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AWS pcs documentation change

Service: pcs · 2026-07-04 · Documentation low

File: pcs/latest/userguide/working-with_networking_sg.md

Summary

Corrected port range documentation for srun to reference OS ephemeral ports and custom settings.

Security assessment

This is a documentation correction about port usage with no security implications. No security vulnerabilities or features are mentioned.

Diff

diff --git a/pcs/latest/userguide/working-with_networking_sg.md b/pcs/latest/userguide/working-with_networking_sg.md
index 220bbaf20..ea2cefa4c 100644
--- a//pcs/latest/userguide/working-with_networking_sg.md
+++ b//pcs/latest/userguide/working-with_networking_sg.md
@@ -62 +62 @@ The security group attached to your compute nodes must allow the following ports
-  * 60001–63000 – inbound and outbound connections between node group instances to support `srun`
+  * AWS PCS doesn't set a fixed `srun` port range by default, so `srun` uses the operating system's ephemeral ports (on Linux, 32768–60999) unless you pin it with the [SrunPortRange](https://slurm.schedmd.com/slurm.conf.html#OPT_SrunPortRange) custom Slurm setting (for example, `SrunPortRange=60001-63000`) and allow that range in your security group rules. See [Custom Slurm settings for AWS PCS clusters](./slurm-custom-settings-cluster.html).