Longhorn Networking
Overview
This page documents the networking communication between components in the Longhorn system. Using this information, users can write Kubernetes NetworkPolicy to control the inbound/outbound traffic to/from Longhorn components. This helps to reduce the damage when a malicious pod breaks into the in-cluster network.
We have provided some NetworkPolicy example yamls at here. Note that depending on the deployed CNI, not all Kubernetes clusters support NetworkPolicy. See here for more detail.
Note: If you are writing network policies, please revisit this page before upgrading Longhorn to make the necessary adjustments to your network policies.
Longhorn Manager
Ingress:
| From | Port | Protocol |
|---|---|---|
Other Longhorn Manager | 9500 | TCP |
UI | 9500 | TCP |
Longhorn CSI plugin | 9500 | TCP |
Backup/Snapshot Recurring Job Pod | 9500 | TCP |
Longhorn Driver Deployer | 9500 | TCP |
Egress:
| To | Port | Protocol |
|---|---|---|
Other Longhorn Manager | 9500 | TCP |
Instance Manager | 8500; 8501 | TCP |
Backing Image Manager | 8000 | TCP |
Backing Image Data Source | 8000 | TCP |
External Backupstore | User defined | TCP |
Kubernetes API server | Kubernetes API server port | TCP |
UI
ingress:
Users defined
egress:
| To | Port | Protocol |
|---|---|---|
Longhorn Manager | 9500 | TCP |
Instance Manager
ingress
| From | Port | Protocol |
|---|---|---|
Longhorn Manager | 8500; 8501 | TCP |
Other Instance Manager | 10000-30000 | TCP |
Node in the Cluster | 3260 | TCP |
Backing Image Data Source | 10000-30000 | TCP |
egress:
| To | Port | Protocol |
|---|---|---|
Other Instance Manager | 10000-30000 | TCP |
Backing Image Data Source | 8002 | TCP |
External Backupstore | User defined | TCP |
Longhorn CSI plugin
ingress
None
egress:
| To | Port | Protocol |
|---|---|---|
Longhorn Manager | 9500 | TCP |
Additional Info
Longhorn CSI plugin pods communitate with CSI sidecar pods over the Unix Domain Socket at <Kuberlet-Directory>/plugins/driver.longhorn.io/csi.sock
CSI sidecar (csi-attacher, csi-provisioner, csi-resizer, csi-snapshotter)
ingress:
None
egress:
| To | Port | Protocol |
|---|---|---|
Kubernetes API server | Kubernetes API server port | TCP |
Additional Info
CSI sidecar pods communitate with Longhorn CSI plugin pods over the Unix Domain Socket at <Kuberlet-Directory>/plugins/driver.longhorn.io/csi.sock
Driver deployer
ingress:
None
egress:
| To | Port | Protocol |
|---|---|---|
Longhorn Manager | 9500 | TCP |
Kubernetes API server | Kubernetes API server port | TCP |
Conversion and Admission Webhook Server
ingress:
| From | Port | Protocol |
|---|---|---|
Webhook Server | 9443 | TCP |
NFS Recovery Backend Server
ingress:
| From | Port | Protocol |
|---|---|---|
Recovery Backend Server | 9600 | TCP |
Engine Image
ingress:
None
egress:
None
Backing Image Manager
ingress:
| From | Port | Protocol |
|---|---|---|
Longhorn Manager | 8000 | TCP |
Other Backing Image Manager | 30001-31000 | TCP |
egress:
| To | Port | Protocol |
|---|---|---|
Instance Manager | 10000-30000 | TCP |
Other Backing Image Manager | 30001-31000 | TCP |
Backing Image Data Source | 8000 | TCP |
Backing Image Data Source
ingress:
| From | Port | Protocol |
|---|---|---|
Longhorn Manager | 8000 | TCP |
Instance Manager | 8002 | TCP |
Backing Image Manager | 8000 | TCP |
egress:
| To | Port | Protocol |
|---|---|---|
Instance Manager | 10000-30000 | TCP |
User provided server IP to download the images from | user defined | TCP |
Share Manager
ingress
| From | Port | Protocol |
|---|---|---|
Node in the cluster | 2049 | TCP |
egress:
None
Backup/Snapshot Recurring Job Pod
ingress:
None
egress:
| To | Port | Protocol |
|---|---|---|
Longhorn Manager | 9500 | TCP |
Uninstaller
ingress:
None
egress:
| To | Port | Protocol |
|---|---|---|
Kubernetes API server | Kubernetes API server port | TCP |
Discover Proc Kubelet Cmdline
ingress:
None
egress:
None
Original GitHub issue: https://github.com/longhorn/longhorn/issues/1805
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