Network Policy¶
This page describes the network and firewall configuration on the Xtra Computing Server.
Warning
Port availability is subject to NUS School of Computing firewall policies, which may change without prior notice. Always refer to the official NUS firewall documentation for the latest rules: https://dochub.comp.nus.edu.sg/cf/tech/network/firewall
Open Ports¶
System-Reserved Ports¶
These ports are used by server infrastructure and are not available for user services.
| Port | Protocol | Purpose |
|---|---|---|
| 22 | TCP | SSH access (rate limited) |
| 111 | TCP/UDP | autofs |
| 2049 | TCP/UDP | NFS |
| 2379 | TCP | etcd client (usage reporting) |
| 2380 | TCP | etcd peer (usage reporting) |
| 4000 | TCP | Cgroup Exporter (RAM monitoring) |
| 4001 | TCP | Node Exporter (CPU and general monitoring) |
| 4003 | TCP | NVIDIA GPU Exporter (GPU monitoring) |
User-Available Ports¶
Users may run services on ports within the following ranges:
| Port Range | Protocol | Notes |
|---|---|---|
| 4000-4100 | TCP/UDP | SoC allowed range. Avoid system-reserved ports listed above. |
| 10000-30000 | TCP/UDP | General-purpose range for user services. |
Ports outside these ranges are blocked by default.
Regular users may run sudo ufw status to view the firewall status. (This
command has been allowed for all users.)
User Responsibilities¶
- Only bind ports within the user-available ranges listed above.
- Do not interfere with system-reserved ports or services.
- Terminate services and release ports when no longer needed.
- If you need a port outside the allowed ranges, contact the administrator. Approval depends on NUS firewall policy.