How to create an Amazon Elastic Compute Cloud EC2 Machine Image (AMI)

(UPDATED: 05/31/2010)

This how to article will go over creating a Amazon Elastic Compute Cloud (EC2) Machine Image (AMI) from scratch. In this particular example we are creating a Centos 5.3 64bit AMI from beginning to end. For those that are interested in taking advantage of cloud computing, hopefully you find this blog article helpful. Note this blog also can be generalized for Centos 5, 5.1, 5.2 most versions of Redhat, and Fedora 64bit and 32bit.

First thing is first you are going to need to sign up for an Amazon Web Services account specifically S3 Storage and EC2 Elastic Compute Cloud here. You will need a credit card and some basic info, and will immediately get the following info:

AWS Account Number
S3 KEY "yourkeynumber"
S3 SECRET KEY "yoursecretkey"
EC2 PRIVATE KEY "pk-yourprivatekey.pem"
EC2 CERTIFICATE "cert-yourcertificate.pem"

You will need to work off of a server with the same distro you would like your image to be in my case that would be Centos 5 also note you will want to work on a server with enough disk space to create and image on.

Time to login become root and go to town:

Put your two .pem files the cert and pk in the directory ~/.ec2

[root@server]$ mkdir ~/.ec2

Create some directories to work from and put your working files in make sure its on your largest partition in my case its /opt.

[root@server]$ mkdir /opt/EC2AMIFILES
[root@server]$ mkdir /opt/EC2TOOLS
[root@server]$ mkdir /opt/EC2AMIIMAGE
[root@server]$ mkdir /opt/EC2YUM

Download and extract the Amazon AMI tools into the /opt/EC2TOOLS you should have subdirectories that look like /opt/EC2TOOLS/bin etc…

[root@server]$ cd /opt/EC2TOOLS
[root@server]$ wget http://s3.amazonaws.com/ec2-downloads/ec2-ami-tools.zip
[root@server]$ unzip ec2-ami-tools.zip
[root@server]$ cd ec2-ami-tools-1.3-31780
[root@server]$ mv * ../
[root@server]$ cd ../
[root@server]$ rmdir ec2-ami-tools-1.3-31780/

Setup your .bashrc file to have proper pathing to EC2 resources

[root@server]$ vi ~/.bashrc
 
export PATH=$PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin:/opt/EC2TOOLS/bin
export EC2_HOME=/opt/EC2TOOLS
export EC2_PRIVATE_KEY=~/.ec2/pk-yourprivatekey.pem
export EC2_CERT=~/.ec2/cert-yourcert.pem

Enable your .bashrc settings

[root@server]$ source ~/.bashrc

Create an empty file that is about 10GB where the OS files will be worked.

[root@server]$ dd if=/dev/zero of=/opt/EC2AMIIMAGE/ami-centos5.3-64bit-base.img bs=1M count=10240

Create an ext3 filesystem inside the image file.

[root@server]$ /sbin/mke2fs -F -j /opt/EC2AMIIMAGE/ami-centos5.3-64bit-base.img

Mount the image file using the loop-back option, allowing you to treat the image file as if it was a standard disk drive.

[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base
 
[root@server]$ mount -o loop /opt/EC2AMIIMAGE/ami-centos5.3-64bit-base.img /mnt/ami-centos5.3-64bit-base

Prepare the empty image filesystem with paths for system devices and configuration files.

[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base/proc
 
[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base/etc
 
[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base/dev
 
[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base/var
 
[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base/var/cache
 
[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base/var/log
 
[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base/var/lock
 
[root@server]$ mkdir /mnt/ami-centos5.3-64bit-base/var/lock/rpm
 
[root@server]$ /sbin/MAKEDEV -d /mnt/ami-centos5.3-64bit-base/dev -x console
 
[root@server]$ /sbin/MAKEDEV -d /mnt/ami-centos5.3-64bit-base/dev -x null
 
[root@server]$ /sbin/MAKEDEV -d /mnt/ami-centos5.3-64bit-base/dev -x zero

Create the file fstab to store the filesystem configuration.

[root@server]$ vi /mnt/ami-centos5.3-64bit-base/etc/fstab
 
If you are using 64BIT use these fstab entries below
 
/dev/sda1       /      ext3   defaults  1  1
/dev/sdb        /mnt   ext3   defaults  0  0
none            /proc  proc   defaults  0  0
none            /sys   sysfs  defaults  0  0
 
If you are using 32BIT use these fstab entries below
 
/dev/sda1	/		ext3		defaults	1	1
none		/dev/pts	devpts	        gid=5,mode=620	0	0
none		/dev/shm	tmpfs	        defaults	0	0
none		/proc		proc		defaults	0	0
none		/sys		sysfs		defaults	0	0
/dev/sda2	/mnt		ext3		defaults	0	0
/dev/sda3	swap		swap		defaults	0	0

Mount the image’s proc device in advance to avoid problems with using yum.

[root@server]$ mount -t proc none /mnt/ami-centos5.3-64bit-base/proc

Create a YUM config file, note please adjust version and architecture according to which version you are using.
For Centos 5.3 64bit use the following:

[root@server]$ vi /opt/EC2YUM/yum-ami.conf
 
[main]
cachedir=/var/cache/yum
keepcache=1
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=redhat-release
tolerant=1
exactarch=1
obsoletes=1
gpgcheck=1
plugins=1
metadata_expire=1800
 
[base]
name=CentOS-5 - Base
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=x86_64&repo=os
#baseurl=http://mirror.centos.org/centos/5/os/x86_64/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#released updates 
[updates]
name=CentOS-5 - Updates
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=x86_64&repo=updates
#baseurl=http://mirror.centos.org/centos/5/updates/x86_64/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#packages used/produced in the build but not released
[addons]
name=CentOS-5 - Addons
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=x86_64&repo=addons
#baseurl=http://mirror.centos.org/centos/5/addons/x86_64/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#additional packages that may be useful
[extras]
name=CentOS-5 - Extras
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=x86_64&repo=extras
#baseurl=http://mirror.centos.org/centos/5/extras/x86_64/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-5 - Plus
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=x86_64&repo=centosplus
#baseurl=http://mirror.centos.org/centos/5/centosplus/x86_64/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#contrib - packages by Centos Users
[contrib]
name=CentOS-5 - Contrib
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=x86_64&repo=contrib
#baseurl=http://mirror.centos.org/centos/5/contrib/x86_64/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5

If you are creating a 32bit Centos 5 create the following YUM config file instead:

[main]
cachedir=/var/cache/yum
keepcache=1
debuglevel=2
logfile=/var/log/yum.log
pkgpolicy=newest
distroverpkg=redhat-release
tolerant=1
exactarch=1
obsoletes=1
gpgcheck=1
plugins=1
metadata_expire=1800
 
[base]
name=CentOS-5 - Base
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=i386&repo=os
#baseurl=http://mirror.centos.org/centos/5/os/i386/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#released updates 
[updates]
name=CentOS-5 - Updates
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=i386&repo=updates
#baseurl=http://mirror.centos.org/centos/5/updates/i386/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#packages used/produced in the build but not released
[addons]
name=CentOS-5 - Addons
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=i386&repo=addons
#baseurl=http://mirror.centos.org/centos/5/addons/i386/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#additional packages that may be useful
[extras]
name=CentOS-5 - Extras
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=i386&repo=extras
#baseurl=http://mirror.centos.org/centos/5/extras/i386/
gpgcheck=1
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#additional packages that extend functionality of existing packages
[centosplus]
name=CentOS-5 - Plus
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=i386&repo=centosplus
#baseurl=http://mirror.centos.org/centos/5/centosplus/i386/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5
 
#contrib - packages by Centos Users
[contrib]
name=CentOS-5 - Contrib
mirrorlist=http://mirrorlist.centos.org/?release=5&arch=i386&repo=contrib
#baseurl=http://mirror.centos.org/centos/5/contrib/i386/
gpgcheck=1
enabled=0
gpgkey=file:///etc/pki/rpm-gpg/RPM-GPG-KEY-CentOS-5

Perform the operating system installation via yum, installing base OS.

[root@server opt]$ cd /opt/EC2YUM
 
[root@server EC2YUM]$ yum -c yum-ami.conf --installroot=/mnt/ami-centos5.3-64bit-base -y groupinstall Base
 
[root@server EC2YUM]$ cp yum-ami.conf /mnt/ami-centos5.3-64bit-base/etc/yum.conf

Install openssh dependencies to allow you to connect via SSH

[root@server EC2YUM]$ yum -c /opt/EC2YUM/yum-ami.conf --installroot=/mnt/ami-centos5.3-64bit-base install *openssh*
[root@server EC2YUM]$ /usr/sbin/chroot /mnt/ami-centos5.3-64bit-base /sbin/chkconfig sshd --add
[root@server EC2YUM]$ /usr/sbin/chroot /mnt/ami-centos5.3-64bit-base /sbin/chkconfig --level 12345 sshd on

Install precompiled modules supplied by Amazon, since the kernel modules installed by yum are not appropriate for the EC2 environment.

[root@server]$ wget http://www.philchen.com/wp-content/uploads/2009/05/kernel-modules-261633-xenu.tgz
[root@server]$ gunzip -c kernel-modules261633-xenu.tgz | tar -xvf -
[root@server]$ mv 2.6.16.33-xenU /mnt/ami-centos5.3-64bit-base/lib/modules
[root@server]$ /usr/sbin/chroot /mnt/ami-centos5.3-64bit-base /sbin/depmod -ae 2.6.16.33-xenU

If you are installing 32bit use the following download instead

[root@server]$ wget http://www.philchen.com/wp-content/uploads/2009/05/kernel-modules2616-xenu.tgz
[root@server]$ gunzip -c kernel-modules2616-xenu.tgz | tar -xvf -
[root@server]$ cd lib/modules
[root@server]$ mv 2.6.16-xenU /mnt/ami-centos5.3-32bit-base/lib/modules
[root@server]$ /usr/sbin/chroot /mnt/ami-centos5.3-32bit-base /sbin/depmod -ae 2.6.16-xenU

Delete Kudzu from startup since for some reason it messes up your network settings on first startup of the image.

[root@server]$ /usr/sbin/chroot /mnt/ami-centos5.3-64bit-base /sbin/chkconfig --del kudzu

Configure SSH to allow Root login only via key.

[root@server]$ vi /mnt/ami-centos5.3-64bit-base/etc/ssh/sshd_config
 
UseDNS no
PermitRootLogin without-password

Configure the images network settings

[root@server]$ cd /mnt/ami-centos5.3-64bit-base/etc/sysconfig/
 
[root@server sysconfig]$ vi network
 
NETWORKING=yes
HOSTNAME=localhost.localdomain
 
[root@server sysconfig]$ vi /mnt/ami-centos5.3-64bit-base/etc/sysconfig/network-scripts/ifcfg-eth0
 
ONBOOT=yes
DEVICE=eth0
BOOTPROTO=dhcp

This script grabs the public key credentials for your root login.

[root@server]$ vi /mnt/ami-centos5.3-64bit-base/etc/init.d/getssh
 
#!/bin/bash
# chkconfig: 2345 95 20
# description: getssh
# processname: getssh
#
export PATH=:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin
# Source function library.
. /etc/rc.d/init.d/functions
 
# Source networking configuration.
[ -r /etc/sysconfig/network ] && . /etc/sysconfig/network
 
# Check that networking is up.
[ "${NETWORKING}" = "no" ] && exit 1
 
start() {
  if [ ! -d /root/.ssh ] ; then
          mkdir -p /root/.ssh
          chmod 700 /root/.ssh
  fi
  # Fetch public key using HTTP
/usr/bin/curl -f http://169.254.169.254/latest/meta-data/public-keys/0/openssh-key > /tmp/my-key
  if [ $? -eq 0 ] ; then
          cat /tmp/my-key >> /root/.ssh/authorized_keys
          chmod 600 /root/.ssh/authorized_keys
          rm /tmp/my-key
  fi
  # or fetch public key using the file in the ephemeral store:
  if [ -e /mnt/openssh_id.pub ] ; then
          cat /mnt/openssh_id.pub >> /root/.ssh/authorized_keys
          chmod 600 /root/.ssh/authorized_keys
  fi
}
 
stop() {
  echo "Nothing to do here"
}
 
restart() {
  stop
  start
}
 
# See how we were called.
case "$1" in
  start)
    start
    ;;
  stop)
    stop
    ;;
  restart)
    restart
    ;;
  *)
    echo $"Usage: $0 {start|stop}"
    exit 1
esac
 
exit $?
###END OF SCRIPT

Give the getssh proper permissions

#Fixed typo 07/09
[root@server]$ /bin/chmod +x /mnt/ami-centos5.3-64bit-base/etc/init.d/getssh

Configure your init script to be launched in run level 3 and 4

[root@server]$ /usr/sbin/chroot /mnt/ami-centos5.3-64bit-base /sbin/chkconfig --level 34 getssh on

Yum install Ruby and CURL to the image

[root@server EC2YUM]$ cd /opt/EC2YUM/
 
[root@server EC2YUM]$ yum -c yum-ami.conf --installroot=/mnt/ami-centos5.3-64bit-base install ruby
 
[root@server EC2YUM]$ yum -c yum-ami.conf --installroot=/mnt/ami-centos5.3-64bit-base install curl

Install Java to the image, get Java file for your distro jre-6u12-linux-x64.bin and put it in the /mnt/ami-centos5.3-64bit-base

[root@server]$ cd /mnt/ami-centos5.3-64bit-base/
 
[root@server]$ /usr/sbin/chroot /mnt/ami-centos5.3-64bit-base ./jre-6u12-linux-x64.bin

Here is the part where you can install other software you wish or remove it simply by using the chroot command

[root@server]$ /usr/sbin/chroot /mnt/ami-centos5.3-64bit-base (put your commands here to do installs for the image)

Clean up after yourself lowering image size

[root@server ami-centos5.3-64bit-base]$ cd /opt/EC2YUM/
 
[root@server EC2YUM]$ yum -c yum-ami.conf --installroot=/mnt/ami-centos5.3-64bit-base clean all
 
[root@server EC2YUM]$ sync
[root@server EC2YUM]$ umount /mnt/ami-centos5.3-64bit-base/proc
[root@server EC2YUM]$ umount /mnt/ami-centos5.3-64bit-base

Bundle your image

[root@server]$ cd /opt/EC2TOOLS/bin/
 
[root@server bin]$ ./ec2-bundle-image --image /opt/EC2AMIIMAGE/ami-centos5.3-64bit-base.img --prefix ami-centos5.3-64bit-base --cert ~/.ec2/cert-yourcert.pem --privatekey ~/.ec2/pk-yourprivatekey.pem --user youramazonaccountnumber --destination /opt/EC2AMIFILES --arch x86_64

The next step is to ensure you have a target bucket for your EC2 instance with the correct ACL’s you may want to use the FireFox plugin S3 Fox to do this but their are great libraries out their for your desired language. I created a bucket called phils-amis

Give the ACL permission to the bucket you create for your AMI:
6aa5a366c34c1cbe25dc49211496e913e0351eb0e8c37aa3477e40942ec6b97c

Next you will upload your files to the bucket you just designated in my case phils-amis

[root@server]$ cd /opt/EC2TOOLS/bin/
 
[root@server bin]$ ./ec2-upload-bundle --manifest /opt/EC2AMIFILES/ami-centos5.3-64bit-base.manifest.xml --bucket phils-amis --access-key accesskeyhere --secret-key secretkeyhere --location (US, UK, us-west-1, ap-southeast-1)
 
[root@server bin]$ history -c

Now you are just about done all you need to do is register your AMI. I did this part from my Macbook Pro since I had my Amazon Web Services Tools there. You can get these from Amazon keep in mind these tools are different then the AMI tools you have been using. I put mine in /Users/phil/EC2 also I created a .ec2 directory with my cerificate and private key at /Users/phil/.ec2 Also know that you can use the AWS console from their site to register AMI’s add security groups and launch them as well.

My .bashrc file looks like this on my laptop

# .bashrc
 
# User specific aliases and functions
 
alias rm='rm -i'
alias cp='cp -i'
alias mv='mv -i'
 
# Source global definitions
if [ -f /etc/bashrc ]; then
        . /etc/bashrc
fi
 
export PATH=$PATH:/usr/local/bin:/usr/local/sbin:/usr/bin:/usr/sbin:/bin:/sbin:/Users/phil/EC2/bin
export EC2_HOME=/Users/phil/EC2
 
export EC2_PRIVATE_KEY=~/.ec2/pk-yourprivatekey.pem
export EC2_CERT=~/.ec2/cert-yourcertificate.pem
 
export JAVA_HOME=/System/Library/Frameworks/JavaVM.framework/Home/

You now can register our new AMI and get your AMI code

[phil@desktop]$ cd /Users/phil/EC2/bin
[phil@desktop]$ ./ec2-register phils-amis/ami-centos5.3-64bit-base.manifest.xml
IMAGE	ami-youramicode

You will want to create a keypair to launch your AMI

[phil@desktop]$ ./ec2-add-keypair phils-keypair-raw
 
KEYPAIR phil-keypair  1f:51:ae:28:bf:89:e9:d8:1f:25:5d:37:2d:7d:b8:ca:9f:f5:f1:6f
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----

Now create the key basically cut and paste —–BEGIN RSA PRIVATE KEY—– to —–END RSA PRIVATE KEY—– including the two lines into a your keypair file.

[phil@desktop]$ vi phil-key-pair
 
-----BEGIN RSA PRIVATE KEY-----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-----END RSA PRIVATE KEY-----

Time to start your AMI! Note that if you have a 64bit AMI it needs to be started as a large instance.

[phil@desktop]$ /Users/phil/EC2/bin/ec2-run-instances ami-youramiid --instance-type m1.large -k phil-key-pair --region (US, UK, us-west-1, ap-southeast-1)

Time to check the status

[phil@desktop]$ /Users/phil/EC2/bin/ec2-describe-instances
 
RESERVATION	r-0dc52965	027409037432	default
INSTANCE	i-yourinstance	ami-youramiid			pending	phil-key-pair	0		m1.large	2009-02-13T23:51:11+0000	us-east-1c

When it running it will look like this

[phil@desktop]$ /Users/phil/EC2/bin/ec2-describe-instances
 
RESERVATION	r-0dc57965	024439027432	default
INSTANCE	i-yourinstance	ami-youramiid	ec2-176-122-149-109.compute-1.amazonaws.com	domU-12-31-39-00-12-C1.compute-1.internal	running	phil-key-pair	0		m1.large	2009-02-13T23:51:11+0000	us-east-1c

Open the AWS Firewall ingress port 22

[phil@desktop]$ /Users/phil/EC2/bin/ec2-authorize default -p 22

Now you can ssh using your keypair as root!

[phil@desktop]$ ssh -i phil-key-pair root@ec2-176-122-149-109.compute-1.amazonaws.com
 
The authenticity of host 'ec2-176-122-149-109.compute-1.amazonaws.com (174.129.149.109)' can't be established.
RSA key fingerprint is cb:77:33:4f:a0:62:c0:a6:c8:40:99:09:25:4f:5d:ef.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'ec2-174-129-149-109.compute-1.amazonaws.com,174.129.149.109' (RSA) to the list of known hosts.
 
[root@domU-11-33-39-00-12-C1 ~]$

To terminate the instance you can do the following use the describe instance command to find the i-id then do the below

[phil@desktop]$ /Users/phil/EC2/bin/ec2-terminate-instances i-yourinstance
INSTANCE	i-yourinstance	running	shutting-down

If you ever need to stop deregister and delete your AMI you can do the following

[phil@desktop]$ /Users/phil/EC2/bin/ec2-deregister ami-youramiid
 
[root@server bin]$ /Users/phil/EC2/bin/ec2-delete-bundle -b phils-amis -a yourkey -s yoursecretkey -m /opt/EC2/ami-centos5.3-64bit-base.manifest.xml
 
[phil@desktop]$ :>~/.bash_history

If you need to modify your image do the above two steps of deregistering and deleting your bundle in S3 as well as delete the files in /opt/EC2AMIFILES then you can remount the image to make your changes using the same commands you did before

 
[root@server]$ mount -o loop /opt/EC2AMIIMAGE/ami-centos5.3-64bit-base.img /mnt/ami-centos5.3-64bit-base
 
[root@server]$ mount -t proc none /mnt/ami-centos5.3-64bit-base/proc

After you remount the image you can modify your software and then re-bundle, re-upload, re-register your ami.

For help setting up your environment or things I may have left out please refer to the documentation at Amazon or write me a comment.

One last note make sure you turn your EC2 Instances off if your not using them they do cost money $ :P

Happy AMI building!

Also a great resource for free Realtime AWS uptime data is Systems Watch

105 Responses to “How to create an Amazon Elastic Compute Cloud EC2 Machine Image (AMI)”

  1. Hi,

    I followed the steps mentioned , exactly and I am glad to report that works perfectly fine today!

    Thanks alot!

    Deependra

  2. Marc says:

    I’m also curious about the kernel update to 2.6.18, and to generalize these instructions.

    Would this be the right modules to try: http://developer.amazonwebservices.com/connect/entry.jspa?externalID=1345

  3. Phil Chen says:

    Hi Marc,

    Yes you could use those modules.

  4. msu pluto says:

    These seem like great steps. Are there similar kind of steps / tutorial for Windows users? I am familiar with “unix”. It’s just that I do not have access to one right now. So, I would like to do all the above things on Windows to create an image

    Thanks!

  5. ea says:

    could i build an AMI using LFS?

    http://www.linuxfromscratch.org/

  6. Tena Sakai says:

    Hi,

    Thanks for your web page and instruction for generating centos based ami.
    I am looking at getssh and would you explain what the line below is doing?

    /usr/bin/curl -f http://169.254.169.254/latest/meta-data/public-keys/0/openssh-key > /tmp/my-key

    What machine is 169.254.269.254?

    Thank you.

  7. Phil Chen says:

    Hello Tena,

    169.254.0.0-169.254.255.255 is what IANA Automatic Private IP Addressing

    In Amazon Web Services case they use it for API calls to retrieve information about your instance on startup. This particular API call I use in getssh has to do with your SSH key to add to your authorized_keys

    Phil

  8. Tena Sakai says:

    Hi Phil,

    Thanks for your response.

    I would like to report a possible / typo on your page where you do the registration:
    $ ./ec2-register phils-amis/ami-centos5.3-64bit-base.manifest.xml

    When I issue the command similar to the above, it complains as to name is missing.
    With the current incarnation of ec2-register, it seems “-n a-name-4-my-ami” is required.

    Tena

  9. Tena Sakai says:

    Hi Phil,

    I don’t understand what the command below means:

    [phil@desktop]$ ./ec2-add-keypair phils-keypair-raw

    What’s phils-keypair-raw? And what’s the rest of the stuff (keypair + private key) in the panel? How is this related to ec2-add-keypair command?

    Please explain.

    Thank you.

  10. Phil Chen says:

    Tena,

    Check out:

    http://docs.amazonwebservices.com/AmazonEC2/dg/2006-10-01/CLTRG-create-keypair.html regarding the ec2-add-keypair.

    To be honest you can just use the AWS console for your key pair management.

  11. Troy says:

    Any chance someone can post a cent os AMI that’s ready to go? maybe just take out their SSH key or anything that’s private??

  12. Phil Chen says:

    Troy,

    See my blog post:
    http://www.philchen.com/2010/05/31/amazon-ec2-64bit-centos-5-3-base-public-ami-s
    I have created public versions in each region. The key for root is whatever you start the image with. Hope that helps.

  13. Tena Sakai says:

    Hi Phil,

    I have been successful creating centos 5.5 ami from your instruction and using the instance. Many thanks for your article. Thanks also for responses to my questions (and to others’s as well).

    May I suggest in the next incarnation of the post, you include s3fs? s3fs sounds like an excellent tool to make “permanent” file system out of S3. I think it is a bit complicated due to underlying/required components, fuse for instance. Maybe this is a bit beyond “it is left as student exercise” and requires a helping hand from professor Phil. :)

    Tena

  14. Tena Sakai says:

    Hi Phil,

    I want to run an instance and then have that instance launch more instances. To do so, I need to include at least ec2-run-instances and other ec2-bla-bla tools in my ami. Would you please comment as to how I go about this? I.e., Where would be a good place to copy these amazon tools? What pitfalls might there be?

    Thank you.

    Tena

  15. Phil Chen says:

    Hi Tena

    Thanks for the feedback Tena I will look into writing a post for s3fs or a topic that meets the same requirement. As for your other question.

    You can include the amazon EC2 API tools within your AMI, by starting an instance of the AMI you created then wget the api tools in something like /usr/local/ami-tools write a bash, perl, or whatever scripting language you desire to execute starting instances given whatever your requirement is and then follow my snapshot article to create a new AMI, bundling all this.

    I actually don’t recommend doing it this way though, because you will need to have your amazon security credentials (pem files) embedded in your AMI. This is not the best idea. I wouldn’t bundle AWS security info in an AMI ever. I would think creating a server maybe not cloud that runs a RESTful API service that you can call via a token authentication system which in turn fires up new EC2 Instances would be better. On this server you probably should run a HIDS like OSSEC.

    So the workflow would be that your current AMI has a script or daemon that runs looking for your criteria of starting EC2 instances, when the criteria is met then it makes a secure API call to a RESTful API service server you have centralized which is hardened and has EC2 API TOOL’s and starts whatever number of instances you would like.

    Just my take on it. I could be missing what your asking me though. Security is a concern so just be careful on where you put your credentials. I always to the command history -c whenever I do snapshotting also so that my credentials never get stored in the snapshot.

  16. nbecker says:

    How do I change this for fedora 13 x86_64?

    Most is pretty straightforward, but what do I do with

    Install precompiled modules supplied by Amazon, since the kernel modules installed by yum are not appropriate for the EC2 environment.

  17. kevin says:

    Hi Phil,

    Great work! Thanks so much for taking your time to write up this guide. This is very helpful!

    One question I have, since I only have a desktop (installed centos 5.5) at home. Does hardware matter at all? Do I need a real 4u server to create an ami?

    Thanks!

    K

  18. Phil Chen says:

    Hi Kevin, you should be fine with using your CentOS 5.5 desktop build to build your AMI with my instructions. The only thing you need to be aware of is if you are using a 32bit or 64bit desktop environment. Using my method if you have a 32bit desktop you can only build the 32bit AMI and a 64bit desktop will allow you to build a 64bit AMI. I have blurbs for either, also. Having a 4u chassis doesn’t matter its really the OS and architecture that does.

  19. kevin says:

    AWESOME!!! This is going to be my thanksgiving project!

    Have a great turkey! Thanks again, Phil.

    K.

  20. Tena Sakai says:

    Hello Phil,

    I was wondering if you would show us mere motals how to build EBS based ami…
    Thank you.

    Tena Sakai

  21. Phil Chen says:

    Kevin,

    You have a great thanksgiving too. And good luck on your EC2 project I am sure it will turn out great! Also Kevin if you decide to build a 64bit AMI you will need to launch at minimum a large EC2 instance when done, if you are using 32bit AMI you can use small and up.

  22. Phil Chen says:

    Hi Tena,

    I have been so busy I have totally neglected blogging :-/ but this holiday I think I can start eeking out some time for more how to’s! Thank you for the feedback, I think a EBS based AMI would be a great post.

  23. Jason Howk says:

    Just a quick note that I didn’t see mentioned elsewhere. Any yum.conf file will, by default, look at /etc/yum.d/repos as well, so in effect your using what you’ve created plus what’s already defined on the system. Normally it may not be a big deal, but if you add a:

    reposdir=

    to the yum-ami.conf file you can make sure that only your custom yum.conf file is used instead of any system specific repos.

    Great post!

  24. Phil Chen says:

    Thanks Jason for that info, good to know. Glad you like the post.

  25. Tena Sakai says:

    Greetings Phil,

    I have emulated your post and generated an ami, which is working fine, but it doesn’t have c compiler. I would like to build another ami with compilers (including fortran). Can this be done by adding lines to yum-ami.conf, which in your example, resides in /opt/EC2YUM/ directory? Would you mind showing me what lines that would be?

    Thank you.

    Tena Sakai

  26. Tena Sakai says:

    Hi Phil,

    Please ignore my previous post. There was no need to do anything to yum-ami.con file. I was able to run yum commands on the running EC2 instance and then snapshot (thanks for your other web page) the image.

    Thank you.

    Tena Sakai

  27. Questionnaire says:

    Hi guys, I am new to this concept and would like to learn
    Can any1 please comment here
    What is an instance ? Does it mean SERVER ?
    and why do we take snapshots of instance ? What purpose does a snapshot serve ?

  28. Vijay says:

    Hi, guys here seem to be Pros working on Amazon cloud computing. what is the best place to get training on Amazon cloud computing? Thanks

  29. Roy Reiss says:

    Hi Phil,

    First thank you for the post. It is by far the best and most practical and informative guide I’ve seen around.

    I’ve searched around in the aws docs, but can’t find informative or practical links / downloads about the EC2 kernel modules. Where did you get the ones you used for this article?

    Thanks!

  30. Phil Chen says:

    Maida,

    http://www.amazon.com/Host-Your-Web-Site-Cloud/dp/0980576830 is a good book that recently came out to start with. Other then that just check out all the blogs and give it a whirl.

  31. Phil Chen says:

    Hi Roy,

    Glad you found the article helpful.

    http://alestic.com/2008/05/kernel-modules-2-6-21 is a good article on kernel modules.

  32. nicolethomson says:

    Hi

    So now i uploaded the files to S3, but i can only see it as filename.00 filename.01. till filename.51, how to combine them as .img file now?

    i did it partially through ec2- tool from console, and through upload link at aws manage link.

  33. Yogesh says:

    Its very useful for the beginner.

    Magento Development Company

  34. Phil Chen says:

    Nicole,

    The manifest file is the way all the individual files come together. You should see that file at the end of the different segmented files.

    Yogesh,

    Your welcome

  35. rahul says:

    Phil,

    Thanks for the great site.I have a query regarding installing gcc in the image i am creating.I had followed your steps and had registered an image in EC2.When i tried to install php from there,the gcc was missing.please let me know how to install gcc.

    Note: I am installing the OS my mounting it in any linux directory and pointing my YUM conf to that directory.

  36. Shah says:

    Phil,

    Thanks a lot for this great document. I was successfully create EC2 image and placed on s3. Can I discuss some other issue related to EC2 image bundling. Recently we got an instance –> created snapshot –> Now it seems to be placed in EBS. I am looking to bundle this instance on S3 bucket but when I try to do so, it throws “ERROR: Can’t access instance metadata. If you are not bundling on an EC2 instance use –no-inherit.” error :( . I tried to follow Amazon Ec2 forum and couldn’t get anything. Could you please suggest?

    Thanks,
    Shah

  37. David says:

    Phil

    Thanks for the practical help on creating EC2 AMIs. I have been following your article, but for an m1.small Redhat 32-bit instance. When I get to the creation of the 10GB file to hold the OS files I get a message saying I’ve run out of space:

    [root@server]$ dd if=/dev/zero of=/opt/EC2AMIIMAGE/ami-rhel6.1-32bit-base bs=1M count=10240
    dd: writing `/opt/EC2AMIIMAGE/ami-rhel6.1-32bit-base': No space left on device
    4225+0 records in
    4224+0 records out
    4429357056 bytes (4.4 GB) copied, 233.488 s, 19.0 MB/s

    When I check the amount of available disk with “df -h” I get

    [root@server]$ df -h
    Filesystem Size Used Avail Use% Mounted on
    /dev/xvde1 5.7G 5.7G 0 100% /
    none 837M 0 837M 0% /dev/shm

    Do you know how to fix this problem.

    Thanks
    David

  38. Phil Chen says:

    Hi David,

    You could try making the file smaller like 5G say:

    dd if=/dev/zero of=/opt/EC2AMIIMAGE/ami-rhel6.1-32bit-base bs=1M count=5120

    Or you could build your AMI from a machine with more disk space if you need more disk.

  39. Sammy says:

    Really nice post. I was wondering if there is any way you can show how top create EBS backed ami instead of the instance store.

  40. Earnest Paul says:

    Hi,

    we have few instances in EC2. I need to save it in EBS. Can you please guide me.

    Thanks
    Earnest paul

  41. Nick says:

    This is great and has really helped me out, one thing that would be very useful remains, would it be possible to include LVM filesystems in this image?

  42. Ameya says:

    Hi Phil,

    Its Great article. but right now i’m using Cetos6.2-32bit version as. & so far its woked gr8 for me bt hav stucked while installing Java to the image!!! Please help me in that.

    if i use this commad — “-/usr/sbin/chroot /mnt/ami-centos6.2-32bit-base ./jre-6u12-linux-x64.bin”
    it gives me error as — “/usr/sbin/chroot: failed to run command `./jre-6u12-linux-x86.bin': No such file or directory”

    & even i try to install java manually like u said via other command — “/usr/sbin/chroot /mnt/ami-centos6.2-32bit-base yum install jdk-1.6″
    it throws the error as– “http://ftp.iitm.ac.in/centos/6.2/os/i386/repodata/repomd.xml: [Errno 14] PYCURL ERROR 6 – “Couldn’t resolve host ‘ftp.iitm.ac.in'”
    Trying other mirror.”
    rather for every dependancy it thowing dis error — “ERROR 6 – “Couldn’t resolve host ‘ftp.iitm.ac.in'”
    Trying other mirror.”

    So please help me in that & possibly create d othr guide for newer versions of it!!
    Thanks phil.. :)

  43. Phil Chen says:

    For anyone who is having issues or wants to see the EBS backed build version of this please see my latest blog: http://www.philchen.com/2012/04/30/how-to-create-an-amazon-elastic-compute-cloud-ec2-machine-image-ami-centos-6-s3-backed-or-ebs-backed

    Thanks

  44. Geetika says:

    Hi Phil,

    I am new to AWS as well to Linux and I am trying to make a CentOS 5.8 AMI with MySQL, Tomcat and Jasper Report Server installed in the image. But installing MySQL is throwing error for error 2002 /var/lib/mysql/mysql.sock not found. My question is what kind of configuration and settings are required for MySQL to run on Image file. How to test it and how to configure it?

    Any input will be helpful.

    Thanks

  45. David says:

    Hi,

    1. I have installed slackware14.0 (64bit) in my local machine.

    2. I have created the 10 gb image space in slackware machine using below command.
    (dd if=/dev/zero of=slack14.img bs=1M count=10075). and mount the image in slack14.img.
    mount -o loop slack14.img /mnt/slack1464.

    3. I have format the image (slack14.img)

    4. I have installed the custom package through ruby script. The custom package for
    installed without any error.

    After that While login the mounting image (/mnt/slack1464).

    root@slack1464bit:~# chroot /mnt/slack1464
    chroot: failed to run command ‘/bin/bash’: No such file or directory
    root@slack1464bit:~#

    earlier I have created the .img image in (slackware13.1 & 13.37) without any error.

    But I am getting the error in Slackware14.0 64bit only.

    Thanks for advance.

    BY
    DAVID

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