Update March 2017: I have an updated version of this procedure for VyOS, the open source community fork of Vyatta, available in a new post: VyOS on Alix 2C1 Single Board Computer.

With the impending move to an apartment in Georgia and the migration of my rack full of servers to a hosting provider, there’s no longer a need for me to run my Vyatta VC router on a beefy dual-CPU RAIDed DL360 G3 HP Proliant server chassis. I found an older PCEngines Alix 2c1 single board computer (433 MHz AMD Geode LX700 , 128MB DDR DRAM, CompactFlash (CF) card socket, MiniPCI, 3x 10/100 ethernet) lying around, and decided to turn that into the new router. But I’ve been so spoiled by Vyatta’s good performance (well, at least on an x86 server) and the real CLI, so I don’t think I can go back to something like m0n0wall or pfSense, and since it’s going to be my only network services box (also doing DNS, DHCP, firewalling, NAT, and maybe IPsec VPN) it’s not viable to use the type of older Cisco or Juniper hardware that I can afford.

The down side is that Vyatta isn’t really designed or tuned for small systems, let alone CF media that doesn’t take too well to lots of writes. So, I’m going to begin experimentation with doing a CF install of the current Vyatta Core 6.3, and we’ll see how it goes and what tuning I do over time.

I found two relatively good references; a post on the vyatta.org forum from 2008, relating to Vyatta version 4 (also on the author’s blog), and a blog post detailing a more complex SquashFS/tmpfs/UnionFS read-only Vyatta install. Given my relatively short timeframe and little free time, I decided to try the former approach for now, and plan to make a more customized and tuned CF version of Vyatta in the future.

Creating the actual disk image:

My development platform at the moment is an intel-based MacBook Pro, running MacOS X 10.6.4 and VirtualBox 4.0.12. As much of a Linux fan as I am, my work laptop runs Mac (like everyone else in the office) and lately I can’t guarantee that I’ll be at my desktop long enough to finish anything. The target is an Alix2c1 with a 2GB SanDisk Ultra CF card (yes, I know an industrial card would be better, but I couldn’t get my hands on one). For starters, I created a new VirtualBox VM with the following settings:

  • OS Type: Linux 2.6
  • Base Memory: 128MB
  • Boot Order: Floppy, CD-ROM, Hard Disk
  • IDE Controller Primary: mounted vyatta-livecd_VC6.3 ISO image
  • IDE Controller Secondary: RAW VMDK image (created below)
  • Audio: None
  • Network: Disabled (this is important, as Vyatta saves the interfaces by hardware address, and it would require some config editing and reboots to change them)
  • Serial Port: disconnected (but present)

One difficulty I ran into on Mac is mounting the raw CF card in the VirtualBox guest. I plugged it in via a USB reader, and of course it automatically mounted in MacOS. I ejected it and the /dev/disk1 device disappeared. It turns out that the full procedure (as far as I could tell) for Mac is:

  • Plug in the CF card and reader.
  • It should automount. Run mount to see what the actual device is - in my case, the /dev/disk1s1 partition was mounted, so the disk is /dev/disk1.
  • Run sudo umount -f /dev/disk1. It seems that the MacOS automounter has a god complex, so you may need to re-run this command quite a few times throughout the process if you get device or resource busy errors.
  • In an appropriate directory, create the raw VMDK image with: VBoxManage internalcommands createrawvmdk -filename rawdisk.vmdk -rawdisk /dev/disk1.
  • When creating your VM, you’ll have an option to select Use an Existing Virtual Disk. Use that option, and select the file created in the last step.

Once that’s done, and you’ve setup the VM with the raw disk, boot the VM (should boot to the Vyatta LiveCD), login as usual for an install (vyatta:vyatta), and the the fun begins:

  1. At the prompt after logging in, sudo su -
  2. Edit /opt/vyatta/sbin/install-system (hint: Vyatta has nano and vi installed. nano -c filename shows line numbers) and change the ROOT_FSTYPE variable (line 78 in VC6.3) from “ext4” to “ext2”.
  3. Run install-system. I used all default options (including one partition) and it seemed to work fine. It took a minute or two to create the ext2 filesystem on my 2GB CF card.
  4. The file copy took even longer… so be patient, or have a book handy.
  5. When system-install finishes and you get the root prompt back, before rebooting, continue with some minor tweaks:
  6. mkdir /mnt/temp
  7. mount /dev/sda1 /mnt/temp
  8. cd /mnt/temp
  9. Edit boot/grub/grub.cfg and change all occurrences of “root=UUID=…” entries for the “linux” lines (lines 13, 18, 23, 28 in my grub.cfg) to “root=/dev/sda1”. My only real reason for this change is so that I can move my altered config files (config.boot, fstab and grub.cfg) with minimal changes when I upgrade or make a different vyatta CF card, without having to update the UUID for the new partition.
  10. Edit etc/fstab and change the “UUID=…” device to ”/dev/sda1”.
  11. shutdown. Once the VM is stopped, you can remove the CF card.
  12. The PCEngines Alix.2 boards use a default serial console speed of 38400 baud. Pretty much every network device, plus Linux and Vyatta, use a default speed of 9600 baud. Once I got the CF card installed in the Alix board and hooked it up to my laptop (null modem cable to a PL-2303 based USB to serial adapter, minicom for terminal emulation), I set my terminal emulator to 38400 8N1, powered the board, and then pressed ‘s’ during POST to get into BIOS settings. Option ‘9’ sets the Alix to 9600 baud, ‘Q’ to quit, and ‘Y’ to save changes permanently. The board will reboot, and once the terminal emulator is set back to 9600 baud, serial console should work fine both in BIOS and in the OS.

If all worked well, you should be able to boot into Vyatta and login as the default “vyatta” user (which you set a password for during the install). Assuming you know your way around Vyatta, it’s pretty standard from here, though there are a few things you may want to check or configure right away:

  1. In configuration mode (configure) run show interfaces. All of your physical ethernet interfaces should appear, along with their MAC addresses.
  2. Some changes to reduce the number of log writes to the CF card: set system syslog console facility all level notice and set system syslog global facility protocols level notice.
  3. Configure interfaces. with firewalls, IP addresses or DHCP, etc.
  4. Do whatever other configuration you need for a minimal system - dhcp, dns, nat, etc.

And that’s it - this should give you a working Vyatta system on CF on an Alix board. Stay tuned, hopefully in a month or so I’ll get around to customizing it a bit more, based on the second blog entry linked above.


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