Public NAT Instance

A Public NAT instance on GreenNode is a networking service that allows instances in a private subnet to communicate with the internet while preventing inbound traffic from the internet to those instances.

Public NAT Instance V2 is the new generation of the service. New Public NAT instances are created as V2 by default; existing V1 instances continue to operate normally.

What's new in V2

Highly available

V2 runs as a redundant pair (active/standby) with automatic failover. If one node fails, traffic continues through the other node with no action required, eliminating the single point of failure that existed in V1.

Automatic routing

In V1, you had to log in to each VM and manually add a route to the NAT gateway. In V2, GreenNode automatically adds the default route to your VPC route table when the NAT is created, so every instance reaches the internet through the NAT — no per-VM configuration is required.

Works across the whole VPC

In V1, only VMs on the same subnet as the NAT could route through it. In V2, any VM in the same VPC (the entire /16) can reach the internet through the NAT — not just the NAT's subnet.

How to tell V1 from V2

In the Public NAT list, look at the HA column: HA = Yes means the NAT is V2 (highly available); HA = No means it is a V1 NAT.

The HA column on the Public NAT list: Yes = V2, No = V1

Feature summary

Capability	V1 (legacy)	V2
High availability / failover	Single node	Redundant pair, automatic failover
Which VMs can use the NAT	Same subnet only (/24)	Entire VPC (/16)
Routing for your VMs	Manual, per-VM	Automatic, added to the VPC route table
Public interface	Created automatically	Created automatically
Default allowed services (from your VPC)	DNS, HTTP, HTTPS, ICMP	DNS, HTTP, HTTPS, ICMP
Add / remove inbound rules	Yes	Yes