# Blog: Kubernetes Networking Internals

**URL:** <https://discuss.kubernetes.io/t/blog-kubernetes-networking-internals/3766>\
**Category:** General Discussions\
**Tags:** k8s-blog\
**Created:** [December 6, 2018, 10:48am UTC](https://discuss.kubernetes.io/t/blog-kubernetes-networking-internals/3766 "2018-12-06T10:48:47Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![sagarnangare](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/sagarnangare/32/1760_2.png) [@sagarnangare](https://discuss.kubernetes.io/u/sagarnangare)\
**Post date:** [December 6, 2018, 10:48am UTC](https://discuss.kubernetes.io/t/blog-kubernetes-networking-internals/3766/1 "2018-12-06T10:48:48Z")

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Get an overview of Kubernetes networking internals from this article [https://blog.calsoftinc.com/2017/03/kubernetes-networking-internals.html](https://blog.calsoftinc.com/2017/03/kubernetes-networking-internals.html)

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**Author:** ![suman\_saurabh](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/suman_saurabh/32/4747_2.png) [@suman\_saurabh](https://discuss.kubernetes.io/u/suman_saurabh)\
**Post date:** [March 15, 2020, 5:32pm UTC](https://discuss.kubernetes.io/t/blog-kubernetes-networking-internals/3766/2 "2020-03-15T17:32:18Z")

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Some basics for Quick Checks

ip link  
ip link | grep ens3  
ip link show ens3  
arp node  
ip route show default  
netstat -nplt  
netstat -anp | grep etcd

ps -aux | grep kubelet  
ps -aux | grep kube-api  
ls /etc/cni/net.d/

kubectl logs weave -n kube-system  
kubectl logs -n kube-system

kubectl run test --restart=Never --image=busybox:1.28 --rm -it – nslookup nginx-resolver-service

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**Author:** ![khastation](https://avatars.discourse-cdn.com/v4/letter/k/c37758/32.png) [@khastation](https://discuss.kubernetes.io/u/khastation)\
**Post date:** [July 1, 2020, 9:28pm UTC](https://discuss.kubernetes.io/t/blog-kubernetes-networking-internals/3766/3 "2020-07-01T21:28:45Z")

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check current policy  
kubectl describe netpol

kubectl run --generator=run-pod/v1 test-np --image=busybox:1.28 --rm -it – sh  
nc -z -v -w 2 np-test-service 80

test if a service is up

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<div class="post-metadata">

**Author:** ![Jinhong\_Brejnholt](https://sea2.discourse-cdn.com/flex016/user_avatar/discuss.kubernetes.io/jinhong_brejnholt/32/6095_2.png) [@Jinhong\_Brejnholt](https://discuss.kubernetes.io/u/Jinhong_Brejnholt)\
**Post date:** [January 13, 2021, 8:45am UTC](https://discuss.kubernetes.io/t/blog-kubernetes-networking-internals/3766/4 "2021-01-13T08:45:02Z")

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Check process/service:  
netstat -plnt | grep PortNumber  
or  
lsof -i :PortNumber

Use systemctl to check/start/stop/disable/enable service:  
systemctl status serviceName