Answered By: Thomas Adam, Chaz Peters, Karl-Heinz Herrmann, Ben Okopnik, Robos

I'm trying to backup my Linux installation with tar, using a second hard-drive in my system, rather than a tape-drive or CD. The trouble is, I have a 2-GB file size limit on the destination (It's Fat32, so I can also use it for Windows backups), so I have to do it in a lot of little chunks (even with compression). Is there another solution to this, either a fancy shell script, awk script, or some combination of tar options that would produce the multiple destination files I'm looking for? If I keep doing it manually like I am now, I know I'll never maintain an up-to-date system backup like I should. I've found tape options for tar that control multivolume backups, and tape length, but nothing for multiple files.

[Chaz] Backups can be a pain, especially ones that require manual operation. I like to automate them as much as possible. The following is a script I made for Kathy's Debian machine. Usually I prefer to backup over a network to another machine, however she has dialup and no other machines on a LAN. I use rsync because it's fast and works well. rsync is a file transfer program capable of efficient remote update via a fast differencing algorithm. This program is run once a week via cron, it works very well for hassle free automated backups as long as you have enough disk space. If you require compression, this is not what you want. I do not recommend using compression for backups, compression reduces the chances that the data will be recoverable.

See attached backup-weekly.sh.txt

An example of what I'm doing now:

tar zcvf /windows/s/suse/back_tbrown.tgz /home/tbrown

Oh, I tried the Suse backup/restore function, and could not restore the resulting files. The .tar.gz files within the .tar archives (don't know why they did it that way) seem to be corrupted. So, I figured I'd do it myself.

[Chaz] SuSE, sorry the dpkg part of my script won't help...

Note the script lacks a secondary archive, that could be disastrous in a few cases. We do have an older backup on CDR and at some point I would like to transfer it to a laptop or something for other more recent off site copies. She can also selectivily transfer files via dialup so that I can back them up.

When I get more disk space, I am going to look into using better archival techniques. I have heard good things about Dirvish, a fast, disk based, rotating network backup system. A dirvish backup vault is like a time machine for your data. http://www.pegasys.ws/dirvish

[Thomas] What you can do is something like this:

(cd /src/dir && tar cf - . ) | (cd /dest/dir && tar xvfp -)

where /src/dir is the directory you're starting from, and /dest/dir is the final destination that the files (dir's) will end up to.

Since you say that this is going to a FAT32 volume, that will not preserve file permissions. The only way you can achieve that is by making a tar file.

Thanks. That's why I didn't just cp the directories over.

[Thomas] Your other option is to make an archive and burn it to CD. One thing you might want to try though, is you are going to make a tar archive, run it with the "j" flag when you create it. That'll use bzip2 and might compact some more space.

[K.-H.] You might have a look at afio instead of tar. It's more robust against data errors in the archives then tar and from reading the manpage I'm not quite sure if you can specify archive-filenames which are automatically numbered for multivolume. If not you can still automate things with the "promptscript" option. You archive to a specific dummy file, the script will mv/rename it to something useful and (number, date,...) and continue. To get rid of the prompts (or answer them automatically) should not be that difficult.

Be careful to read the basics: afio wants a list of files to be archived piped in on STDIN.

This might be a good startingpoint (no multivolumes, add that yourself):

find /var -xdev -print | afio -v -o -Z -T 5k -b10k  ARCHIVE.afio

[Ben] Make your giant tarball, then use the 'split' utility to break it up into chunks. When you're ready to use it, just 'cat' all the pieces in order (which is how they'll be named by 'split') into a single file that you can untar. As someone mentioned, 'j' rather than 'z' gives you even better compression on large files.

That would work fine, except that the tarball is too big to be created on the destination file system in the first place. What I'm looking for is some way of creating a lot of smaller tarballs right from the start.

[Ben] What I meant was to create it on the "source" system, not the "target" one, then split and transfer. However, you can do it "in flight", too:

tar cvzf - * | split -b 100k backup-01-15-04

[Thomas] Since the destination is not a Unix system, the use of the "-p" flag to preserve permissions is a must in this instance.

[Ben] It's not really relevant to the host OS; the permissions that matter are "inside" the tarball. However, you're right anyway - in a backup,

[Thomas] Indeed.

[Ben] permissions should be preserved, and I lost track of that in generating a random example of "split" usage. In fact, for backups, the "tar" string should be:

tar cvzpSf - *

(add sparse file handling, as well.)

[Thomas] LOL, I don't know, Ben.... all that Yoga and the like is going to your head, just make sure you:

tar cvzpSf

your linux knowledge

I for one, would be very interested in that tarball...

[Ben] Sorry, even the pieces would be too large to fit on any possible host system. Although there's a lot of sparse files there, too.

[Ben] This will create a load of 100k-sized files called "backup-01-15-04aa", "backup-01-15-04ab", etc. If the destination was a Unix system, I'd suggest piping "tar" into SSH, catching it on the far end and then_ splitting it - all done in one shot.

[Robos] I'd rather use netcat instead of ssh. Depending on the connection certainly (didn't read all). But ssh adds quite a load more to the already busy cpu which tries to to bzip compression on the fly...

I'd love to find out why the Suse backup tarballs won't untar, since Yast2 appears to do the kind of backup I want. I'm overlooking something there, I just know it, since the feature wouldn't exist in Suse if it didn't work.

[Ben] Don't know anything about SuSE backup, but the above should do what you want.

Hunting for new desktop hardware

From Karl-Heinz Herrmann

Answered By: Robos, Rick Moen, Heather Stern

Hi Tags,

I'm hunting for new desktop hardware and getting confused and somewhat frustrated.

[Robos] Me too (sort of)

The best German computer magzine (c't) has of course plenty of tests and recommendations as well as "optimal PCs" for certain usage profiles. My problem is, I want a decent performing raid 5 (burned to often by sudden drive failure).

[Robos] Have that already in the gangway - working flawlessly for several years now. 80GB raid 5.

[Rick] Do you expect to be so incredibly short of disk space that RAID1 isn't an option?

[Heather] Funny you should mention that; I met someone recently who got burned by sudden drive failure on a RAID 1 system - and to their horror, while the other drive was fine contents-wise, it was also in a state where it couldn't be brought up normally to be looked at - expected a twin to be present, and nobody wanted to risk it considering a "mew" drive the master and wiping it. It needed a visit to the drive recovery shop.

RAID is not a panacea - a cure-all - against hardware failure; it merely helps. Usually, a lot. But it's specifically not a solution against slow corruption via software failure. Anyone working with oversized disks should seriously consider their backup-and-recovery plans too.

no -- raid1 would be an option. If some 50GB actual space are there that should be enough for some time, (temp) video data won't need raid1.

With recent consumer boards I seem to have the option of using IDE drives, sure. Cheap huge drive space and all. If I understand the board details right all of the regular ATA interfaces are on the PCI bus -- so a raid with 3 or 4 drives there is hogging the PCI bus. There are SATA interfaces which are not going through the PCI interface but have a separate one -- just Linux seems not to happy with SATA yet and most boards have 2 SATA drives -- not enough for raid5. If I could be sure that a raid1 is running stable and at full speed in Linux with SATA drives hat might be an optin, as SATA brings plenty of disk space for a reasonable price).

[Rick] Huh? RAID1 will inherently be faster than RAID5. But either is fine with the md driver.

That's not what I meant -- from all I heard SATA is still highly experimental and often not supported at all. Most often I heard as problemsolver to switch them to IDE.

[Rick Moen] That's one workaround, of three total.

I'm not quite sure if the SATA drives are connected to the IDE connections for that or if the SATA connections can be used in a compatibility mode.

[Rick] The latter -- where the BIOS supports doing so.

And I also don't know what performance changes that might bring along.

[Rick] Who cares? You use the drive in that mode only long enough to compile a new kernel with the requisite support for the SATA chipset in question.

I've been googling quite some time again and slowly I get an idea on Linux support. libata is providing sata support --

[Rick] More precisely, libata is providing better and broader SATA support.

patch in 2.4, already included in 2.6 but still under heavy development as the latest changelogs and bugfixes show.

[Rick] Correct. However, there is non-libata support for several SATA chipsets in recent 2.4 kernels. (Of those, 3Ware Escalade is supported for a long ways back in 2.4.x.)

I'm not sure about the Via K8T800 chipset

[Rick] That isn't a SATA chipset. It's a motherboard chipset -- always accompanied, to the best of my knowledge, by the VIA VT8237 South Bridge, which does SATA and is supported in libata.

but the nforce3 seems mostly supported (sound seems a dead weight).

[Rick] Nvidia nforce3 is also not an SATA chipset, but rather a motherboard one -- always accompanied, to the best of my knowledge, by a really awful Promise R20378 SATA / software-RAID chip. The sound is indeed provided by a really dreadful Realtek ALC650 chip.

I would run, not walk, in just about any direction leading away from that kit.

There are driver tar packages from nvidia for download (at least partly source, not sure if some binary only parts are in there too). The Sata controller on nforce3 boards seem to be Silicon Image like Sil3112A, Sil3114.

Robos: You said they are supported, do you have pointers for details?

[Rick] That is conceivable, but is not what I've been seeing. It's possible that it's dubious-quality Silicon Image chips in some cases, and awful quality Promise chips in others.

[Robos] Yes, my flatmates experience But he's on holiday so I can't ask him. And I don't really recall any details.

[Heather] I've got one; a buddy just compiled 2.6.1-mm4 and with a couple of stumbles making sure other parts work also, is now ready to fall the rest of the way in love with his Athlon/SATA system, bearing an sil3114 chipset. Statistics on exactly how cool not available just yet

Has anyboy here SATA drives working? Performance? kernel versions? any patches? And on what particular chipset?

[Rick] Best quality: Adaptec 24x0, 3Ware Escalade -- in that order. But you won't find those built into motherboards. Usually, what you find inside motherboard chipsets is Intel ICH5. Which is basically OK.

I don't mind AMD/P4 or even AMD64 (new 3000+ is reasonably priced).

[Robos] OK, I don't have sata drives but I read something about it. It seems (see latest c't) that all the upcoming athlon 64 boards have sata (since it's in their north|southbride) and quite a lot of them already have hardware raid0 and 1.

[Rick] You can read more about it here: "Serial ATA" on http://linuxmafia.com/kb/Hardware

Yes -- the hardware is there -- but as far as I know none of the hardware raids are supported in Linux, and booting Linux off SATA drives which run actually as SATA and not in some IDE-emulation mode is difficult. What I do not know if once a Lniux kernel takes over if they are running as real SATA? Performance penalty for IDE emulation mode? And the boards tested in latest c't all have two SATA connectors, i.e. to few for raid5. Of course I could plug in 1 or 2 additional SCSI disks on the PCI bus with them.

Alternatively I've already plenty of SCSI hardware in the old one, so I would maybe even prefer a decent SCSI setup -- but I can't find a chipset with onboard SCSI controllers -- and if I plug PCI cards I'm again hogging the PCI bus.

Are there any other chipsets besides nforce2/3, i875,....?

[Rick] Sure.

Gods above, Karl-Heinz, what sort of incredibly disk-intensive operations are you planning to conduct?

Well -- right now I've some 32% CPU at full whopping 9MB/s (bonnie 8892 kB/s 31.8 %CPU) from the SCSI raid5 in a Pent. classic board running a K6II-366MHz. Since I am hunting for new hardware I am thinking of getting something decent which I (again) can keep for some time. The old system is running since 1997 after all, with occasional low cost upgrades(like the K6).

My original idea was: Ok upgrade is necessary, IDE is still not what I want (performance trouble with my existing Lap and a DVD burner in the desktop put me off; that cdrecord mess, ide-scsi or not, DMA only with the right block size,...). So how about some new SCSI drives (3 for raid5) and a nice new card (U160 one channel should do as I still have a 2940UW for CD, scanner, etc.) and be done. Well-- the lowest grade (new) SCSI drives I can locate are some 10k rpm 18 or 36GB drives which sustain easily 30+MB/s and peak at 70 MB/s. A PCI bus is getting very much the limiting factor as there are probably more cards in there as well and I'm looking for a way to avoid building a bottleneck into the new thing right from the start. Thats why I tried to ask for info's on boards/chipsets which might have SCSI onboard, preferrably circumventing the PCI bus.

But you are probably right, just ignore the bottleneck and let 100MB/s be good enough. In a year the SATA support will be there and offers a non-PCI extension anyway if needed.

[Rick] The SATA 1.0 spec claims a 150MB/sec limit on bus transfers. Of course, the fastest ATA hard drive manufactured today can, under contrived, artificially ideal conditions, read data at maybe 50 MB/sec, so saturating ATA/100 or ATA/133 sounds very farfetched for a long time to come. (Remember, only one ATA device per bus can be active at any specific time. SATA changes this only by permitting connection of only one ATA device on the chain.

Aren't there any "server-boards" with other specifications? In the price lists here none show up, but a recent acer ad mentioned some "ServerWorks Chipset GC-SL".

[Robos] IIRC Silicon Image chips were good under linux. One of the kernel developers even managed to persuade some hw producer to donate some driver to gpl. Can't recall which one that was, might have been promise.

Any boards/manufacturers using that chipsets (available in Germany)?

[Robos] OK, I just looked on alternate.de and didn't find a silicon image but rather found this: http://www1.alternate.de/html/nodes_info/giea01.html

Regarding their promise chipset I found this:

http://lwn.net/Articles/40899

Can anybody point me to details what this chipset can do (http://www.acer.com doesn't)? Or knows of a nice one (like onboard SCSI [raid] controller bypassing PCI, don't forget the Linux support)? Or at least 64 bit PCI? All the consumer boards showing up in a A4 page (tiny print) of boards seem not to have anything special in that regard.

Am I overemphasising the PCI-hogging? To cite above mentioned c't -- If you run a Gigabit ethernet on PCI it basically saturates the PCI bus.

[Rick] 1. Yes.

Hmm....

[Rick] 2. Using Linux software RAID (md driver) for redundancy, you typically won't even notice the load relative to (say) a hugely expensive Mylex SCSI hardware RAID adapter except during RAID volume rebuilds (if you ever have to do that). In such a case, expect the system to very, very seriously bog down during the rebuild. With the Mylex card, all of that would be handled entirely within the array, with basically no system loading.

Every unclean reboot -- but the raid5 regeneration isn't that bad, even on the old system.

[Rick] I'm talking about when one replaces a failed ATA drive in the array. System will be usable but heavily loaded.

Takes some 10 minutes each 3-5 GB mdX. System is still usable during that time. Rebuilding is on a low prioritiy.

I picked up another thing while reading through kerneltrap mailinglists: It seems most onboard so called IDE raid cards are actually just fancy labelled IDE adapters where the windows driver is nothing but a software raid.

[Rick] Yes. Avoid. Use the md driver, instead.

So raid with IDE raid cards are still software raid unless its the (rather expensive?) real thing.

[Rick] Yes. "Real thing" basically means 3Ware Escalade 850x or Adaptec AAR 24x0.

Promise was explicitly mentioned.

What I'm not sure is if this is for all raid modes or just raid 5.

[Rick] Please see my file. You can sometimes get RAID0 disk-spanning using a BIOS trick.

Simply doubling the writes for a raid 1 can't be that demanding in card logic after all.... Does anybody know more on this? Has anybody used IDE raid controllers? How do they behave?

[Rick] 3. Indeed, gigabit ethernet will strain practically any system, even with jumbo MTU sizes set, and even with a suitable switch and other associated equipment.

So that's true -- but then I've no immediate use for a Gbit ethernet now but I want to keep the option open. I think I'll watch the AMD64 scene for some more time, especially if hardware drivers for something like TV cards will run with 64bit OS.

If all this bleeding edge driver location stuff is getting sufficiently annoying I might even grab some PIII off ebay and just plug my existing SCSI chains in (and swap some 9GB drives in for the 2 and 4.5 one)

Still -- specs on that AMD64 sound nice.

[Rick] Yes, I certainly am with you, there! But I want to jump onto the 2nd generation of Opterons, not the first.

There might be a fair bit of video processing in the near future (as well as the use as home media center with timeshifting and all that stuff) so there will be incoming video streams on the PCI as well.

[Robos] we use a 400Mhz Celi for the (software) raid 5 and it works like a charm. Sometimes my flat-mate and I both stream stuff from there and no clogging or anything. Regarding timeshift: if you use dvb you can easily capture the stuff since it's already in mpeg2 format. No processor usage then. And any recent platter should be able to both record and play mpeg2 streams simultaneously.

I am toying with the idea of buying an athlon 3000+ soon: no intel (they have a too high profit margin for my liking), very performant, rather cheap, 64bit (for what it's worth) which linux (debian IIRC) supports rather good. But stay away from the vobis offering, that sucks

That AMD3000+ is intriguing -- what a small c't article can do to ones minds

[Robos] There was one before, like 5 numbers or so, which dealt with 64bit again 32 bit. You might want to read that before too.

Software suspend troubles

From Ben Okopnik

Answered By: Thomas Adam, Kapil Hari Paranjape

So, I've installed swsusp - two patches over the kernel, flip a couple of switches in the kernel config, and "echo > /proc/swsusp/activate". Hurrah! Cute little screen with a progress bar, etc., and off goes the laptop. Now comes the interesting part: when I hit the power button, I see the Acer splash screen, the LILO message, my cute little Tux, and - the usual kernel load messages flip over to the 'restore the suspend' screen with its progress bar... until it gets to the point where it says "Freezing processes: Freezing remaining tasks." Half a second later, it restarts the restore process, until it gets to the above message... and so on, and so on, and so on. PLOKTA didn't do anything - until the next cycle, where the kernel crashed with a panic (!). I ended up having to reboot using another kernel - lucky that I always have at least two, since I don't trust the newly-compiled ones to always work!

There's no info about this on the Web, at least according to Google; just two hits on the relevant line in the code. I'll have to send some email to the "swsusp" list and see if they can help.

[Thomas] How are you actually suspending it though, Ben? I suspend this way:

echo 1 > /proc/acpi/sleep

Huh? Then you're not using "swsusp"'s hibernation feature, but the ACPI "sleep" instead. It's ">/proc/swsusp/activate", as shown in the swsusp HOWTO. Incidentally, the ACPI "sleep" doesn't work for me, whether 'echo 1' or 'echo 4'.

Yes, you are quite right, the two are different. I really am not sure what to suggest other than ask on the swsusp ML. I am not trying to fob you off or anything, but this kind of thing is quite hard to keep track of... i.e. we don't know what is happening until we reboot, etc....

grrr

Heck, Thomas, I certainly wasn't taking it badly. If the issue is new enough that I can't find anything on Google, then it's off to the developers I go; no one else is going to know anything.

Meanwhile, I've got to juggle the flight school appointment here with my trip to the Polynesian Culture Center (http://www.polynesia.com); I'll probably talk to you all next when I'm back in St. Augustine. Cheers!

[Kapil] There is a nice "comparison table" by Nigel Cunningham regarding the swsusp patches available at swsusp.sf.net.

Basically, there are three ways to get suspend-to-disk working for 2.6 kernels. There are two methods that are in the default kernel tarball. There is also a "swsusp2" patch that can be downloaded from the swsusp.sf.net site.

What is not mentioned (and not configured into the Kconfig scripts) is that the current versions appear to depend on the "module unloading" fature that is optional with the 2.6 kernel.

Secondly, while it is true that

	echo -n disk > /sys/power/state

or

	echo 4 > /proc/acpi/sleep

or

	echo 1 > /proc/kernel/suspend/activate or whatever

should suspend-to-disk, it seems to be much smoother to use the "hibernate" script that can be downloaded as part of the tarball at swsusp.sf.net.

Finally, my own experience with the 1.0.3 patch for 2.4 is that it works quite well. I haven't had as much stability with the 2.6 suspend versions. (Works only while testing but fails when actually required .

Eventually, I'll get around to posting my questions to the swsusp site once I have all the variables sorted out.

Oh-oh. This isn't looking good for the moment...

From Ben Okopnik

Answered By: Robos, Ben, Karl-Heinz Herrman, Jason Creighton, Thomas Adam

X11 and acer laptops ~~~~~~~~~~~~~~~~~~~~

I've got this brand-new Acer Aspire 2003LMi laptop - slick, sleek, and faster than a greased weasel on dexedrine. However... it doesn't seem to be too Linux-friendly. (( Sorta. Here are the details:

I can boot LNX-BBC, and even run X. So far, so good - but this is a really high-res display with lots of fancy goodies. Besides, although I remember LNX-BBC as having some sort of an HD install procedure, it's really not what I want to install here.

I can boot Knoppix. Well, more or less, with a lot of emphasis on "less". It comes up, gets through the KDE stuff... and freezes about 10

[Robos] Try disabling acpi. In my laptop, if I move the mouse and kde wants to look what the battery status is the mouse jumps all over the place. Maybe yours is worse. append acpi=off should do the trick.

[Ben] Interestingly enough, ACPI is what works here, while APM doesn't. I've had to install the entire ACPI kit'n'kaboodle (kernel recompilation, userland stuff) and remove APM to make it work. Don't have suspend going yet, but all the other power management stuff works.

[Thomas] ACPI overrides APM in its functions and callings. On my laptop it works rather well, and coupled with swsusp is a dream to suspend to disk.

To get swsusp going, I cannot do better than to recommend the patch for it from:

http://swsusp.sf.net

A kernel compilation is again going to have to ensue, but afterwards, you can do cool things like:

sudo echo 4 > /proc/acpi/sleep

which will dump everything onto your swapspace.

That does look pretty cool... however, I'm not really all that wild about having to maintain a stable of patches. I might do it anyway - I really want that "suspend to swap" feature - but it just seems like an annoying thing to have to remember in addition to the kernel upgrades.

seconds after I start moving the mouse. "knoppix 2" (console only) works fine. "fbdev", "vesa", etc... none of the servers that I've tried for X work in any reasonable way.

[Robos] What's the graphics-card?

Radeon Mobility 9200 (9M+). New enough that "pci.ids" in the 2.6 kernel (I had to upgrade - just moving the mouse (Synaptics touchpad) would completely lock the machine with 2.4.22!) doesn't have it yet, although the folks that actually maintain "pci.ids" already have it. I'd tried, several times, to use the "experimental" xfree86 server, which supposedly can handle it via the "ati" driver, but no luck - so I'm stuck with the proprietary ATI driver. However, I'm a lot happier with that than Dell's nVidia; at least I know that in a year at most, ATI will release the interface.

[Thomas] Yeah, the experimental xserver-xfree86 package is the one you're going to have to use for this. I apt-get'ed it the other day.

There are four partitions on the new machine's HD: Wind0ws C:, Wind0ws D:, "suspend", and... ready for this?... Linux. I kid you not. This gadget has what's called "EFI", which I just happened to read about the day before I bought it by pure coincidence (I had no idea that this machine would have it) - it's a BIOS "replacement" that allows much easier pre-boot programming. What these folks have done, clever buggers that they are, is create an app - two of them, really - called "Arcade" (plays VCDs/DVDs, shows your picture repositories, etc. - sound familiar? Think "MoviX", etc.) and put a button on the front of the laptop. When the 'top is _off,_ pushing this button fires up "Arcade" without starting Wind0ws. When it's on, it fires up a Wind0ws app that looks exactly the same. Is this cool, or what? The way I found out

[Robos] This sounds cool. I heard about it but quickly forgot again.

that it was Linux is by running LNX-BBC and looking at the partitions. When I saw "/bin", "/boot", "/etc" and so on, I thought I was having a brain cramp... took me a bit to figure it out. Aside from that, though - obviously, FIPS won't work with this rig. What I need to do is shrink that first partition (Wind0ws) and put Linux into the newly-created second partition (I don't want to just blow away Wind0ws - there are a few gadgets here, such as a built-in SD/SmartMedia/etc. card reader that are going to take some research

[Robos] I'd say they connected this to the internal usb plug and so this should be easy to get working: enable "probe all LUNs" in the scsi section and then it should show up with scsi-emulation on. This is at least how my 6in1 card reader shows up when I plug it in (is external)

[Ben] before I can use them under Linux.) I wouldn't mind reinstalling Wind0ws after tweaking partitions - but all I have are "recovery" CDs (which will, presumably, restore the system to exactly the way it is now.)

[Robos] partimaged? Have some place to put the image? And I have had the experience with my backup-partition that when I did run it (when you activate the playing-back mode in the bios) it started dos and ran the win installer - LOL. But this way I was able to keep my partition the way they were and have a c: which is still fat32.

Hmmm... I just thought of something. I could blow it all away, install Linux - I'd have at least console-mode stuff, which would be sucky but workable, and copy everything over from the old machine. Then, when I come back, I could buy an external HD for backup, copy it all off, reinstall Wind0ws, and be abck to the same status. Hm. Frankly, this sounds really last-ditch. Worst of all, the new 'top has no serial port, so I wouldn't be able to use my cell phone to connect to the Net.

[Robos] Does your cell-phone have irda? Believe me, this is rather easy (if your acer has irda too and this is supported). I was surfing in my holidays back in the spring with my siemens ME45 lying beside my thinkpad r31. Connectivity!

[Ben] I did too. Didn't work for me.

[Thomas] The first thing I could be inclined you did, Ben, is provide your "lspci" output, along with "lspci -n". What you should probably ensure is that your PCI entry is valid for the detected card.

On my laptop, I have:

00:02.0 VGA compatible controller: Intel Corp. 82852/855GM Integrated
Graphics Device (rev 01)

Re-run:

dpkg-reconfigure -plow xserver-xfree86

and when prompted for your PCI entry add

PCI:nn:nn:nn

where nn is your numbers from the correct entry for your card, but they HAVE to be in decimal format. lspci gives you them in hexadecimal and do you have to convert them. Using my example then...

PCI:00:02:00

I want you to try VESA this time, Ben. See if that makes a difference.

However without knowing much more information about your card specifically there is not much more I can do You should ensure that you have AGP support compiled into your kernel at least.

OK, so here's the follow-up: since Thomas prodded me, and I have a weakness for unrestrained bouts of geekery anyway, I gave it one more try... and got some good results (didn't have much to do with configuring X, though. Sorry, pal.) I even got my framebuffer stuff working, including Tux at boot time - yay!

I installed the 2.6.0-test11 kernel so I could do the "swsusp" patch - haven't yet, the network here at the hotel died for an hour or so and just came back up - and compiled it (I think this is where the framebuffer stuff came from; I hadn't changed anything in that section.) Previously, though, I got a very thin lead from a discussion I saw where somebody recommended turning off AGP in the kernel config, since the ATI driver does its own, followed by someone else recommending trying it both ways - according to them, some ATI cards will only work with ATI's AGP while some others work only with in-kernel AGP. Actually, that didn't help anything, but while twiddling this, and making corresponding tweaks in the ATI "fglrx" driver configuration, I got an error from trying to load "fglrx" - 'The fglrx module must be loaded before any other DRM driver!' From there, it was a short trip back to the kernel, compiling the ATI Radeon DRM as a _module,_ then loading "fglrx" followed by "radeon" in /etc/modules, and - /voila/! Well, partially.

I now have 1280x800 video with 24 bit color (still not fantastic as compared to what the card/screen can do, but certainly better.) According to the messages in the X log, this is the best that the ATI driver can do - which is pretty sad, but what can you do. Hopefully, they'll make it better as time goes on.

"swsusp" and the card reader are next on the list...

(For those of you who think I'm blowing my time in Hawaii on this stuff, wrong. I'm getting up at 4:30 a.m. local time - which is 9:30 a.m. by my internal clock, which I'm lucky enough to have decent control over - and banging away on this until it's time to go to work. Ooops - it's that time now!)

[Thomas] Odd. Did you:

cp /boot/config-$(uname -r) /usr/src/linux/.config

before you compiled the kernel?

If you try doing this from 2.4.X -> 2.6.X it will not work. In any case, I always like to build kernels using a fresh config file no matter what I last used.

[Ben] Not at all. My first experience with the 2.6 kernel was this past week, and I was greatly tickled by the fact that it automatically takes the previous .config and (obviously) does a bit of intelligent parsing. You can even (and this is what I did) do

make oldconfig

after installing the new kernel, and it will load up the old config file and only ask you about the differences (there weren't any between 2.6.0 and 2.6.0-test11.)

Well, at this point, I've managed to take a largish step back. :/ "swsusp" docs say that you should have at least $MEMSIZE * 1.3 in swap, so I blew off the empty partition that I had following swap, deleted both of them, resized swap and created a partition out of what remained... and now, when I boot, "fsck" falls down with a loud "THUD" and cries that it found an error and I should re-run it as root without "-a" or "-p". When I do so, it tells me I have a mismatch between what the BIOS and the partition info say (about 2,000 sectors) and requires me to press 'Enter' 6,000 times (it generates 3 error messages/prompts per sector.) No, you cannot pipe the output of 'yes' to it. Laying a weight on the 'Enter' key (hi-tech solutions is us!) gets it done in about five minutes... after which it proceeds to repeat exactly what it did before. However, in this case, "Hit Ctrl-D to continue normal startup" actually does work, so here I am. [sigh]

[Thomas] Hmm, did you use cfdisk for this? It might be that you have to have a new map file in your /boot partition. Try running lilo again to see if that'll kick it? It might be worth just disabling swap for the time being and manually running:

swapon /dev/xxx

later on.

I used cfdisk. Deleted them both, made two new ones using the space. However, it's fixed already. Deleted them again, rebooted with them still as free space (that way I knew that "fsck" couldn't complain about partition mismatches there), then recreated them on the next boot. Whew.

[Robos] There have been sone synaptic touchpad fixes gone into 2.6.1 according to changelog.

[Ben] Not enough of them - tapping the touchpad, which has always worked, got borked in the process, and "gpm" doesn't work with the "synaptic" driver in the kernel (TONS of spurious messages.) Fortunately, I found patches for both of them. Tapping still doesn't work in the console, but it's not a huge issue. Also, the touchpad buttons are arranged like this:

   	  _______________________
	 |                       |
	 |                       |
	 |                       |
	 |        Touchpad       |
	 |                       |
	 |                       |
	 |                       |
	 |                       |
          -----------------------
	 |          _|_          |
	 |         /   \         |
	 | Button |  X  | Button |
	 |   1     \___/    2    |
	 |           |           |
	  -----------------------

where 'X' is the four-directional 'scroll' button... which makes it damn near impossible to click 1+2 to paste. There's yet another patch that allows 'up' on the scroll button to be used as button 3, but I haven't managed to make it work yet.

Other than that, I'm actually doing reasonably OK with it for the amount of time I've spent tweaking it:

Working:
1024x768 video
Sound
Touchpad (except the above issues)
NIC
USB2.0
ACPI (no suspend yet, though)

Untested but everything loads OK:
Wireless networking
Bluetooth interface
CD-RW/DVD-RW
Firewire
Parallel port
Video out
FIR

Not working yet:
4-in-1 card reader
Better video
Framebuffer
Modem (Lucent winmodem, bleh :( There's probably a binary driver
       somewhere, but I think I'll get a PCMCIA modem.)
Five-way "media control" keys

[K.-H] Dell Inspirons (and maybe others) had 1600x1200/15" for some years now at least starting with the Insp. 8000 on which I'm typing. There were Insp. 5000 with high res 15" screens as well. The current 8600 or higher have an even higher resolution on the top models. As you sit rather close to a lapscreen I like the display. I had to switch some fonts to a slightly larger one, but the displays are very sharp at the native resolution and a 10pt full A4 page in gv (antialias on) is quite readable.

Currently I'm thinking about a desk TFT -- and am rather unimpressed as you almost can't get more then 1024x768 up to 17", then 19" have 1280xWhatever. Admittedly that screen is further back from the keyboard, but why is no company offering any TFT with a higher res. They are possible after all.

The Inspirons use either nvidia Geforce 2 (or up in later models) or ATI Cards -- which won't help you Ben. I hope you figure out how to get into native resolution. For most others XFree4 seems to calculate good modelines by itself (I've not specified any). As yours is slightly weird maybe you need to specify one, keep looking on google.

There are four partitions on the new machine's HD: Wind0ws C:, Wind0ws D:, "suspend", and... ready for this?... Linux. I kid you not. This gadget has what's called "EFI", which I just happened to read about the day before I bought it by pure coincidence (I had no idea that this machine would have it) - it's a BIOS "replacement" that allows much easier pre-boot programming. What these folks have done, clever buggers that they are, is create an app - two of them, really - called "Arcade" (plays VCDs/DVDs, shows your picture repositories, etc. - sound familiar? Think "MoviX", etc.) and put a button on the front of the laptop. When the 'top is _off,_ pushing this button fires up "Arcade" without starting Wind0ws. When it's on, it fires up a Wind0ws app that looks exactly the same. Is this cool, or what? The way I found out that it was Linux is by running LNX-BBC and looking at the partitions. When I saw "/bin", "/boot", "/etc" and so on, I thought I was having a brain cramp... took me a bit to figure it out.

[Jason] Okay, so there is actually some version of Linux installed on the laptop? That is really interesting. If you have time (Ha ha!), I'd really like it if you could post some details sometime.

I don't have the HD installed (although I have it with me), but what I remember of it is this: it's a minimal (sorta like a "chroot" jail) system with a large tarball in "/". Looking inside the tarball revealed a more complete system; presumably, it works something like the LNX-BBC system (Oy, Heather!) by using the basic system to fire up, then decompress the tarball into memory and "pivot_root" (I'm guessing here.)

[Jason] BTW, when I first heard about EFI, my first thought was "Cool!". My second thought was "Somebody is going to code up a Tetris clone for this thing". Really, what could be more fun than playing tetris without having to boot up an OS? Actually, I expect people to more or less treat it like another OS, because, AFAIK, that's basically what it is. So expect all manner of useless programs.

I've explored it a little further, and it seems to be some Chinese-assembled version of Linux; fires up, opens up a tar archive, chroots into it, and runs a rather flashy Linux app (a front-end for lots of neat-o music/DVD/CD/etc. utils - mostly based on "mplayer", AFAICT.)

[Robos] Well, you should then write the mplayer folks a nice email telling them that. Quite recently they even started a new ml called mplayer-legal... Or do you think you can get the sources somewhere?

[Ben] It's quite cute, with a bunch of "lilo.conf.X" entries in /etc - obviously in case the partition ends up being anything other than hda4 which is where it is by default. Cuter yet, there's no alternate VT you can flip to - but there is a getty running on a serial port, and "/etc/passwd" doesn't have an entry for "root" but does contain one for "ava:0:0:..." Ain't that preeeecious?

Heck, I might just copy the thing and put in on a CD for a stand-alone movie/slideshow/etc. player.

I've actually considered doing that [a howto], on the principle that if I had that much trouble, other people surely will as well. However, I've held off so far because I'm not quite finished yet; I've zapped the original HD back into the Acer, and am now trying to split hda1 into hda1 and hda5, for Wind*ws on 1 (10GB or so) and Linux on 5 (40GB). However, the DVD+R media that I bought for backing up hda1 turns out to be incompatible with the drive (which does only DVD-R and down), so I have to go back to the store.... all this in between yoga classes, a flight medical (I now have my class III flying license), actual flying, chanty singing with a reenactment group, trying to somehow get Net access going (I've sorta got it - by buying a new cellphone), patching a leak that my dinghy has mysteriously developed, dealing with a couple of clients who have picked this time to play some highly shitful games with paying me (until I threatened legal action), fixing a recalcitrant propane heater in my aft cabin, and handling the initial stages of what looks like a local romantic involvement.

Lightweight, (Almost) Crypto-Free Remote System Operation

By Ray Ingles

"There are two ways of constructing a software design. One way is to make it so simple that there are obviously no deficiencies, and the other is to make it so complicated that there are no obvious deficiencies." - C.A.R. Hoare

"Sure I'm paranoid, but am I paranoid ENOUGH?" - Unknown

Introduction

System administrators frequently want to be able to work on the machines they run even when they are far away from them. There are secure tools that allow full remote shell access, like ssh and lsh, but due to their complexity they have suffered critical exploits from time to time. In addition, their overhead can be excessive for some purposes. Fortunately, other options are available that can be used alone or can be combined with remote shells to create a more secure overall system.

Overview

Maybe the pager has just gone off when you're home in bed, and the boss wants you to fix the broken database now. Or perhaps you're out for lunch and someone calls to tell you the mailserver has been cracked and is currently spamming the world, and you need to bring it down fast. Possibly you've checked and your Web server has wedged itself and needs to be restarted. Or suppose you're just on vacation and find you want to update your home Web site with some new photos. In all these cases, you'd like to do something to the machine over the Internet without having to actually sit in front of it - things you don't want just anybody t