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 2015.03.29

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-b23105da ami-bc3105d4 ami-1a3c0872 ami-183c0870
us-west-1 ami-8bf717cf ami-89f717cd ami-a3f717e7 ami-a1f717e5
us-west-2 ami-2bbe901b ami-29be9019 ami-71be9041 ami-0fbe903f
eu-central-1 ami-bea19ca3 ami-bca19ca1
eu-west-1 ami-e535ae92 ami-e735ae90 ami-c335aeb4 ami-c535aeb2
ap-southeast-1 ami-8a88b8d8 ami-8488b8d6
ap-southeast-2 ami-2199ea1b ami-2399ea19
ap-northeast-1 ami-477b8947 ami-457b8945 ami-157b8915 ami-117b8911
sa-east-1 ami-37368d2a ami-35368d28
cn-north-1 ami-ca26b4f3 ami-c826b4f1

Paravirtual Images

region ebs
paravirtual
x86_64
s3
paravirtual
x86_64
ebs
paravirtual
i386
s3
paravirtual
i386
us-east-1 ami-dc3d09b4 ami-da3d09b2 ami-c63d09ae ami-c23d09aa
us-west-1 ami-edf818a9 ami-e3f818a7 ami-2df81869 ami-23f81867
us-west-2 ami-a7be9097 ami-a5be9095 ami-a1be9091 ami-bfbe908f
eu-central-1 ami-76a09d6b ami-7aa09d67 ami-3aa09d27 ami-38a09d25
eu-west-1 ami-2b2ab15c ami-2f2ab158 ami-6d2bb01a ami-6f2bb018
ap-southeast-1 ami-f689b9a4 ami-f089b9a2 ami-ca89b998 ami-c489b996
ap-southeast-2 ami-9199eaab ami-9399eaa9 ami-a799ea9d ami-a199ea9b
ap-northeast-1 ami-d1788ad1 ami-cf788acf ami-b37b89b3 ami-af7b89af
sa-east-1 ami-cf368dd2 ami-cd368dd0 ami-4d368d50 ami-53368d4e
cn-north-1 ami-c426b4fd ami-c226b4fb ami-3827b501 ami-c626b4ff

Release 2015.03.11

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-7c012714 ami-7a012712 ami-e4e7c18c ami-e0e7c188
us-west-1 ami-bf1ef9fb ami-bd1ef9f9 ami-0f1dfa4b ami-0d1dfa49
us-west-2 ami-55ac8e65 ami-53ac8e63 ami-c3b89af3 ami-c1b89af1
eu-central-1 ami-14685509 ami-1a685507
eu-west-1 ami-b7811cc0 ami-c9811cbe ami-51b12c26 ami-53b12c24
ap-southeast-1 ami-eaa99fb8 ami-e4a99fb6
ap-southeast-2 ami-952151af ami-972151ad
ap-northeast-1 ami-a39e74a3 ami-a19e74a1 ami-5beb015b ami-59eb0159
sa-east-1 ami-2bc17936 ami-29c17934
cn-north-1 ami-b635a78f ami-b435a78d

Paravirtual Images

region ebs
paravirtual
x86_64
s3
paravirtual
x86_64
ebs
paravirtual
i386
s3
paravirtual
i386
us-east-1 ami-d80f29b0 ami-c60f29ae ami-240f294c ami-200f2948
us-west-1 ami-c71cfb83 ami-c51cfb81 ami-351cfb71 ami-2b1cfb6f
us-west-2 ami-15b29025 ami-13b29023 ami-c5ad8ff5 ami-c3ad8ff3
eu-central-1 ami-5268554f ami-5068554d ami-5c685541 ami-2268553f
eu-west-1 ami-4f831e38 ami-41831e36 ami-87801df0 ami-99801dee
ap-southeast-1 ami-d696a084 ami-d096a082 ami-7c96a02e ami-7e96a02c
ap-southeast-2 ami-23225219 ami-2d225217 ami-d52151ef ami-d72151ed
ap-northeast-1 ami-e19f75e1 ami-df9f75df ami-db9f75db ami-d99f75d9
sa-east-1 ami-8fc17992 ami-8dc17990 ami-9dc17980 ami-63c1797e
cn-north-1 ami-ae35a797 ami-ac35a795 ami-a235a79b ami-a035a799

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.