Oliver Legg olly
dialt0ne
/ get_aws_dns_ip.sh
Created
December 17, 2015 22:44
Get AmazonProvidedDNS IP address from the EC2 meta-data
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| MAC_ADDR=`curl -s http://169.254.169.254/latest/meta-data/mac` | |
| CIDR_FULL=`curl -s http://169.254.169.254/latest/meta-data/network/interfaces/macs/${MAC_ADDR}/vpc-ipv4-cidr-block` | |
| CIDR_BASE=`echo ${CIDR_FULL} | cut -d/ -f1 | cut -d\. -f1-3` | |
| LAST_OCTET=`echo ${CIDR_FULL} | cut -d/ -f1 | cut -d\. -f4` | |
| DNS_OCTET=`expr ${LAST_OCTET} + 2` | |
| DNS_IP="${CIDR_BASE}.${DNS_OCTET}" | |
| echo $DNS_IP |