From 028e3ceb490673a52a3232324c25ded20800c584 Mon Sep 17 00:00:00 2001 From: David Nuzik Date: Tue, 31 Mar 2020 13:54:17 -0700 Subject: [PATCH] Update installation-requirements networking section - Addresses comment around node-requirements page (now installation-requirements) in issue https://github.com/rancher/k3s/issues/1031 - Accompslishes this by adding a table to list ports, we actually took from /rancher/v2.x/en/installation/requirements/ports networking section so both guides are in alignment --- .../installation-requirements/_index.md | 16 ++++++++++++++-- 1 file changed, 14 insertions(+), 2 deletions(-) diff --git a/content/k3s/latest/en/installation/installation-requirements/_index.md b/content/k3s/latest/en/installation/installation-requirements/_index.md index 13da6c3d7ce..44e9bf5008f 100644 --- a/content/k3s/latest/en/installation/installation-requirements/_index.md +++ b/content/k3s/latest/en/installation/installation-requirements/_index.md @@ -37,12 +37,24 @@ K3s performance depends on the performance of the database. To ensure optimal sp ## Networking -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 (Flannel VXLAN). If you do not use Flannel and provide your own custom CNI, then port 8472 is not needed by K3s. 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. +The K3s server needs port 6443 to be accessible by the nodes. -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 disabled access to port 8472. +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. + +
Inbound Rules for Rancher Server Nodes
+ +| Protocol | Port | Source | Description +|-----|-----|----------------|---| +| 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 + +Typically all outbound traffic is allowed. + ## Large Clusters Hardware requirements are based on the size of your K3s cluster. For production and large clusters, we recommend using a high-availability setup with an external database. The following options are recommended for the external database in production: