Resurrecting old hardware...

Hardware is getting faster and faster, so people upgrade as the needs get bigger and bigger. What about the old hardware that stays behind? Some of it gets reused for low priority servers but most of them get thrown away as obsolete. The worst case is if the hardware itself has become obsolete aka its maxed out when it was current.

Well I happened to be involved in one of this type of resurrections. The server was an IBM xSeries 220 tower with 72GB hardware raid 1 array and a small 40GB IDE drive. The idea was to upgrade the small IDE to a 160GB drive to get more storage area. As the 220 has show insane stability the idea was well at the beginning, well until the new drive was installed and well, the Linux recognized it. But here is where the problems started. The performance was insane - the drive would max out at 500KB/s with the read timings test (hdparm -t /dev/hda). The other symptom was drive seek errors which would indicate that there were bad blocks at the beginning or supernodes which would mean that the drive was dieing.

As the Maxtor's drive was brand new (just out of the anti static bag) it could not be the case. After a test with a second 160GB drive the results were the same. Logically thinking - this means we have hit the LBA32 127GB limit. The BIOS cant address more address space than 127GB and when you do you hit the brick wall of buffer overflows in the address registers (most likely when you write over 127GB you start from the 0x0 h again and write up the drives beginning). Of course the Linux kernel takes over the drive addressing after you boot up, but for that to work well the BIOS has to be satisfied first. Well copying 127GB at the rate of 500KB/s would take 266 338 seconds - thats around 3 days straight - I didn't have that much time to wait to see what would happen after the limit gets exceeded.

So what to do when your hardware is too obsolete for upgrading to your needs? You hack it!

In my case it was simple as Maxtor has firmware utility called SeaTools that can change the drive capacity in the firmware. Why is that good you ask? Well this way we can fake the hardwares without using the soldering iron or assembler to hack the firmware in the device.

The procedure goes like this:

1. install the new HDD
   
2. boot into BIOS and accept the changes (new HDD 6GB?!?!?)
3. boot into the SeaTools utility (CD or floppy)
4. Change the drives capacity to be 32GB
5. Shutdown the machine and remove the drive
6. Boot into the BIOS and accept the changes (the IDE drive has gone away)
7. Shutdown the machine and reconnect the drive
8. Boot into BIOS and accept the changes (new 32GB drive)
9. Boot into the SeaTools and restore the drives capacity
10. Boot into Linux :)

The BIOS still thinks it has a 6GB drive connected but its happy with it. Also the Linux boots up faster as BIOS is not complaining about seek errors when addressing the drive.

Running hdparm  -t should result in 13...25MB/sec - not the best speed but a lot better than 500KB/sec. You may ask what the range is so big - but I don't have an answer. On some systems the drive runs with udma2 mode on others in mdma2 mode. Forcing the mdma2 mode to go to udma2 mode did not seem to have the desired performance change but still its working well enough.

Many may ask "why would you ever want to resurrect an old xSeries 220", but the answer is simple. The system has been in use for a long time and if it has not died so far it wont in the near future. Also the speed is boosted with built in SCSI drives.

So where to use the old xSeries 220? Well, for test servers, for low priority web/sql servers, dns servers - there is no good answer. It all depends on the needs of the system. One place would be central log server - aka other servers log to this host, the syslog would save the logs in real time to the SCSI drives and nightly you rotate the logs to go into the mysql database on the IDE drive. Why do this? Well, logs are here for one purpose to be analyzed afterwards.

Another good example would be to use it as a file server - share out the data on SCI to Linux hosts and from IDE to windows hosts and if they start to complain that the speeds are soooo slooowwww blame it on windows and propagate the move to Linux :P

What can I say - use Your imagination.
Tested on CentOS 4.5 - but should work on any Linux with 2.6 kernel.

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Linux Bioapi on Fedora 7...

I have been using bioapi and pam_bioapi on my T43p ThinkPad under SuSE 10 Pro for the past 2 years and been happy with it. No annoying password prompts to type your passwords and well typing your password to the screen saver prompt... I wont go into that...

As always all good things have to end sometime, so went my bioapi when I replaced my SuSE with Fedora 7. The reason to switch to Fedora was forced upon me by the all famous evil MicroSoft with its all famous MSN version upgrade. As I hacked the Kopete as much I could the old libs in SuSE were not just up to the task of plain rebuild to a newer version.

After backing up the usuals about a week ago I reinstalled my laptop. No big deal. Around half an hour of installation, another half a hour to strip all of the gnome components and yum junk and another 2 hours of installing and configuration of KDE. All was well untill I remembered the most important thing - I didn't backup my own rpm's. And this included the bioapi and the pam module. After about 20 times entering the password for screen saver the old finger swiping reflex started to come back. Crap...

Oh well - I had to start from the beginning.

The first thing to do is the bioapi lib's. Everything is straight forward until I started packaging it. Google was no help - the best thing google could offer was the "--with-Qt-dir=no" configure option, but that was not acceptable for me. I needed the Qt for my screen saver so after little debugging I found the evil source of the Qt compile errors. It is an rpm macro

# here is a hack
# in /usr/lib/rpm/rpmrc line 18
# replace optflags: i386 -O2 -g -march=i386 -mcpu=i686
# with optflags: i386 -O2 -g -march=i386

Every time when compiling the configure test part spitted out error messages about mcpu being deprecated and the test failed.
As I'm low on time for the time being I just used the hack and Bingo - every test was passed successfully.
As this is literally an hack I wont be using it for other packages until needed again, but basically its biapi's testing problem and currently I don't have time to start fixing it. The i386 rpm is here and the source rpm is here. One day I will move the udev rules the the bioapi package, but not right now.

Ok, so everything should be set to run the bioapi right? Well, not really - the one thing that I had totally forgotten was the UPEK inc. tfmss bsp api. This was the most frustrating thing as I had forgotten about it totally. As it is distributed under property license and it seems everyone have drawn back their binary and source packages I'll just publish the spec to build the rpm and the config. It seems that UPEK is forcing their license, so here is the spec and here is the configuration fail. A simple rpmbuild will build the package that can be installed. For licensing read the SDK EULA, and thus I'm not responsible for whatever you do after building the package - this information is provided AS IS, without any warranty by the packager.

The final thing is the pam_bioapi package. This packaged nicely without any hiccups. But then the problems started. It seems that the new version of the module is only capable of using SQLlite3 back end and not the old flat bir file based back end (atl east I dint find an option to enable it). Thus I'm still without a working bioapi. Oh well - back to the old reliable 0.2.1 it went. After little patching it built nicely. But the problems did not end - I started to get bioapi errors. "BioAPI error #194d" - google did not give any good answer to it except it is a permissions error. After some debugging I found out that the error is cosed by wrong permissions on the usb fingerprint reader device. By default it is owned by root and writable by user root - naturally I'm not a root on everyday tasks so I did some magic and got it running. To make the changes permanent I wrote a little udev rule that makes the device to be owned by group "fingerprint" and made it writable by the group so it started to work nicely. Here is the rpm and here is the source rpm.

I also included a mini "howto" on how to get it to work fast and easy. I also may be missing some libs and deps from the packages as my systems are always bloated with libs and development headers, but the examples are here, so have fun everybody.

Some useful links allso: udev rule writing, file permissions in linux, a good howto on enabling fingerprint reader, the bioapi error I mentioned before, another error symptom, Novell way of doing things, the TFMSS fingerprint reader api.

Thats about it for today - have fun and play nice :)
PS! Great thanks the the people in UPEK for releasing the Linux port for the fingerprint reader api :)

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Uplink - The way of the hacker...

Ok, so this is a bit of off topic, but I just could not leave it unmentioned.

Everyone is talking that Linux is crap just because there are no games that run natively under Linux and I'm not talking about the GPL-d games and the community "hacked" games. All the big game companies are wining about the lack of standard game development api-s and libraries, but they exist and they just don't have the coders to port the games to Linux as they are only built on top of the windows DirectX api-s and are not written in consideration for other rendering api-s. So its simpler to blame the Linux for lacking api-s than admit that it would take around 3 years to totally rewrite an existing game to Linux.

Well, I'm glad that one small firm has written a game that runs natively under Linux. The game is called Uplink and the company is Introversion.

This game has existed for a while (ummm 4+ years) and as I have not played games for a while I found that it had a native Linux version built also :)

Ok, the game is not really big and fancy for its graphics, but starting from version 1.3 it looks like its windows counterpart. As I'm found of my 1600x1200 resolution the 1.3 version is the milestone that proves that it is doable. Maybe it is not as simple to make a 3d FPS than a 2d strategy/RPG but it just show that the potential is there and that the big companies should stop hiding behind the "lack of api-s" and start thinking of the market share the Linux games will be taking in the near future. Especially when the "Completely Fair Queue" has been implemented in the Linux kernel starting from 2.6.23.

As a side note - an old goddy also exist "Railroad Tycoon" run through OpenTT works also perfectly :)

PS!: I love my vacation so far :)

technorati tags:Linux, Hack, Gamei

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