximize reliability and convenience.
Please extend and critique the lists! And please expound on positive tape experiences. There sure are a lot of folks using tape, it must have redeeming social qualities.
Aloha,
Steve
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From Nick to Rootsmusic:
There haven't been many truly successful magnetic high-capacity removable direct-access storage technologies beyond Iomega and Syquest drives over the years, though LS-120/SuperDisk should be considered somewhat high-capacity too (certainly vs Zips). Of course, I love my Toshiba 2GB (wish I had the 5GB) PC Card for backing things up on my notebook.
Remember the various higher capacity floppy technologies, like the old 2.88MB perpendicular recording disks in the late 80s, or the 20MB Flopticals from Insite that used laser-etched servo tracks and infrared LEDs to position the head.
Avatar had their Shark removable magnetic drive at 250MB, but I'm not sure what happened to them, and Nomai had a magnetic 540MB magnetic removable back around the time the 1GB Jaz and 1.5GB Syquest Syjet were introduced about 5 years ago.
Today, I still find uses here and there for a quick copy or data exchange with desktop systems around the house with a floppy disk (especially since I have about 800 of them floating around and pretty much holding years of now useless data or apps - like the 30 or so floppies in the floppy distribution of the old MS-Office!).
We've managed to lose floppies on many notebook SKUs (now expansion accessories), but I do wonder how much longer we'll carry them around on desktops, since people have predicted their imminent demise since the mid-90's.
Nick Stam
Senior Tech Director – ExtremeTech
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(SR: One of the interesting things about Nick’sreply is to notice the variety of formats he mentions, all of which are obsolete and equipment to read the disks is no longer available, except the Toshiba PC Card, which is in fact a stand alone hard disk.)
From MBOTHNE to SR:
Steve: Please allow me my two cents worth. First the rotation sequence of the drives must be thought out 'cold and logical'. How much data can you loose and stay in business? Divide that in half. This is the time for 'Father' backups. Divide it again and you have your 'Son' backup time frame. The 'off site backups are done at the same time as 'father' backups, but with at least two different time frames. An A and B backup up set. If you were doing ' sons' once a week, and 'fathers' every two weeks, you would have a month to detect an error on your system or data(virus or bad memory/controller/drive). before loosing enough data to go Chapter 11. Money is the limit to your backup procedure. The offsite never, ever comes to the site to restore from, unless the hardware has been tested and cirtified by someone that it is good. I like your use of the removible drives for the backups. Simple, neat and easy to restore from(make the partition Active and add a bootblock, if needed). I have seen so many companys stay alive by 'pure luck'. One had the 'Off Site' backups on site and when the building caught fire, they were on the other side of the firewall from the computer room(which was totally destroyed). The packs were cleaned(the old removible kind) and installed in new equipment to make new masters and they were running in a rented building(down 3 days total time). If you want a daily backup, O.K. I would add a weekly and a monthly as well. The monthly would be one of two drives, that gives two months grace and safety, off site. Off site is any location that takes a minimum of 15 minutes travel, ONE WAY, to get them. This will give you 30 minutes time to calm down and ask 'Why are you putting them in the system?' If it is not for noral backups, stop and slap your forehead! Make sure all is good first. I know you understand and know this, but so many others do not. It just comes down to money. What is your systems data worth? Now go by the drives to protect it.
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SR to MBothne:
Here Here! Well said, especially the economics and taking the time to calm down, and check the hardware, before inserting the off site backups (or hopefully those nearby). Thanks for your reply.
Steve
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Moving large files from system to system:
SR to Nick:
An interesting alternative for moving large chunks of data from system to system, when a network solution is not available, is a Sony Memory Stick with a floppy drive adapter. It isn't perfect, as a driver needs to be installed (from floppy) for it to be recognized, but it turns the floppy drive into a high capacity (but slow) transfer device. With the use of a memory stick to PCMCIA adapter, it can also transfer data to and from a floppyless portable (and is faster than using the floppy anyway). On a portable, the PCMCIA is recognized as an ATA hard disk, and installed automatically in my experience.
PCMCIA adapters are also available for Smart Media and Compact Flash, and I suspect SD and MM cards. This is ideal for transferring data from a digital camera to a portable, as it is fast and avoids having to carry cables and power adapters. It is also very convenient for MP3s, and moving info to and from PDAs with expansion slots.
Flash solutions don't address your need for larger transfers (e.g. > 2GB). There are PCMCIA to IDE adapters (such as those from Apricorn and Greystone) that allow the use of 2.5" drives as externals without separate power (the Apricorn comes with an external drive box, which I don't use). Both are recognized in the same manner as the flash adapters mentioned above (by Windows, anyway), and don't require special drivers. Notebook 2.5" drives have become much less expensive, with 30 GB at about $170 at Frys (last month).
All of these PCMCIA solutions are slow relative to a CardBus implementation, but I don't know of any CardBus adapters of this type. (Digression into old joke: PCMCIA = People Can't Memorize Computer Industry Acronyms.) PCMCIA speed is comparable to USB1. However, Firewire and USB2 external drive boxes for 2.5" drives have become available in the $60 to $100 price range that are speed demons, allowing the raw transfer speed of the drive to be the limiting factor rather than the interface. There are CardBus implementations of both FireWire and USB2 interfaces for portables not otherwise equipped. Firewire and USB2 can make a huge difference in the transfer rates for external CDRW drives, as well, supporting 24X plus recording speeds.
Not as cool as a 5GB PCMCIA drive or a 1GB compact flash, but a lot less expensive!
Thanks for your visit to memory lane on older drive technologies. I'm wondering whether holographic optical storage, which I've been breathlessly anticipating, are going to go the way of bubble memory -- the drive revealed at NAB by the Lucent spinoff stores 100GB with a 20MB/sec transfer rate, which sounds like a $130 IDE drive. Hope I get to eat my words.
Steve
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To SR from Nick:
Thanks for all the details on the various transfer and storage options. When I was answering RootMusic, I was limiting my discussion to removable magentic rotating media as RootMusic was referring to, I believe, and discussing the usefulness (or not) of the old floppy drives. But you've presented a range of different technologies and options available today that can certainly benefit many people reading this thread.
Regarding Cardbus vs PCMCIA cards (aka PCI-level speeds vs ISA-level speeds), I believe many new "PC Cards" today use Cardbus interfaces -- though you may very well be correct that the cards you mention are still using standard PCMCIA interfaces. The actual PCMCIA interface is about the speed of USB1 (maybe a bit faster), because its signaling is translated to ISA bus signaling, versus translated to PCI signaling for CardBus. And the ISA bus had a theoretical Max of roughly 8MB/sec, versus 132MB/sec for PCI, and ISA devices in an ISA slot usually had a typical sustained rate of about 2-3MB/sec versus 60-90MB/sec typical for PCI card devices (assuming they have full use of the bus), where USB 1.x transfers a little less than 1MB/sec sustained. There are execeptions, as always, depending on device characteristics, levels of optimization, software stack and protocol overhead, etc. And burst rates are different too.
Nick Stam
Senior Tech Director - ExtremeTech
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From Wavy Gravy to All:
Some very good & amusing presentation of all the key points of backup at:
<http://www.taobackup.com/>
Yes, it does at the very end have a little "pitch" but even that's done in an amusing fashion.
Some very good points to keep in mind for anyone doing personal backup, even though it was written with corporate backup in mind.
You may want to go through it twice - once just reading through it (click on the little "tao_right" arrows), but be sure not to miss all the extra reading under the "Click for more information on..." sections.
Definitely something every newbie should read, yet it raises some good considerations for those of us who've been backing up stuff for years...
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Hi Rootsmusic,
The reason I persist in using PCMCIA and CardBus instead of the Association's preferred PC Card designation is to differentiate 16 bit, slower PC Cards (any card called "PCMCIA compatible" in my experience has been a 16 bit card) from 32 bit, fast CardBus PC Cards. (And, of course, the aforementioned joke.) Most folks seem to assume that a "PC Card" is a modern CardBus card, as Nick pointed out, but this is frequently not the case, and requires careful reading of the specs on the box to avoid being burned. For example, a "10/100" Ethernet 16 bit PC Card runs only a third to a sixth as fast as a 10/100 CardBus PC Card, yet may cost the same (or perhaps a small premium). There are still applications that require 16 bit compatibility (I would guess that the PC Card sleeve for an IPaq is one of them). However, all notebooks for the last few years of which I am aware are CardBus compatible.
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Steve, both you and Rootmusic have provided some great info. It truly can be confusing stuff still. But at least we're better off than the early 90's when worrying about the compatibility of our PCMCIA host adapter chips or which versions of Card and Socket services we were running, or whether we had Card Services client drivers, card "enablers", or "super-client" drivers, and in many cases we couldn't hot-swap the cards!! :)
Nick Stam
Senior Tech Director - ExtremeTech
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Amen, Nick! I complain more than most about where we are versus where we should be. In truth, though, I'm amazed by the ease and quality of typesetting, graphics and photography, video, music, and communications that are currently possible. (And spoiled by the ease of installation and configuration.)
Aloha,
Steve
