projects::arch linux on ec2

Arch Linux
Amazon Web Services

summary

Arch Linux's minimalistic philosophy and high degree of customizability makes it a great choice for compute cloud deployment. It's light, fast, and scalable.

I am doing releases of Arch Linux as Amazon EC2 AMIs roughly twice per month.

contact

IRC Join us on irc.freenode.net in #archlinux-ec2!

If you find a bug or have any other comments, please send me an email, or ping me on twitter.

NOTE: This project is not run, sponsored, or endorsed by my employer.

current releases

Release 2015.02.25

HVM Images

region ebs
hvm
x86_64
s3
hvm
x86_64
ebs
hvm gpu
x86_64
s3
hvm gpu
x86_64
us-east-1 ami-a64914ce ami-a44914cc ami-ac4914c4 ami-aa4914c2
us-west-1 ami-b918fdfd ami-bf18fdfb ami-af18fdeb ami-ad18fde9
us-west-2 ami-75fddc45 ami-73fddc43 ami-b1fddc81 ami-4ffddc7f
eu-central-1 ami-44f6c459 ami-4af6c457
eu-west-1 ami-9f891fe8 ami-91891fe6 ami-d9ba2cae ami-dbba2cac
ap-southeast-1 ami-9c3700ce ami-9e3700cc
ap-southeast-2 ami-c3e492f9 ami-cde492f7
ap-northeast-1 ami-1f3bd61f ami-1b3bd61b ami-413bd641 ami-3f3bd63f
sa-east-1 ami-4bfa4356 ami-49fa4354
cn-north-1 ami-8e32a0b7 ami-8c32a0b5

Paravirtual Images

region ebs
paravirtual
x86_64
s3
paravirtual
x86_64
ebs
paravirtual
i386
s3
paravirtual
i386
us-east-1 ami-b4712cdc ami-b2712cda ami-0e461b66 ami-0c461b64
us-west-1 ami-6d668329 ami-63668327 ami-e31affa7 ami-e11affa5
us-west-2 ami-6fc2e35f ami-6dc2e35d ami-55ffde65 ami-53ffde63
eu-central-1 ami-68f4c675 ami-6ef4c673 ami-14f7c509 ami-1af7c507
eu-west-1 ami-13bd2b64 ami-15bd2b62 ami-79b2240e ami-7bb2240c
ap-southeast-1 ami-b63007e4 ami-b03007e2 ami-d83f088a ami-da3f0888
ap-southeast-2 ami-8fe096b5 ami-89e096b3 ami-79e29443 ami-7be29441
ap-northeast-1 ami-4703ee47 ami-4303ee43 ami-2b31dc2b ami-2931dc29
sa-east-1 ami-99fc4584 ami-9ffc4582 ami-1dfd4400 ami-e3fa43fe
cn-north-1 ami-e632a0df ami-e432a0dd ami-9832a0a1 ami-a632a09f

Release 2015.02.08

HVM Images

region ebs
hvm
x86_64
s3
hvm
x86_64
ebs
hvm gpu
x86_64
s3
hvm gpu
x86_64
us-east-1 ami-fcfdb394 ami-fafdb392 ami-c80b42a0 ami-f40b429c
us-west-1 ami-f0c6ddb5 ami-f6c6ddb3 ami-62fbe027 ami-60fbe025
us-west-2 ami-57edb767 ami-55edb765 ami-596c4969 ami-556c4965
eu-central-1 ami-ac96a5b1 ami-b296a5af
eu-west-1 ami-3573fb42 ami-3773fb40 ami-07018970 ami-1901896e
ap-southeast-1 ami-1c16234e ami-1e16234c
ap-southeast-2 ami-3f5e2905 ami-395e2903
ap-northeast-1 ami-53ea0e53 ami-51ea0e51 ami-effc18ef ami-edfc18ed
sa-east-1 ami-bb64dba6 ami-b964dba4
cn-north-1 ami-c40597fd ami-c20597fb

Paravirtual Images

region ebs
paravirtual
x86_64
s3
paravirtual
x86_64
ebs
paravirtual
i386
s3
paravirtual
i386
us-east-1 ami-0e074e66 ami-0c074e64 ami-660a430e ami-640a430c
us-west-1 ami-4ef9e20b ami-4cf9e209 ami-02fbe047 ami-00fbe045
us-west-2 ami-4f71547f ami-4b71547b ami-dd6c49ed ami-db6c49eb
eu-central-1 ami-1a96a507 ami-1896a505 ami-e697a4fb ami-e497a4f9
eu-west-1 ami-c7078fb0 ami-d9078fae ami-7f028a08 ami-71028a06
ap-southeast-1 ami-0e17225c ami-0817225a ami-6c17223e ami-6e17223c
ap-southeast-2 ami-015b2c3b ami-035b2c39 ami-395c2b03 ami-3b5c2b01
ap-northeast-1 ami-5df1155d ami-5bf1155b ami-1ff1151f ami-1df1151d
sa-east-1 ami-8961de94 ami-8f61de92 ami-9561de88 ami-9b61de86
cn-north-1 ami-d00597e9 ami-de0597e7 ami-c80597f1 ami-d60597ef

tools

The EC2 image build process is public, but the AMI registration portion is not. Here are the necessary tools to create an image file, but see the 2013-05-26 news post for information on how to register the images in EC2.

  • ami-build-backend - These files are held on the PXE server, and fetched when the guest boots.
  • ami-builder-image - This is a fork of archiso with some changes to automatically pull down my install script and do a few other things.
  • ec2-packages - These are the sources for all the packages contained in the 'ec2' Pacman repository.

recent changes and news

  • 2014-07-26

    I've added AMIs for the Beijing, China (cn-north-1) region.

  • 2014-06-27

    We're now up to Linux 3.15.2. I've removed xen-fbfront from the initramfs, because the module was causing 30-second boot delays:

    [    2.050081] tsc: Refined TSC clocksource calibration: 2793.267 MHz
    [    6.370066] xenbus_probe_frontend: Waiting for devices to initialise: 25s...20s...
    [   12.390306] random: nonblocking pool is initialized
    [   16.370070] 15s...10s...5s...0s...
    [   31.371241] xenbus_probe_frontend: Timeout connecting to device: device/vfb/0 (local state 3, remote state 1)
    

    The module is not required for an instance to boot correctly, so it can be removed from the initramfs. If you are running an AMI older than the 2014.06.27 release and would like to improve your instance's boot time, you can prune the module yourself:

    [root@ip-10-0-155-25 ~]# grep fbfront /etc/mkinitcpio.conf 
    MODULES="button ipmi-msghandler ipmi-poweroff virtio virtio-blk virtio-net virtio-pci virtio-ring
    xen-blkfront xen-fbfront xen-netfront xen-pcifront xen-privcmd hv_storvsc hv_balloon
    hv_vmbus hv_utils hv_netvsc ixgbevf"
    [root@ip-10-0-155-25 ~]# sed -ri 's/xen-fbfront //g' /etc/mkinitcpio.conf 
    [root@ip-10-0-155-25 ~]# mkinitcpio -p linux-ec2
    ==> Building image from preset: /etc/mkinitcpio.d/linux-ec2.preset: 'default'
      -> -k /boot/vmlinuz-linux-ec2 -c /etc/mkinitcpio.conf -g /boot/initramfs-linux-ec2.img -S autodetect
    ==> Starting build: 3.15.2-1-ec2
      -> Running build hook: [base]
      -> Running build hook: [udev]
      -> Running build hook: [modconf]
      -> Running build hook: [block]
      -> Running build hook: [filesystems]
      -> Running build hook: [growfs]
      -> Running build hook: [keyboard]
      -> Running build hook: [fsck]
    ==> Generating module dependencies
    ==> Creating gzip initcpio image: /boot/initramfs-linux-ec2.img
    ==> Image generation successful
    [root@ip-10-0-155-25 ~]#
    

    After removing xen-fbfront from mkinitcpio.conf's MODULES section, subsequent reboots will be 30 seconds shorter. Before:

    [root@ip-10-0-155-25 ~]# systemd-analyze
    Startup finished in 32.530s (kernel) + 3.997s (userspace) = 36.528s

    After:

    [root@ip-10-0-155-25 ~]# systemd-analyze
    Startup finished in 2.345s (kernel) + 2.092s (userspace) = 4.438s
  • 2014-06-19

    The AMI now uses systemd's networkd, timesyncd, and resolved services. This makes the AMI have a significantly smaller footprint. Right now our biggest non-core packages are CUDA (in the GPU AMI) and cloud-init, which has a large dependency chain. I'd like to slim things even further, but I'll need to investigate how to do so.

  • 2014-03-24

    We're up to Linux 3.13.7 for the ec2 kernel and 3.10.34 for the ec2-lts kernel. I didn't make a news post earlier, but kernels are now built with 'debug' and 'strip' options, which will create split-out debug information packages (i.e. linux-ec2-debug, linux-ec2-lts-debug). This is useful for tools like perf, oprofile, and systemtap. Note that the -debug packages are compressed with 'lrzip'. New AMI builds have lrzip preinstalled, but if you're running an instance based on one of the older AMIs, you will need to install lrzip before you can make use of the -debug packages.

  • 2013-11-28

    New AMIs are being built right now and contain a couple changes:

    • EBS root volumes are now automatically resized to fill the block device. You can take advantage of this feature by launching an instance with a root volume size larger than the snapshot.
    • The resolv.conf file permissions are now 0644, allowing non-root users to resolve hostnames.

  • 2013-11-26

    Geoff H. and David B. both reported an issue with the current AMI release. The /etc/resolv.conf permissions are set to 0600 rather than 0644, which means that non-root users cannot resolve hostnames to IP addresses. This is an unintentional regression, most likely caused by a default 'umask' change in some package. dhclient will create a new resolv.conf and copy it over any existing file, which preserves the target file's permissions. But if no such file exists, then the permissions of the source file are copied. Previously, this worked fine because the file was generated with 0644 permissions, but now it's being generated with 0600. I've implemented a fix for future AMI builds. In the meantime, if non-root users need to perform DNS requests in your instances, be sure to do 'chmod 0644 /etc/resolv.conf'.

  • 2013-11-06

    A new ec2-pacman-mirrors package is available, and will provide your instances with optimal Arch Linux mirrors for your EC2 region. The upgrade path is as follows:

    1. Edit /etc/pacman.conf, change 'ec2' mirror URL to https://s3.amazonaws.com/arch-linux-ami/repo/$arch
    2. Run 'pacman -Sy ec2-pacman-mirrors'

    New AMIs will be published very shortly which use the new mirror list and point to the new EC2 package repository.

  • 2013-05-26

    I've added some links to this page, which are the complete set of files needed to do an EC2 image build. This does not include the AMI registration process, however. The tools Amazon provides for HVM AMI registration are still under NDA at the moment, and the bits necessary to do that are included in my AMI registration tools. So I can't make those public right now. The process itself can be replicated relatively easily, though:

    1. Build your VM image using the build-backend and builder-image repos above. PXE is what I use, but you could just as easily make it into an ISO or something. If you intend to do an S3-backed AMI, you will need to make the image no larger than 10GB (I use 8GB).
    2. Trim the image down (I do a 'mount -o loop,discard' on the image, then 'fstrim' the mount point, making the image into a sparse file).
    3. Tarball the image (tar cSzf, S to preserve the sparseness).
    4. Upload the tarball to S3.
    5. In each region, launch an instance and attach an empty 8GB EBS volume to them.
    6. On each of those instances, download the tarball and extract with 'tar xSf'.
    7. Use 'ddpt', an enhanced dd which pays attention to the sparseness of the image, to copy the raw image file into the EBS device. I use "ddpt if=<imagefile> of=/dev/xvdf bs=512 conv=sparse oflag=sparse,fsync". The sparseness aspect is important, because otherwise you're copying empty blocks onto the EBS device, which makes the snapshot take much longer, and is really just a waste of time. EBS volumes already read-as-zero, so there's no sense copying zero blocks.
    8. Detach the EBS volume and terminate the instances.
    9. Snapshot the EBS volume.
    10. Delete the volume (not needed now).
    11. Use ec2-register to create an AMI from the snapshotted volume.

  • 2013-03-22

    I've started creating AMIs which have CUDA preinstalled. These are for the cg1.4xlarge instance type.

  • 2013-02-05

    Nothing too exciting lately. Today's release has Linux 3.7.6.

  • 2012-11-22

    New AMI releases, now with cloud-init. Thanks to Jeremy D for contributing his time and effort to making cloud-init work well on Arch Linux.

  • 2012-11-12

    Released new AMIs, primarily for the new AWS region in Sydney, Australia (ap-southeast-2).

  • 2012-11-08

    Today's AMIs are released. Nothing too fancy in this build: just updated packages, including linux-ec2 3.6.6-1.

  • 2012-10-21

    I've added a new linux-ec2 package which contains a patched v3.6.2 kernel. There are a few major differences between this kernel and the Arch Linux stock kernel:

    • Hangs on Xen fixed (patches from 3.6.3 stable-queue).
    • CONFIG_PREEMPT_VOLUNTARY instead of CONFIG_PREEMPT, this will allow for better scheduling as a domU.
    • CONFIG_HZ=100 instead of CONFIG_HZ=300, this allows for better performance on many-CPU instances, as there are fewer timer interrupts to preempt other tasks.
    • Many drivers removed, particularly those that didn't make sense for running in an EC2 instance. I've left drivers for my own hardware so I can experiment with it as a dom0 kernel as well. The kernel size is roughly half the stock Arch Linux kernel due to the stripped drivers.

    I am also building new AMIs right now, and am beating the i386 AMIs into working order. Once done I'll publish the next release (which should be 2012.10.21). Once it's available, it will show in the tables above.

  • 2012-10-16

    Do not upgrade HVM instance kernels to anything between 3.6.0 and 3.6.2 inclusive. You must wait for 3.6.3 or else your instance will not boot. We're currently waiting on this patch to be integrated into the mainline stable tree. This is also why I am probably not doing an AMI release this week, as the HVM AMIs would be totally broken.

    I've also taken a look at building i386 (well, i686) AMIs. I'm not really sure that it's worth the effort. Nobody really uses 32-bit AMIs anymore, and we'd need to fork the kernel just to make it happen. For now, i686 is on ice.

release notes

These AMIs are as close to a "vanilla" install as I can make them without making them functionally impaired on EC2. But here's the complete list of differences between the EC2 builds and a stock install:

  • High performance kernel specifically for EC2, including paravirtualization support on i386 and x86_64 AMIs, and more Xen-friendly process scheduling.

  • Kernel modules included in initrd, some of which are relevant outside of EC2 contexts (e.g. if you want to run the image in a non-EC2 environment such as KVM or Hyper-V):

    • KVM: virtio virtio-blk virtio-net virtio-pci virtio-ring
    • Xen: xen-blkfront xen-netfront xen-pcifront xen-privcmd
    • Hyper-V: hv_storvsc hv_balloon hv_vmbus hv_utils hv_netvsc
    • IPMI (e.g. EC2 reboot request): button ipmi-msghandler ipmi-poweroff
    • EC2 enhanced networking SR-IOV driver: ixgbevf
  • Extra packages installed: audit, cloud-init, ec2-keyring, ec2-pacman-mirrors, irqbalance, lrzip, openssh, rng-tools, rsync, systemd-sysvcompat

  • Added an extra package source for ec2-specific packages. The repository currently contains numerous packages useful on EC2. You can view the list of packages by doing 'pacman -Sy; pacman -Ss | grep ^ec2'

  • Additional services enabled at boot: rngd, sshd, cloud-init, irqbalance, auditd, systemd-networkd, systemd-timesyncd, systemd-resolved

  • User's public key is pulled from the EC2 instance metadata service at startup, and added to /root/.ssh/authorized_keys

  • SSH configured with 'PasswordAuthentication no', enforcing public key authentication

  • pacman loads (and automatically lsigns) the 'archlinux' and 'ec2' keyrings on the first boot (the latter keyring contains my public key used for package signing in the ec2 repo).

  • pacman mirror list is automatically selected at boot based on a list I created (based on rankmirrors run on instances in each region). These lists are provided by the package ec2-pacman-mirrors, which is in the ec2 repo.

  • dhclient is used instead of dhcpcd for robustness reasons. I found that dhcpcd gave up too quickly if it tried to do a DHCPREQUEST when the vif wasn't completely up, making the EC2 instance inaccessible.

  • dhclient is configured to retry forever, and request the following dhcp options: subnet-mask, broadcast-address, time-offset, routers, domain-name, domain-name-servers, host-name, interface-mtu, fqdn

  • /usr/bin/pinentry is symlinked to /usr/bin/pinentry-curses instead of the default pinentry-gtk, since gtk isn't available in this install and the primary access method is SSH.