dreadnought (Main workstation)

Motherboard didn't work out for mirage because AMD dropped support for older CPU in their A520 chipset. Ended up holding on to the board for what became dreadnought.

Started collecting parts with the intention of building a video capture machine. Something with reasonable power and relatively compact. Case size became compromised a bit to fit a full size BD drive I had for use with UHD discs.

Settled on a Ryzen 3 Pro 4350G because it is cheap, it has enough cores, and limited compatibility of the A520 with 2nd/3rd gen iGPU Ryzens. GPU prices were sky high from market conditions, and even finding the WX 2100 I wanted was prohibitive. It could be a bit more powerful machine, but this also frees up the PCIe slot for firewire or internal capture devices.

Build went off without a hitch. The case is a little cramped for cable routing, but I only had to sacrifice the drive area intake airflow path.

Internals - Top View

Internals - Side View

Rear IO

Internals - cabling, drives, pcie

Drives installed

Attempts at running four iSight cameras over firewire ran out of isochronous resources. I can get away with reduced resolution or framerate, but they're already pretty limited so I went for the dual FW643 firewire card from Point Grey (FWB-PCIE-02) that should handle 3 per port.

I had trouble with obs midi segfaulting. It seemed to be in the libremidi library, but I didn't look into the backtrace much. I grabbed their alpha release, and a different repo of libremidi. Aside from following the instructions in build.md under ## Linux; I manually cloned libremidi into src/libremidi, and I changed CMakeLists.txt as below.

@@ -88,6 +88,7 @@ add_library(obs-midi MODULE
        src/forms/settings-dialog.ui)
 include_directories(
        "${LIBOBS_INCLUDE_DIR}/../UI/obs-frontend-api"
+       ${LIBOBS_INCLUDE_DIR}
        ${obs_midi_UI_HEADERS}
        ${Qt5Core_INCLUDES}
        ${Qt5Widgets_INCLUDES}

I also had to modify libremidi's CMakeLists.txt as follows.

@@ -49,6 +49,7 @@ endif()

 target_compile_features(libremidi ${_public} cxx_std_17)

+find_package(Qt5 COMPONENTS Widgets)
 find_package(Threads)
 target_link_libraries(libremidi ${_public} ${CMAKE_THREAD_LIBS_INIT})

I did a fresh install of Debian 11 with manual partitioning, and encrypted root. The installer is frustrating in that if you set up an encrypted partition there is no way to delete it without restarting the installer.

I also installed gnome because I forgot gnome defaults to Wayland which isn't suitable for my use (barrier, possibly local obs screen capture). Gnome is also annoying because despite it's ability to rotate the screen it doesn't handle input device (touchscreen, stylus) rotation so you're left with broken inputs. If I'm going to have to manually configure everything anyway I decided I'm better off in Xfce with fully configurable panels and other things that aren't built to hide every conceivable power user feature away.

Xfce is disappointing after using i3 for a long time. I gave up.

dreadnought has a semi-remote usb hub, and I want it to boot without interaction unless but still be encrypted root. I figured putting a key on a usb stick in the remote hub is effective enough to prevent easy access if the dreadnought is removed from the premises.

Based on https://www.howtoforge.com/tutorial/passwordless-encryption-of-linux-root-partition/ and https://gist.github.com/da-n/4c77d09720f3e5989dd0f6de5fe3cbfb

1. Put random data on the usb stick It's not clear where these tutorials are producing the random data that is used as a key. Probably something they did during install that I skipped. I just overwrote my whole usb stick with /dev/random to start with. It is slow (~1-2 MB/s).

   dd if=/dev/random of=/dev/disk/by-id/usb-General_USB_Flash_Disk_0000000000000000-0\:0 status=progress
   

2. Save a copy of the key

   dd if=/dev/disk/by-id/usb-General_USB_Flash_Disk_0000000000000000-0\:0 of=/root/cryptsetup.key bs=512 skip=4 count=16
   

3. Add the key to a key slot (keep slot 0 for password). You need to enter the existing passphrase to add the new key.

   cryptsetup luksAddKey /dev/nvme0n1p2 /root/cryptsetup.key --key-slot 1
   

4. Add a udev rule to symlink and enumerate usb devices

   Listing 5: /etc/udev/rules.d/99-custom-usb.rules

   SUBSYSTEMS=="usb", DRIVERS=="usb",SYMLINK+="usbdevice%n"
   

   udevadm control --reload-rules
   

   Replug the device and check for those symlinks in /dev/usb

5. Add a script to read the key from the usb device

   Listing 6: /usr/local/sbin/openluksdevices.sh

   #!/bin/sh
   ############taken from following link#########
   ###http://www.oxygenimpaired.com/debian-lenny-luks-encrypted-root-hidden-usb-keyfile
   
   TRUE=0
   FALSE=1
   
   # flag tracking key-file availability
   OPENED=$FALSE
   
   if [ -b /dev/usbdevice ]; then
   # if device exists then output the keyfile from the usb key
   dd if=/dev/usbdevice bs=512 skip=4 count=16 | cat
   OPENED=$TRUE
   fi
   
   if [ $OPENED -ne $TRUE ]; then
   echo "FAILED to get USB key file ..." >&2
   /lib/cryptsetup/askpass "Try LUKS password: "
   else
   echo "Success loading key file for Root . Moving on." >&2
   fi
   
   sleep 2
   

   Make it executable:

   chmod a+x /usr/local/sbin/openluksdevices.sh
   

6. Add the keyscript to crypttab

   Get device name

   lsblk|grep crypt
   

   Get UUID

   blkid|grep crypto_LUKS|cut -d \" -f 2
   

   Listing 7: /etc/crypttab (excerpt)

   nvme0n1p2_crypt UUID=11111111-1111-1111-1111-111111111111 none luks,discard,keyscript=/usr/local/sbin/openluksdevices.sh
   

7. Add cryptroot info to your initramfs config

   Listing 8: /etc/initramfs-tools/conf.d/cryptroot

   CRYPTROOT=target=nvme0n1p2_crypt,source=/dev/disk/by-uuid/11111111-1111-1111-1111-111111111111
   

8. Add usb_storage module to initramfs

   Listing 9: /etc/initramffs-tools/modules (excerpt)

   usb_storage
   

9. Add a script to add a udev rule to the initrd

   Listing 10: /etc/initramfs-tools/hooks/udevusbkey.sh

   #!/bin/sh
   # udev-usbkey script
   ###taken from
   ###http://www.oxygenimpaired.com/ubuntu-with-grub2-luks-encrypted-lvm-root-hidden-usb-keyfile
   PREREQ="udev"
   prereqs()
   {
   echo "$PREREQ"
   }
   
   case $1 in
   prereqs)
   prereqs
   exit 0
   ;;
   esac
   
   . /usr/share/initramfs-tools/hook-functions
   
   # Copy across relevant rules
   
   cp /etc/udev/rules.d/99-custom-usb.rules ${DESTDIR}/lib/udev/rules.d/
   
   exit 0
   

   Make it executable:

   chmod a+x /etc/initramfs-tools/hooks/udevusbkey.sh
   

10. Modify grub config (ignore fb/fbcon if you don't want those)

    Listing 11: /etc/default/grub (excerpt)

    GRUB_CMDLINE_LINUX_DEFAULT="quiet fb=false fbcon=rotate:1 rootdelay=20 cryptopts=target=nvme0n1p2_crypt,source=/dev/disk/by-uuid/11111111-1111-1111-1111-111111111111,keyscript=/usr/local/sbin/openluksdevices.sh"
    

11. Update initramfs and grub

    update-initramfs -u
    update-grub
    

    Follow the linked guide if you want to unpack the initramfs and verify contents, or just try it. You can also use lsinitramfs for a quick look. What could go wrong?

Dreadnought has replaced chaos as my desktop. This mostly entailed adding a DisplayPort MST hub to allow four displays, and rearranging my desk.

It is a spec boost in single core CPU speed, and GPU speed. It has fewer CPU cores, and half the RAM though.

Some notable things that happened since then:

• My eSATA 4TB drive went bad, and the storage mirror became a single disk that I'm using ZFS snapshots/send to maintain copies of.
• Swapped the WiFi card for a 2.5gbit ethernet adapter (M.2 A+E key format)
• Linux MST crashes which have hopefully been resolved by building a kernel with patch from the thread linked here:Redhat bug

That's all I can recall at the moment. Overall it's doing a good job as a desktop, but the smaller fans can get a bit whiny under load compared to the 120mm fans that just whoosh a bit louder.

Dreadnought got moved into a Full ATX case, the 'Zalman i4'. Before it was in a 'Inwin BP691' ITX case with 'ASRock A520M-ITX​/ac' motherboard. Initially I intended to use a 'Asus B350-F Gaming' motherboard that I had spare, but decided to swap with chaos' 'Asus Prime X470-PRO' since it has better PCI-E expansion.

Cable routing in these segregated bottom cases is a pain. Constant flipping the case back and forth. Poke the cable through, plug it in, manage any excess. The end result looks alright.

In this upgrade I gained:

• 32GB memory (from spare 16GB set I had)
• External ZFS mirror became internal
• 4-port Firewire 800 card (dual controller)
• Extra graphics card (Radeon WX Pro 2100). With the onboard it gives theoretical 9 displays.
• PCIE DisplayPort to USB C (DisplayPort Alternate) adapter
• Extra M.2 slot. I stuck an SSD in there, and might move my 2.5" drive contents to it.
• A bigger heatsink. I had space, so I installed CM Hyper 212 tower heatsink. Before it was Noctua NH-L9a.

I lost:

• DDR4-3600 speed memory (down to 3200), memory went to justice (gaming pc)
• 2.5GbE adapter, I was using the M.2 Wifi slot for this. Substituted a 1G adapter for now.
• Internal Blu-ray drive

Just the motherboard

Board headers close up

Felt tape to prevent drive rattle

Cable management

Everything in place

Expansion cards

Back of expansion cards

Another neat thing for later is the case's vertical GPU mount. I happen to have a PCIE to PCI bridge with two PCI slots that could be mounted there to provide legacy expansion. Couldn't think of a use for now, but I mocked it up a little bit for fun.

39

The Fractal Silent R2 fan I had on the tower heatsink began ticking. It's older and I had it facing downward. I replaced it with a PCCooler F5 R120 which is surprising heavy (190g vs 100g for the previous), and claims to have fluid dynamic bearings.

There is a slight issue when mixing this PWM CPU fan with a DC fan on CPU_OPT on this Asus board. Now the CPU_OPT fan always runs at full speed, so I guess I need to get another PWM controlled fan.

I also modded the other daisy-chained fans to disconnect the tachometer line after the first fan. I thought this would fix the sensor reading jumping up randomly. It probably improved it a bit, but now I notice asus_wmi sensor just randomly jumps up even on ports with just a single fan.

Fan connections for reference:

Since I moved to using two cards I found I could crash X if I enabled a monitor behind a DisplayPort MST hub on the second card.

I was able to verify that it didn't crash if I put the MST hub on the primary card so I've gone with that solution.

Looking back it may have been an issue with autorandr setting the incorrect CRTC, but I will need to test that another time.

This seems to have created a new issue. With my sideways L-shaped monitor config Xorg seems to think my monitors are in a non-contiguous configuration. Now it lets my cursor go into the non-visible areas which is really annoying.

It turns out Xorg fails to properly test for continuous monitors when multiple cards are involved. If the connector between two monitors is a monitor on a different card Xorg will assume there is no continuity, and let your cursor go into the non-visible space.

This machine has been running fine, but I decided to install a serial port on the motherboard header. During the install I:

• Removed the firewire card
• Plugged in the serial port header
• Reinstalled the firewire card
• Attached a null modem cable to a second PC
• Swapped some Displayport cables around

Then the machine refused to post. It also seemed to refuse to reset the BIOS, as normally that would turn the RGB back on. I started pulling cards, unplugging everything, and said lots of curses. No POST, no beeps, nothing.

Finally I got the machine out, pulled the heatsink (because it blocks a memory slot), and removed a pair of RAM sticks. It's back alive. Put the sticks back, and dead. Disable DOCP (memory back at 2133), rearrange the pairs so they're opposite the previous config. Boot and enable DOCP again, and everything works normally. All the devices go back in, and it is working like normal.

I attached the serial cable to the other PC, and it died again. I determined I could at least pull the other pair of RAM sticks to resolve it (saves removing the heatsink). I decided it was some weird voltage or ground loop issue so I made some changes to the setup. They were:

• Swapped my USB switch for another one I had been meaning to try
• Added an internal USB 2.0 hub that gets power from the power supply
• Attached most of my USB 2.0 stuff to that hub

This is way too many hubs, but it seems to have resolved the issue for now. I booted with the serial cable attached to my second PC without issue.

21

I got some new fans (received in exchange for reviews).

First there is this weird triple stacker LTC CF-121D. It's 3 RGB fans, but they only connect together in a line, and have a single cable. I replaced my 3 front fans with them. They PWM reasonably low (800 rpm, I've got them around 980), and are pretty quiet at low speeds. I was going to try the RGB, but it's the ARGB 3-pin 5V variety, and my board only has the 4-pin 12V RGB.

I also swapped the rear stock Zalman fan for a PWM Thermalright TL-P12. Now I can keep it on the CPU OPT header without it running full speed.

The new connection reference:

Things look like this now:

Front fan array

Internal view of front fans

Rear fan

New fan speeds