website/docs/user-guide/connecting-to-applications-...

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kubectl port-forward forwards connections to a local port to a port on a pod. Its man page is available [here](/docs/user-guide/kubectl/kubectl_port-forward). Compared to [kubectl proxy](/docs/user-guide/accessing-the-cluster/#using-kubectl-proxy), `kubectl port-forward` is more generic as it can forward TCP traffic while `kubectl proxy` can only forward HTTP traffic. This guide demonstrates how to use `kubectl port-forward` to connect to a Redis database, which may be useful for database debugging.
## Creating a Redis master
```shell
$ kubectl create examples/redis/redis-master.yaml
pods/redis-master
```
wait until the Redis master pod is Running and Ready,
```shell
$ kubectl get pods
NAME READY STATUS RESTARTS AGE
redis-master 2/2 Running 0 41s
```
## Connecting to the Redis master[a]
The Redis master is listening on port 6379, to verify this,
```shell{% raw %}
$ kubectl get pods redis-master -t='{{(index (index .spec.containers 0).ports 0).containerPort}}{{"\n"}}'
6379{% endraw %}
```
then we forward the port 6379 on the local workstation to the port 6379 of pod redis-master,
```shell
$ kubectl port-forward redis-master 6379:6379
I0710 14:43:38.274550 3655 portforward.go:225] Forwarding from 127.0.0.1:6379 -> 6379
I0710 14:43:38.274797 3655 portforward.go:225] Forwarding from [::1]:6379 -> 6379
```
To verify the connection is successful, we run a redis-cli on the local workstation,
```shell
$ redis-cli
127.0.0.1:6379> ping
PONG
```
Now one can debug the database from the local workstation.