Q:

EC2 DNS servers

DNS servers that are pre-configured on EC2 instances seem to be only: 172.16.0.23
Does anyone know if thats a dedicated DNS VIP for a specific region?  Should we add more DNS servers in for fault tolerance?

A:

I've never felt the need for anything else.
ec2-user@ip-10-112-39-42:~$ cat /etc/resolv.conf 
nameserver 172.16.0.23
domain ec2.internal
search ec2.internal
ec2-user@ip-10-112-39-42:~$

Feel free to change it if you want, though be aware that external DNS servers won't be able to resolve ec2.internal addresses.

