Port Requirements

import PortsIaasNodes from '@site/src/components/PortsIaasNodes' import PortsCustomNodes from '@site/src/components/PortsCustomNodes' import PortsImportedHosted from '@site/src/components/PortsImportedHosted'

To operate properly, Rancher requires a number of ports to be open on Rancher nodes and on downstream Kubernetes cluster nodes.

Rancher Nodes

The following table lists the ports that need to be open to and from nodes that are running the Rancher server.

The port requirements differ based on the Rancher server architecture.

Rancher can be installed on any Kubernetes cluster. For Rancher installs on a K3s, RKE, or RKE2 Kubernetes cluster, refer to the tabs below. For other Kubernetes distributions, refer to the distribution’s documentation for the port requirements for cluster nodes.

Notes:

  • Rancher nodes may also require additional outbound access for any external authentication provider which is configured (LDAP for example).

  • Kubernetes recommends TCP 30000-32767 for node port services.

  • For firewalls, traffic may need to be enabled within the cluster and pod CIDR.

  • Rancher nodes may also need outbound access to an external S3 location which is used for storing cluster backups (Minio for example).

Ports for Rancher Server Nodes on SUSE® Rancher Prime: K3s

Click to expand

The K3s server needs port 6443 to be accessible by the nodes.

The nodes need to be able to reach other nodes over UDP port 8472 when Flannel VXLAN is used. The node should not listen on any other port. K3s uses reverse tunneling such that the nodes make outbound connections to the server and all kubelet traffic runs through that tunnel. However, if you do not use Flannel and provide your own custom CNI, then port 8472 is not needed by K3s.

If you wish to utilize the metrics server, you will need to open port 10250 on each node.

Important:

The VXLAN port on nodes should not be exposed to the world as it opens up your cluster network to be accessed by anyone. Run your nodes behind a firewall/security group that disables access to port 8472.

The following tables break down the port requirements for inbound and outbound traffic:

Table 1. Inbound Rules for Rancher Server Nodes
Protocol Port Source Description

TCP

80

Load balancer/proxy that does external SSL termination

Rancher UI/API when external SSL termination is used

TCP

443

<ul><li>server nodes</li><li>agent nodes</li><li>hosted/registered Kubernetes</li><li>any source that needs to be able to use the Rancher UI or API</li></ul>

Rancher agent, Rancher UI/API, kubectl

TCP

6443

K3s server nodes

Kubernetes API

UDP

8472

K3s server and agent nodes

Required only for Flannel VXLAN.

TCP

10250

K3s server and agent nodes

kubelet
Table 2. Outbound Rules for Rancher Nodes
Protocol Port Destination Description

TCP

22

Any node IP from a node created using Node Driver

SSH provisioning of nodes using Node Driver

TCP

443

git.rancher.io

Rancher catalog

TCP

2376

Any node IP from a node created using Node driver

Docker daemon TLS port used by Docker Machine

TCP

6443

Hosted/Imported Kubernetes API

Kubernetes API server

Ports for Rancher Server Nodes on RKE

Click to expand

Typically Rancher is installed on three RKE nodes that all have the etcd, control plane and worker roles.

The following tables break down the port requirements for traffic between the Rancher nodes:

Table 3. Rules for traffic between Rancher nodes
Protocol Port Description

TCP

443

Rancher agents

TCP

2379

etcd client requests

TCP

2380

etcd peer communication

TCP

6443

Kubernetes apiserver

TCP

8443

Nginx Ingress’s Validating Webhook

UDP

8472

Canal/Flannel VXLAN overlay networking

TCP

9099

Canal/Flannel livenessProbe/readinessProbe

TCP

10250

Metrics server communication with all nodes

TCP

10254

Ingress controller livenessProbe/readinessProbe

The following tables break down the port requirements for inbound and outbound traffic:

Table 4. Inbound Rules for Rancher Nodes
Protocol Port Source Description

TCP

22

RKE CLI

SSH provisioning of node by RKE

TCP

80

Load Balancer/Reverse Proxy

HTTP traffic to Rancher UI/API

TCP

443

<ul><li>Load Balancer/Reverse Proxy</li><li>IPs of all cluster nodes and other API/UI clients</li></ul>

HTTPS traffic to Rancher UI/API

TCP

6443

Kubernetes API clients

HTTPS traffic to Kubernetes API
Table 5. Outbound Rules for Rancher Nodes
Protocol Port Destination Description

TCP

443

git.rancher.io

Rancher catalog

TCP

22

Any node created using a node driver

SSH provisioning of node by node driver

TCP

2376

Any node created using a node driver

Docker daemon TLS port used by node driver

TCP

6443

Hosted/Imported Kubernetes API

Kubernetes API server

TCP

Provider dependent

Port of the Kubernetes API endpoint in hosted cluster

Kubernetes API

Ports for Rancher Server Nodes on SUSE® Rancher Prime: RKE2

Click to expand

The RKE2 server needs port 6443 and 9345 to be accessible by other nodes in the cluster.

All nodes need to be able to reach other nodes over UDP port 8472 when Flannel VXLAN is used.

If you wish to utilize the metrics server, you will need to open port 10250 on each node.

Important:

The VXLAN port on nodes should not be exposed to the world as it opens up your cluster network to be accessed by anyone. Run your nodes behind a firewall/security group that disables access to port 8472.
Table 6. Inbound Rules for RKE2 Server Nodes
Protocol Port Source Description

TCP

9345

RKE2 server and agent nodes

Node registration. Port should be open on all server nodes to all other nodes in the cluster.

TCP

6443

RKE2 agent nodes

Kubernetes API

UDP

8472

RKE2 server and agent nodes

Required only for Flannel VXLAN

TCP

10250

RKE2 server and agent nodes

kubelet

TCP

2379

RKE2 server nodes

etcd client port

TCP

2380

RKE2 server nodes

etcd peer port

TCP

30000-32767

RKE2 server and agent nodes

NodePort port range. Can use TCP or UDP.

TCP

5473

Calico-node pod connecting to typha pod

Required when deploying with Calico

HTTP

80

Load balancer/proxy that does external SSL termination

Rancher UI/API when external SSL termination is used

HTTPS

443

<ul><li>hosted/registered Kubernetes</li><li>any source that needs to be able to use the Rancher UI or API</li></ul>

Rancher agent, Rancher UI/API, kubectl. Not needed if you have a load balancer doing TLS termination.

Typically all outbound traffic is allowed.

Ports for Rancher Server in Docker

Click to expand

The following tables break down the port requirements for Rancher nodes, for inbound and outbound traffic:

Table 7. Inbound Rules for Rancher Node
Protocol Port Source Description

TCP

80

Load balancer/proxy that does external SSL termination

Rancher UI/API when external SSL termination is used

TCP

443

<ul><li>hosted/registered Kubernetes</li><li>any source that needs to be able to use the Rancher UI or API</li></ul>

Rancher agent, Rancher UI/API, kubectl
Table 8. Outbound Rules for Rancher Node
Protocol Port Source Description

TCP

22

Any node IP from a node created using Node Driver

SSH provisioning of nodes using Node Driver

TCP

443

git.rancher.io

Rancher catalog

TCP

2376

Any node IP from a node created using a node driver

Docker daemon TLS port used by Docker Machine

TCP

6443

Hosted/Imported Kubernetes API

Kubernetes API server

Downstream Kubernetes Cluster Nodes

Downstream Kubernetes clusters run your apps and services. This section describes what ports need to be opened on the nodes in downstream clusters so that Rancher can communicate with them.

The port requirements differ depending on how the downstream cluster was launched. Each of the tabs below list the ports that need to be opened for different cluster types.

The following diagram depicts the ports that are opened for each cluster type.

Basic Port Requirements
Figure 1. Port Requirements for the Rancher Management Plane

If security isn’t a large concern and you’re okay with opening a few additional ports, you can use the table in Commonly Used Ports as your port reference instead of the comprehensive tables below.

Ports for SUSE® Virtualization Clusters

Refer to the Harvester Integration Overview for more information on Harvester port requirements.

Ports for Rancher Launched Kubernetes Clusters using Node Pools

Click to expand

The following table depicts the port requirements for Rancher Launched Kubernetes with nodes created in an Infrastructure Provider.

The required ports are automatically opened by Rancher during creation of clusters in cloud providers like Amazon EC2 or DigitalOcean.

Ports for Rancher Launched Kubernetes Clusters using Custom Nodes

Click to expand

The following table depicts the port requirements for Rancher Launched Kubernetes with Custom Nodes.

Ports for Hosted Kubernetes Clusters

Click to expand

The following table depicts the port requirements for hosted clusters.

Ports for Registered Clusters

Registered clusters were called imported clusters before Rancher v2.5.
Click to expand

The following table depicts the port requirements for registered clusters.

Other Port Considerations

Commonly Used Ports

These ports are typically opened on your Kubernetes nodes, regardless of what type of cluster it is.

Protocol Port Description

TCP

22

Node driver SSH provisioning

TCP

179

Calico BGP Port

TCP

2376

Node driver Docker daemon TLS port

TCP

2379

etcd client requests

TCP

2380

etcd peer communication

UDP

8472

Canal/Flannel VXLAN overlay networking

UDP

4789

Flannel VXLAN overlay networking on Windows cluster

TCP

8443

Rancher webhook

TCP

9099

Canal/Flannel livenessProbe/readinessProbe

TCP

9443

Rancher webhook

TCP

9796

Default port required by Monitoring to scrape metrics from Linux and Windows node-exporters

TCP

6783

Weave Port

UDP

6783-6784

Weave UDP Ports

TCP

10250

Metrics server communication with all nodes API

TCP

10254

Ingress controller livenessProbe/readinessProbe

TCP/UDP

30000-32767

NodePort port range

Local Node Traffic

Ports marked as local traffic (i.e., 9099 TCP) in the above requirements are used for Kubernetes healthchecks (livenessProbe andreadinessProbe). These healthchecks are executed on the node itself. In most cloud environments, this local traffic is allowed by default.

However, this traffic may be blocked when:

  • You have applied strict host firewall policies on the node.

  • You are using nodes that have multiple interfaces (multihomed).

In these cases, you have to explicitly allow this traffic in your host firewall, or in case of public/private cloud hosted machines (i.e. AWS or OpenStack), in your security group configuration. Keep in mind that when using a security group as source or destination in your security group, explicitly opening ports only applies to the private interface of the nodes / instances.

Rancher AWS EC2 Security Group

When using the AWS EC2 node driver to provision cluster nodes in Rancher, you can choose to let Rancher create a security group called rancher-nodes. The following rules are automatically added to this security group.

Type Protocol Port Range Source/Destination Rule Type

SSH

TCP

22

0.0.0.0/0

Inbound

HTTP

TCP

80

0.0.0.0/0

Inbound

Custom TCP Rule

TCP

443

0.0.0.0/0

Inbound

Custom TCP Rule

TCP

2376

0.0.0.0/0

Inbound

Custom TCP Rule

TCP

2379-2380

sg-xxx (rancher-nodes)

Inbound

Custom UDP Rule

UDP

4789

sg-xxx (rancher-nodes)

Inbound

Custom TCP Rule

TCP

6443

0.0.0.0/0

Inbound

Custom UDP Rule

UDP

8472

sg-xxx (rancher-nodes)

Inbound

Custom TCP Rule

TCP

10250-10252

sg-xxx (rancher-nodes)

Inbound

Custom TCP Rule

TCP

10256

sg-xxx (rancher-nodes)

Inbound

Custom TCP Rule

TCP

30000-32767

0.0.0.0/0

Inbound

Custom UDP Rule

UDP

30000-32767

0.0.0.0/0

Inbound

All traffic

All

All

0.0.0.0/0

Outbound

Opening SUSE Linux Ports

SUSE Linux may have a firewall that blocks all ports by default. To open the ports needed for adding the host to a custom cluster,

  • SLES 15 / openSUSE Leap 15

  • SLES 12 / openSUSE Leap 42

  1. SSH into the instance.

  2. Start YaST in text mode:

     sudo yast2

  3. Navigate to Security and Users > Firewall > Zones:public > Ports. To navigate within the interface, follow these instructions.

  4. To open the required ports, enter them into the TCP Ports and UDP Ports fields. In this example, ports 9796 and 10250 are also opened for monitoring. The resulting fields should look similar to the following:

     TCP Ports
 22, 80, 443, 2376, 2379, 2380, 6443, 9099, 9796, 10250, 10254, 30000-32767
 UDP Ports
 8472, 30000-32767

  5. When all required ports are enter, select Accept.

  1. SSH into the instance.

  2. Edit /etc/sysconfig/SuSEfirewall2 and open the required ports. In this example, ports 9796 and 10250 are also opened for monitoring:

     FW_SERVICES_EXT_TCP="22 80 443 2376 2379 2380 6443 9099 9796 10250 10254 30000:32767"
 FW_SERVICES_EXT_UDP="8472 30000:32767"
 FW_ROUTE=yes

  3. Restart the firewall with the new ports:

     SuSEfirewall2

Result: The node has the open ports required to be added to a custom cluster.