# Default behavior for Nodeport service

**URL:** <https://discuss.kubernetes.io/t/default-behavior-for-nodeport-service/22445>\
**Category:** General Discussions\
**Created:** [December 27, 2022, 1:27am UTC](https://discuss.kubernetes.io/t/default-behavior-for-nodeport-service/22445 "2022-12-27T01:27:46Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![Zeeshannetwork](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/zeeshannetwork/32/11458_2.png) [@Zeeshannetwork](https://discuss.kubernetes.io/u/Zeeshannetwork)\
**Post date:** [December 27, 2022, 1:27am UTC](https://discuss.kubernetes.io/t/default-behavior-for-nodeport-service/22445/1 "2022-12-27T01:27:46Z")

</div>

I am new to K8, currently learning node port service. I have three node cluster with node network on 192..168.1.0/24:  
N1: 192.168.1.10  
N2: 192.168.1.20  
Master: 192.168.1.40  
In my set up, I have NGINX app that is running on port 80 on pod2, on node2. I have exposed NGINX service using node port service on port 30000.  
When I browse the service externally using 192.168.1.10:3000, I noticed following:

1. Node1 , starts a new TCP session sourced from its flannel.1 IP, destined to POD2 's IP.

There is no NATTING on Node1. But then I read following:

> **[Using Source IP](https://kubernetes.io/docs/tutorials/services/source-ip/)**
>
> Applications running in a Kubernetes cluster find and communicate with each other, and the outside world, through the Service abstraction. This document explains what happens to the source IP of packets sent to different types of Services, and how...

**Packets sent to Services with [`Type=NodePort`] are source NAT’d by default.**

I have not changed any setting on my ubuntu for IP tables.  
Much appreciated!!!

### Cluster information:

Kubernetes version: v1.26.0  
Cloud being used: Bare metal  
Installation method: kubeadm init  
Host OS: Ubuntu 18.04 LTS  
CNI and version: 10-flannel.conflist  
CRI and version: containerd://1.6.14

---

<div class="post-metadata">

**Author:** ![thockin](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/thockin/32/2457_2.png) [@thockin](https://discuss.kubernetes.io/u/thockin)\
**Post date:** [December 27, 2022, 4:20am UTC](https://discuss.kubernetes.io/t/default-behavior-for-nodeport-service/22445/2 "2022-12-27T04:20:21Z")

</div>

Pod to pod traffic should not be NAT. It doesn’t say anything about services or node ports.