Take the tour ×  I'm trying to set up NAT on a windows server
2008 r2 instance inside a VPC on AWS.  I've got two windows
boxes, A and B  A has two network interfaces, one with an EIP
attached and can connect to the internet fine.  B has its
default gateway set to the private IP of As 2nd NIC (configured
in RRAS as the private NIC)  All NICs are in a security group
with all ports open.  I can RDP on to A, and from A to B, but A
and B can't ping each other, and B can't route any traffic
through A.  Tracerts timeout on every hop (they dont even hit B)
Any idea whats going wrong?   share|improve this question add
comment  1 Answer  I needed to disable source/dest check on A's
2nd interface.  Docs only say to do it on the instance. grrr
share|improve this answer I set up the NAT instance, but I can't
ping instances inside my public or my private subnets. How did
you disable source/dest on 2nd interface? –  Aymeric Gaurat-
Apelli Mar 26 at 4:20 add comment  Your Answer