Retrieves EC2 DNS by instance name and opens SSH

ec2-ssh.sh

#!/bin/bash
set -e

command -v aws >/dev/null 2>&1 || { echo >&2 "AWS CLI required. Please install from https://docs.aws.amazon.com/cli/latest/userguide/cli-chap-install.html"; exit 1; }

# get the name of EC2 instance from 1st argument
if [ -z "$1" ]
then
    echo "Instance name is required"
    exit 1
else
    NAME=$1
fi

# get the 2nd optional argument for path of key
if [ -z "$2" ]
then
    PRIVATE="/home/jenya/.ssh/id_rsa"
else
    PRIVATE=$2
fi

# validate private key file exists
if [ ! -f $PRIVATE ]; then
    echo "No file with private key found at '${PRIVATE}'"
    exit 1
fi

printf "Getting DNS name of ${NAME}..."
DNS=$(aws ec2 describe-instances --filters 'Name=tag:Name,Values='${NAME} --query 'Reservations[*].Instances[*].[PublicDnsName]' --output text)

# validate that instance was found for provided name
if [ -z "$DNS" ]
then
    printf "\nNo instance found with name '${NAME}'\n"
    exit 1
else
    echo " '${DNS}'"
fi

# the actual SSH to the instance
ssh -i ${PRIVATE} ubuntu@${DNS}
exit 0