ajbrown

This file contains examples of using the AWS CLI to perform bootstrapping actions on EC2 instances through Userdata. These are useful in your terraform scripts to perform configuration that isn't natively supported.

Determine IP Address of EFS mount target

aws efs describe-mount-targets --file-system-id=fs-123456abcd | jq -r '.MountTargets[] | select(.SubnetId | contains("subnet-12345abcd")) | .IpAddress'

ajbrown

#!/usr/bin/env bash

# Deploy a new image to an ECS service by creating a new task revision 
# specifying a container repoository tag, and updating the service to use the new revision.
#
# Note: Your application's container MUST be the first container in the task revision.

#The tag to deploy.  Specify as the first cli argument
TAG=$1

ajbrown

<?php 
public function isLeader() {
    $isLeader = true;  // get my instance-id from the metadata service
    $instanceId = exec('curl http://169.254.169.254/latest/meta-data/instance-id');
    if (!empty($instanceId)) {
        $isLeader = false;
        $ec2 = \Aws\Ec2\Ec2Client::factory(['key' => AWS_ACCESS_KEY_ID, 'secret' => AWS_SECRET_KEY, 'region' => 'us-east-1']);
        $data = $ec2->describeInstances(array('InstanceIds' => [$instanceId]));
        if (!empty($data) && !empty($data['Reservations'])) {
            $tags = $data['Reservations'][0]['Instances'][0]['Tags'];

ajbrown

#!/usr/bin/env bash

totalMemKB=$(awk '/MemTotal:/ { print $2 }' /proc/meminfo)
usagePercent=70
let heapMB=$totalMemKB*$usagePercent/100/1024

JAV_OPTS="$JAVA_OPTS -Xmx${heapMB}M -Xms${heapMB}M"

ajbrown

Keybase proof

I hereby claim:

• I am ajbrown on github.
• I am adrianjbrown (https://keybase.io/adrianjbrown) on keybase.
• I have a public key ASASwbI7s2Xh6NiHcNPrdyoRmieDuNC6oSV8Inl8uPMVgwo

To claim this, I am signing this object:

ajbrown

#!/bin/sh
# Usage: setup_user.sh <username> <path-to-pub-key>
#
# Credit to TechRepublic.com for inspiration: 
USERNAME=$1
KEYPATH=$2

useradd -s /bin/bash -m $USERNAME
openssl rand -base64 8 | tee -a /home/$USERNAME/.password | passwd --stdin $USERNAME
chmod 600 /home/$USERNAME/.password

ajbrown

#!/usr/bin/env bash
#
# Add the security groups you want to allow the current IP address 
# SSH access to by updating the "groups" array below.  The user
# running the script must have the aws-cli installed and configured.
# Their credentials will be used for API calls, so access should be
# controlled that way.
#
# Note:  It's a good idea to clean up these security groups regularly.
# I prefer to have a security group that I can remove all ingress rules

ajbrown

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Sid": "Stmt1457967512000",
            "Effect": "Allow",
            "Action": [
                "s3:ListAllMyBuckets"
            ],
            "Resource": [

ajbrown

#!/bin/bash
# This script will ensure a device has a filesystem before mounting it to a given path.  
# It will only attempt to create the filesystem if one does not already exist on the device.
#
# AUTHOR: A.J. Brown <aj@ajbrown.org>

DEV='/dev/xvdf'
MOUNT_TO='/data'
FS='ext4'

ajbrown

curl -XPOST -d '{ "actions" : [ { "add" : { "index" : "events-1", "alias" : "events-write" } },{ "add" : { "index" : "events-1", "alias" : "events-read" } },{ "add" : { "index" : "audit-1", "alias" : "audit-write" } },{ "add" : { "index" : "audit-1", "alias" : "audit-read" } }]}' \
  -i http://user:Passw0rd@localhost:9200/_aliases