An in-house ACK plugin that enforces Kubernetes NetworkPolicy rules on pod network traffic.
Introduction
Poseidon is an ACK add-on that implements the Kubernetes NetworkPolicy API.
Port matrix
The Poseidon controller is deployed on the managed side of the cluster and uses managed security groups.
Port | Function |
TCP/9082 | The listening port for the Poseidon controller. The Poseidon Agent needs to connect to the controller on this port to use NetworkPolicy and TrafficPolicy. |
Usage
To use network policies in ACK Serverless clusters, see Use network policies.
Limitations
NetworkPolicy is supported only in ACK Serverless clusters, on ECI in ACK clusters, and on ACS CPU instances. IPv4 only.
TrafficPolicy is supported only on ACS instances in ACK clusters and in ACS clusters. IPv4 only.
ACK GlobalNetworkPolicy is supported only on ECS instances in ACK clusters. Requires the Terway network plugin with NetworkPolicy enabled.
Changelog
June 2026
Version | Date | Description | Impact |
v0.8.0 | June 10, 2026 | Note This version is in a phased rollout.
| Non-breaking change. |
May 2026
Version | Date | Description | Impact |
v0.7.6 | May 22, 2026 |
| Non-breaking change. |
April 2026
Version | Date | Description | Impact |
v0.7.5 | April 22, 2026 |
| Non-breaking change. |
v0.7.4 | April 22, 2026 | Fixed an issue with TrafficPolicy rule synchronization. | Non-breaking change. |
v0.7.3 | April 17, 2026 |
| Non-breaking change. |
v0.7.1 | April 9, 2026 | Added support for TrafficPolicy in ECS node pools. | Non-breaking change. |
March 2026
Version | Date | Description | Impact |
v0.7.0 | March 26, 2026 | Added support for TrafficPolicy. | Non-breaking change. |
July 2024
Version | Date | Description | Impact |
v0.5.2 | July 29, 2024 | Fixed a compatibility issue with ACK Serverless clusters. | Non-breaking change. |
v0.5.1 | July 9, 2024 | Fixed an issue where the namespace selector might not take effect. | Non-breaking change. |
v0.5.0 | July 1, 2024 | Added support for ACK NetworkPolicy. | Non-breaking change. |
September 2023
Version | Date | Description | Impact |
v0.3.0 | September 8, 2023 | Added support for named ports in NetworkPolicy. | Non-breaking change. |
July 2023
Version | Date | Description | Impact |
v0.1.0 | July 6, 2023 | Added support for NetworkPolicy in ACK Serverless clusters. | Non-breaking change. |