What is this about?

http://169.254.169.254/
ipv6 fd00:ec2::254

use this of ssrf, xxe ssrf etc rfi/lfi etc

IMDSv1

[ec2-user ~]$ curl http://169.254.169.254/latest/meta-data/    
ami-id
ami-launch-index
ami-manifest-path
block-device-mapping/
events/
hostname
iam/
instance-action
instance-id
instance-type
local-hostname
local-ipv4
mac
metrics/
network/
placement/
profile
public-hostname
public-ipv4
public-keys/
reservation-id
security-groups
services/

IMDSv2 ~~~http request [ec2-user ~]$ TOKEN=curl -X PUT "http://169.254.169.254/latest/api/token" -H "X-aws-ec2-metadata-token-ttl-seconds: 21600"
&& curl -H “X-aws-ec2-metadata-token: $TOKEN” -v http://169.254.169.254/latest/meta-data/
ami-id ami-launch-index ami-manifest-path block-device-mapping/ events/ hostname iam/ instance-action instance-id instance-life-cycle instance-type local-hostname local-ipv4 mac metrics/ network/ placement/ profile public-hostname public-ipv4 public-keys/ reservation-id security-groups services/ ~~~ src amazon