Setting the device up to work with Debian Etch is fairly straightforward once you know what to do

Obviously, you need a motherboard with built-in Bluetooth or a USB Bluetooth receiver. Once you have that, lets install the software you’ll need:

apt-get install bluez-utils bluez-gnome

Now we need to figure out the Bluetooth address of the keyboard:

user@host:~$ hcitool scan
Scanning ...
        00:23:41:D4:42:78       laptop
        00:27:E2:A1:3F:E5       Apple Wireless Keyboard

Now that you have the Bluetooth address of the keyboard, lets modify the following lines in /etc/default/bluetooth:

HIDD_ENABLED=1
HIDD_OPTIONS="--master --connect $(bluetooth addr) --server"

Next you’ll add a new section to /etc/bluetooth/hcid.conf for the keyboard:

device $(bluetooth addr) {
    name "Apple Wireless Keyboard";
    auth enable;
    encrypt enable;
}

At this point you can pair the keyboard. Since I use fluxbox on my MythTV frontend computers I manually start the required applets, etc.

1. Start window manager
2. As the logged in user, run “bluetooth-applet”
3. Power cycle the Bluetooth keyboard
4. As root, execute “hidd –connect $(keyboard addr)
5. Type a PIN number on bluetooth keyboard (i.e. 1234) then hit return
6. The bluetooth applet will start flashing in the window manager.
7. Click the bluetooth applet and enter the same PIN in the dialog that pops up

That should be it. You now have a working wireless keyboard :-)

If anyone knows of a way to do this entirely on the command line, bypassing the window manager and bluetooth-applet entirely, I’d love to hear it.

Enjoy!

Our test system, for those who dont follow this blog regularly, is a Supermicro X7DVL-E motherboard with a single Intel Core2 Xeon 5130 @ 2Ghz with 2GB of RAM. The disks used are Seagate ES.2 1TB SATA-II models hooked up to two Supermicro AOC-SAT2-MV8 8-port PCI-X SATA controllers. More complete specs are outlined in my original post where I was building the chassis, which can be found here.

The Linux distribution used is, of course, Debian :-) In this case, its Debian 5.0 (Lenny) running kernel 2.6.26-1-686.

Test #1 – Individual Disks
In order to get some baseline numbers to compare against subsequent tests we will first check performance of all the attached disks individually…
for disk in $(ls /dev/disk/by-id/ | grep -v part | grep scsi-SATA_ST); do
echo $disk && \
dd if=/dev/zero of=/dev/disk/by-id/$disk bs=4M oflag=direct count=250 && \
dd if=/dev/disk/by-id/$disk of=/dev/null bs=4M count=250;
done

Which yielded these results…

5QJ06913 - read:109MB/s, write:109MB/s
5QJ09HZR - read:111MB/s, write:112MB/s
5QJ09JHQ - read:113MB/s, write:109MB/s
5QJ09JV3 - read:109MB/s, write:108MB/s


So our average raw device read speed is 110.5MB/s and writes are 109.5MB/s.

Test #2 – Bonnie++ on a single disk
Next we will do a bonnie++ test on a single disk (5QJ06913), formatted with default ext3 options

mkfs.ext3 /dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ06913
mount /dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ06913 /mnt
/usr/sbin/bonnie++ -q -d /mnt -s 4096 -x 5 -u root

This test produced average block reads of 105.55MB/s @ 11.4% CPU usage, block writes of 65.93MB/s @ 19%, and block rewrites of 36.95MB/s @ 8%.

Test #3 – RAID1 pair
For this test we use a RAID1 pair with one disk on each controller, formatted with default ext3 options

mdadm --create /dev/md2 --level=1 --raid-devices=2 /dev/sdf /dev/sdg
dd if=/dev/zero of=/dev/md2 bs=4M oflag=direct count=250
dd if=/dev/md2 of=/dev/null bs=4M count=250


This produced raw I/O reads of 111MB/s and writes of 107MB/s. Now for some bonnie++ tests…


mkfs.ext3 /dev/md2
mount /dev/md2 /mnt
/usr/sbin/bonnie++ -q -d /mnt -s 4096 -x 5 -u root


This test produced average block reads of 103.43MB/s @ 14.4% CPU usage, block writes of 60.84MB/s @ 18.6%, and block rewrites of 33.82MB/s @ 8.8%.

Test #4 – RAID10
For this test we use a RAID10 device consisting of two RAID1 devices, each with a disk on each controller.


mdadm --create /dev/md4 --level=0 --raid-devices=2 /dev/md2 /dev/md3
dd if=/dev/zero of=/dev/md4 bs=4M oflag=direct count=250
dd if=/dev/md4 of=/dev/null bs=4M


This produced raw I/O reads of 219MB/s and writes of 207MB/s. A pretty significant improvement.


mkfs.ext3 /dev/md4
mount /dev/md4 /mnt
/usr/sbin/bonnie++ -q -d /mnt -s 4096 -x 5 -u root


This test produced average block reads of 198.91MB/s @ 27.8% CPU usage, block writes of 132.4MB/s @ 44%, and block rewrites of 61.75MB/s @ 14.4%.

Test #5 – RAID5
For this test we will use a RAID5 device with the first two disks on one controller and the third on the second controller


mdadm --create /dev/md2 --level=5 --raid-devices=3 /dev/sdf1 /dev/sde1 /dev/sdg1
dd if=/dev/zero of=/dev/md2 bs=4M oflag=direct count=250
dd if=/dev/md2 of=/dev/null bs=4M


This produced raw I/O reads of 67.3MB/s and writes of 130MB/s.


mkfs.ext3 /dev/md2
mount /dev/md2 /mnt
/usr/sbin/bonnie++ -q -d /mnt -s 4096 -x 5 -u root


This test produced average block reads of 62.91MB/s @ 8.6% CPU usage, block writes of 65.73MB/s @ 19.6%, and block rewrites of 33.14MB/s @ 7.6%.

Those were all the RAID types I was inclined to test. I realize I left out RAID0 and RAID6. For the application I have in mind, RAID10 is the clear winner. You can download a spreadsheet with the actual bonnie++ output here. Enjoy!

First of all, install open-iscsi
dpkg -i open-iscsi_2.0.869.2-2_i386.deb

Now compile and install iscsi-target
tar -xzvf iscsitarget-0.4.16.tar.gz
cd iscsitarget-0.4.16
make
make install

And now the important bits. iscsi-target needs to be added to the sysv init scripts in the correct places, which a source install obviously doesnt do:
update-rc.d iscsi-target start 44 S . stop 82 0 6 .

That will make it start just before open-iscsi and stop just after it. Thats it! Any iscsi target that you configure with with the “automatic” option should be correctly connected to during bootup
iscsiadm -m node -T iqn.2008-01.net.pixelchaos:mytarget –op update -n node.conn[0].startup -v automatic

In keeping with my character, the first thing I did was start all over again from scratch by reinstalling the operating system. This time around I set up /dev/md0 as /boot (255 MB) and /dev/md1 as an LVM physical volume (the remainder of the disk), within which /, /home, /usr and friends reside as logical volumes. Its something I’ve wanted to start doing with all my systems for a long time now and shouldn’t have any bearing on the performance tests we are about to do.

Regardless of which protocol will be used we need to enable jumbo frames on all the involved devices. For my setup that means the target (stor01), the initiator (node02), and the switch (a Cisco Catalyst 2970).

First, we turn on jumbo frames for gigabit ethernet at the switch. Beware that this requires a reset (aka reboot) of the switch to take effect:


c2970# system mtu jumbo 9000


Now we enable an MTU of 9000 on both the target and the initiator:


root@stor01:~# ifconfig bond0 mtu 9000



root@node02:~# ifconfig eth0 mtu 9000


For the sake of comparison, here is an iperf test done between the target and initiator with the standard MTU of 1500, and then with an MTU of 9000:


root@stor01:~# iperf -s
------------------------------------------------------------
Server listening on TCP port 5001
TCP window size: 1.00 MByte (default)
------------------------------------------------------------
[ 4] local 65.171.150.4 port 5001 connected with 65.171.150.161 port 58731
[ 4] 0.0-10.0 sec 780 MBytes 654 Mbits/sec
[ 5] local 65.171.150.4 port 5001 connected with 65.171.150.161 port 58732
[ 5] 0.0-10.0 sec 916 MBytes 768 Mbits/sec


As you can see, just enabling jumbo frames produces a raw throughput increase of 17.43%. Nothing to sneeze at.

At this point I tried enabling flow control on the catalyst switch (it is already enabled for both send and receive by default in the e1000 driver) but it did not have any effect on iperf numbers. I turned it back off for now.

So now we set up a 20GB LVM volume on the target and export it using vblade to be mounted on the initiator. We then run a simple dd test to check throughput:


root@node02:~# dd if=/dev/zero of=/mnt/test oflag=direct bs=4M
419+0 records in
419+0 records out
1757413376 bytes (1.8 GB) copied, 133.476 seconds, 13.2 MB/s


CPU load on the target was 10-15% during the dd operation. Now we try writing direct to the (unmounted) block device to rule out any performance penalties of the filesystem itself…


root@node02:~# dd if=/dev/zero of=/dev/etherd/e0.1 oflag=direct bs=4M
513+0 records in
512+0 records out
2147483648 bytes (2.1 GB) copied, 170.991 seconds, 12.6 MB/s


CPU usage was slightly higher in that test, running 15-20%. So some slight difference but nothing to be too concerned about.

Now we take that same LVM device and share it via iSCSI for the same dd tests:


ladmin@node02:~$ dd if=/dev/zero of=/mnt/test oflag=direct bs=4M
462+0 records in
461+0 records out
1933574144 bytes (1.9 GB) copied, 38.2375 seconds, 50.6 MB/s


CPU load was 6-8% during that test. We also run that same test with flow control enabled at the switch:


ladmin@node02:~$ dd if=/dev/zero of=/mnt/test oflag=direct bs=4M
463+0 records in
462+0 records out
1937768448 bytes (1.9 GB) copied, 38.1851 seconds, 50.7 MB/s


Essentially the same…

Now this raises the question of why AoE is so much slower than iSCSI on an essentially default install of Debian Etch. To AoE’s credit, many people report getting just as good (50MB/s or better) of performance from AoE on their systems as I’m seeing with iSCSI. I spent quite a large amount of time playing with flow control, kernel ring buffer values, filesystem options, etc. and was unable to determine why performance is so terrible for me. I did find a pretty high number (half a dozen at least) of recent posts to the AoE mailing list by other people having essentially identical problems so I’m certainly not alone. In the interest of completing my testing, I’ve decided to move forward with iSCSI.

Now we try reformatting with the stride option to mkfs:


mkfs.ext3 -E stride=16


The results of several more tests are shown here…


root@node02:~# dd if=/dev/zero of=/mnt/test oflag=direct bs=4M
2038431744 bytes (2.0 GB) copied, 41.8938 seconds, 48.7 MB/s
2038431744 bytes (2.0 GB) copied, 42.2633 seconds, 48.2 MB/s
2038431744 bytes (2.0 GB) copied, 41.3756 seconds, 49.3 MB/s


So we don’t see any appreciable difference when using a combination of the stride= option and flow control, at least with a simple dd test.

Next we turn flow control back off, and reformat again without the stride= option. We are now back to our baseline setup for a new test with bonnie++.


ladmin@node02:~$ /usr/sbin/bonnie++ -d /mnt -s 4096Mb -n 10 -x 5 -q


This test produced block writes of about 82MB/s and block reads of about 37MB/s. The cause for the difference in write speed between the dd and bonnie++ tests is still unclear to me. There also appears to be a known issue where writes are much faster than reads which is apparently due to interrupt handling. This is further evidenced by running a quick dd test that does a read instead of a write:


ladmin@node02:~$ dd if=/mnt/test of=/dev/null bs=4M
3602907136 bytes (3.6 GB) copied, 96.2053 seconds, 37.5 MB/s
3602907136 bytes (3.6 GB) copied, 90.5524 seconds, 39.8 MB/s
3602907136 bytes (3.6 GB) copied, 90.0425 seconds, 40.0 MB/s
3602907136 bytes (3.6 GB) copied, 88.5708 seconds, 40.7 MB/s


As you can see, read operations are about 20% slower than write operations which goes against common thinking with regard to stripped disk arrays.

So there you have it. In my particular situation, with no tuning/optimizing done, iSCSI performs much better than AoE. Even in the event that I were to go to the trouble to performance tune AoE and get it as good as, or even better than, iSCSI I would still be inclined to standardize around iSCSI. Authentication, routing, NAT, etc. can all be done very easily on iSCSI protocol with all the standard TCP/IP tools that are out there. For me that’s a pretty big advantage.

Next up will be our final piece of the puzzle, left over from the initial system setup – getting hot swap working with the sata_mv module!

The Debian Etch installer supports building and installing onto software RAID arrays. Because of that…

during installation I configured the initial RAID1 boot volume with hot spare, consisting of three WD 160GB SATA 3Gbps disks. mdadm sees / and swap as /dev/md0 and /dev/md1 respectively. There was some remaining space on the drives which I set up as /dev/md2 for future use. The remaining arrays I decided to create manually using mdadm after getting a usable system up and running.

First of all we need figure out what devices we want in the arrays by probing /dev. The ultimate goal here is to build three arrays: 1 x RAID1 with 1 hot spare (8GB root, 1GB swap, 151GB extra), 1 x RAID6 with 1 hot spare (4TB Xen LVM’s + 2TB Bacula LVM), 1 x RAID5 (2TB offsite mirror).

I was forward thinking enough to label all the drive carriers with the serial number of the disk in it so all we need to do is get the disk-by-id name from /dev/disk/by-id/ and then build our test array like so:


mdadm --create /dev/md3 --level=6 --raid-devices=8 \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ09HZR \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ09JV3 \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ06913 \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ08XHB \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ09KNM \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ09JHQ \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ0817T \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ09B9P \
--spare-devices=1 \
/dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ07CF3


This assembles our /dev/md3 device with the default options for RAID6 (64k chunk, left-symmetric parity)


stor01:~# cat /proc/mdstat
Personalities : [raid1] [raid6] [raid5] [raid4]
md3 : active raid6 sdl[8](S) sdk[7] sdj[6] sdf[5] sdh[4] sdg[3] sdi[2] sde[1] sdd[0]
5860574976 blocks level 6, 64k chunk, algorithm 2 [8/8] [UUUUUUUU]
[>....................] resync = 0.8% (8790864/976762496) finish=217.3min speed=74238K/sec


Here you can see that CPU load is moderate doing the first full sync of that array:


Cpu0 : 0.0%us, 33.3%sy, 0.0%ni, 63.3%id, 0.0%wa, 1.3%hi, 2.0%si, 0.0%st
Cpu1 : 0.0%us, 7.0%sy, 0.0%ni, 91.0%id, 0.0%wa, 0.3%hi, 1.7%si, 0.0%st


So, we wait about 4 hours… and its done :-)

For formatting the volume, I decided to use the stride= option to mkfs.ext3. This provides for optimal striping across a raid array. The secret here is to make $stride = $chunks / $block_size. In our case, thats 4096 byte (4k) blocks divided by 64k chunks. So 16 would be our optimal stride value.


root@stor01:~# mkfs.ext3 -E stride=16 /dev/md3


So how does it perform? Well enough to saturate the dual gigabit NIC ports – which is all that matters :-)


root@stor01:~# dd bs=4M if=/dev/zero of=/dev/md3
4469+0 records in
4469+0 records out
18744344576 bytes (19 GB) copied, 97.583 seconds, 192 MB/s


I also ran a more real-world test with bonnie++


/usr/sbin/bonnie++ -d /mnt -s 4096Mb -n 100 -x 10 -q


This test showed approximately 335MB/s read, 170MB/s write. You can download the actual data here if you wish.

For failure testing the array, its as simple as removing and inserting disks while the array is up and running. Both tests work fine for the onboard SATA II controller but alas, the sata_mv kernel module does not yet support hotplug so all we can do on the remaining drives is simulate a drive failure by removing one disk. This does work fine but I need to see if there is a way to refresh the SATA bus to get any replacement drive to show up and be added back into the running array. Otherwise, we will need to power down the array to replace a faulty disk which kind of ruins the whole project, dont you think? ;-)

So while we wait for sata_mv to start working (or find a different SATA controller to use in this project) we will move on to the remaining issues. Up next; getting port trunking working with a cisco switch…

First of all, hotplug. I have discovered that…

hotplug doesn’t seem to work on the Supermicro AOC-SAT2-MV8 cards. The controllers do work, but unless a drive is plugged in during bootup they will not be subsequently detected…


root@stor01:~# lspci
05:01.0 SCSI storage controller: Marvell Technology Group Ltd. MV88SX6081 8-port SATA II PCI-X Controller (rev 09)
05:02.0 SCSI storage controller: Marvell Technology Group Ltd. MV88SX6081 8-port SATA II PCI-X Controller (rev 09)


You can see that the Linux kernel sees these cards as Marvell MV88SX6081 devices. Further probing reveals that the sata_mv driver is claiming them:


root@stor01:~$ dmesg | grep 05:01.0
sata_mv 0000:05:01.0: version 0.7
ACPI: PCI Interrupt 0000:05:01.0[A] -> GSI 24 (level, low) -> IRQ 233
sata_mv 0000:05:01.0: 32 slots 8 ports SCSI mode IRQ via INTx


So off we go lkml.org and other sources to find out why… Basically, hotplug support in the sata_mv module is still a work in progress. A post to the lkml claims that its slated for inclusion in the 2.6.26 kernel. There is also more information here.

So hotplug isnt going to work for us today :-( On the bright side, 2.6.25-rc7 is the current development kernel so I can’t imagine that 2.6.26 is too far off.

The second (perceived) issue of getting all the hot swap bays to be mapped to /dev/sd* entries in a particular order doesnt seem to be as much of an issue as I’d thought.

The Linux kernel will initialize PCI devices in a strange fashion depending on what is plugged in to the bus. For example, if all fifteen bays have drives plugged into them, the leftmost bay always shows up at /dev/sda. Unplug just one drive and reboot the machine and it will be mapped to /dev/sdl for example. The reason this isnt really an issue is that newer Linux kernels have not only udev (which is great but not really a solution for this particular problem) but the /dev/disk/by-* tree. You can find all your disks in there with handy names like /dev/disk/by-id/scsi-SATA_ST31000340NS_5QJ06913. That name belongs to that particular drive and only that particular drive, ever.


root@stor01:~# ls -l /dev/disk/by-id/ | grep scsi | grep -v part
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ06913 -> ../../sde
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ07CF3 -> ../../sdi
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ0817T -> ../../sdb
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ08T21 -> ../../sdh
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ08XHB -> ../../sdc
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ09B9P -> ../../sda
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ09GMW -> ../../sdd
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ09HZR -> ../../sdg
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ09JHQ -> ../../sdk
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ09JV3 -> ../../sdj
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ09KNM -> ../../sdl
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_ST31000340NS_5QJ09LLA -> ../../sdf
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_WDC_WD1600AAJS-_WD-WCAP93952468 -> ../../sdm
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_WDC_WD1600AAJS-_WD-WMAS20341446 -> ../../sdo
lrwxrwxrwx 1 root root 9 2008-04-01 11:15 scsi-SATA_WDC_WD1600AAJS-_WD-WMAS20366839 -> ../../sdn


Cool, huh?

So we will just let mdadm do its job of assembling /dev/md* devices on the fly at bootup and use the /dev/disk/by-id entries to do stuff to particular disks (like temperature monitoring, etc.).

Coming up in my next post – performance and failure testing the array.

There happens to be a company (Coraid) that makes a turnkey AoE device. Its far cheaper than a true fibre channel SAN or something similar. Perfect for setting up a SAN over Ethernet device that can serve Xen domU filesystems out to “thin” dom0’s on the network.

Well that’s all well and good but you see I’m always looking to save a buck…

So I asked myself; why not build my own “coraid” with off the shelf parts and save 50% in the process? Herein I’ll do my best to chronicle my adventures in getting this thing built, tested, and (hopefully) deployed.

First of all the hardware. Thanks to the ever-brilliant Mike Neir for helping me figure out what Coraid uses to build these suckers. Here are the parts I ended up ordering:

• 2 x Supermicro 8-Port SATA Card (AOC-SAT2-MV8)
• 1 x Supermicro Xeon Dual-Core Blackford VS ServerBoard (X7DVL-E)
• 1 x Supermicro Black 3U Rackmount Case 760W (SC933T-R760B)
• 1 x Kingston 2GB 240-Pin DDR2 FB-DIMM ECC (KVR667D2D8F5K2/2G)
• 1 x Intel Xeon 5130 Woodcrest 2.0GHz 4M (BX805565130A)
• 15 x Seagate Barracuda ES.2 1TB (ST31000340NS)
• 3 x Supermicro Drive Carrier (CSE-PT39B)
• 3 x Western Digital 7K 8M SATA2 160GB (WD1600AAJS)

Now you may ask, why buy 18 drives for a chassis that has 15 hot swap bays? Well, I’ll be using the three WD drives as a RAID1 boot device with one hot spare, then setting nine of the 1TB drives up into a RAID6 device with one hot spare. The remaining three drives will be in RAID5 and swapped with the last three drives on a regular basis to go off site as part of a hard disk based backup system.

Now that we have all of that out of the way; how did the assembly go? Flawless almost ;-)

There are two gotcha’s to be dealt with in the assembly of the aforementioned motherboard and server chassis; first of all, the EPS12V connector for CPU power that comes out of the power distribution block wont reach its molex connector on the motherboard. Second, the ribbon cable that connects the front panel controls to the their motherboard header just *barely* reaches which makes me uncomfortable.

To resolve the first problem I ordered up a StarTech 8″ EPS 8 Pin Power Extension Cable (EPS8EXT) which did the job nicely. To fix the second issue, I ordered twenty feet of 16 conductor ribbon cable (might need extra!), some cable ends and a crimper. Problem solved.

With all that taken care of its time to get an operating system installed and test this thing out. I did go ahead and power up the system and test the redundant PSU’s and fans. The alarm features of both seem to work fine with audible alarms when any of them are removed from the system. After that I plugged an old CD-ROM into the ATA header on the mobo and installed a rockin Linux distro.

Some things I discovered:

• The BIOS and the Linux kernel both initialize the two SATA PCI cards first. Some fiddling will need to be done to make the three WD drives (plugged into the motherboard SATA headers) show up as sda, sdb, and sdc.
• You must turn off “compatibility mode” in the BIOS for the onboard SATA controllers or hotplug will not work for drives on those headers. After turning it off, hotplug works just dandy. Yay!
• Hotplug isnt working for the two PCI SATA cards at this point. I suspect its something to do with the sata_mv kernel module but havent gotten to look into it much. That will be the first order of business when next I work on this project.

So thats it for now. Things are coming together nicely. My next post will detail getting hotplug working for the two PCI SATA cards and getting device detection and mapping working correctly in the Linux kernel (I smell some udev tomfoolery most likely).

Now that the noisy GPU cooling fan is gone (yay!) I’ve begun to notice the noise that my dual SATA hard drives generate. I got sufficiently motivated last night to figure out a way to silence them. What I came up with was a “hard drive suspension mechanism” of sorts that cost, oh, probably about $0.13. Best of all, the drives generate ZERO noise from vibration now.

Click here to see some pics. My wife’s laptop is now actually louder than my dual core workstation :-)