# port

> port is the PostgreSQL setting that defines the TCP port the server listens on.
---

> [!NOTE]
> **Fact — official short description:** “Sets the TCP port the server listens on.”

## Identity {#identity}

| Field | Value | Meaning |
| --- | --- | --- |
| Type | `integer` | Upstream pg_settings type |
| Context | `postmaster` | Requires a server restart |
| Unit | — | Raw unit |
| Range | `1` – `65535` | Raw limits in the last observed version |
| Enum values | — | — for non-enum types |
| Category | Connections and Authentication / Connection Settings | Upstream classification |
| Latest boot value | `5432` | 5432 |
{.fields meta="-"}

## Lifecycle {#lifecycle}

| Fact | Value |
| --- | --- |
| First observed | PG9.0 (research boundary) |
| Present in | PG9.0–19 Beta 3 |
| Removed in | No |
| Introduction commit | Not asserted: predates the PG9.0 research boundary |
| Commit date | — |
| Discussion | — |

## Default history {#default-history}

| Versions | Raw `boot_val` | Unit | Human value |
| --- | --- | --- | --- |
| PG9.0–19 Beta 3 | `5432` | — | 5432 |
{.full-width caption="Measured PG9.0–19 Beta 3 boot defaults"}

## How it works {#mechanism}

port sets the TCP port the server listens on. One port is used for every TCP listener address and becomes part of client connection strings, service discovery, firewall rules, and health checks.

port is a POSTMASTER-context setting: PostgreSQL reads it during server startup, and a configuration reload or session SET cannot activate a new value.

The listener endpoint combines listen_addresses and port at startup, while pg_hba.conf, TLS, firewalls, routing, and service discovery determine which clients can use it.

## Tuning advice {#tuning-advice}

> [!TIP]
> **Advice.** These are workload-specific starting points and must be validated with measurements.

| Workload | Guidance |
| --- | --- |
| OLTP | Set port from the service topology and expose only required interfaces or ports. Validate poolers, health checks, pg_hba.conf, firewalls, failover, and restart sequencing together. |
| OLAP | Use an explicit analytical endpoint or network when isolation is required, but keep connection information consistent across failover targets. |
| Small nodes | Prefer local-only exposure unless remote access is required. Preserve a tested administrative route before changing port and restarting. |
{.full-width}

## Pigsty {#pigsty}

Values use the fixed 8-vCPU, 32-GiB, 100-GiB SSD fixture and render the current Pigsty templates for PG19 Beta 3; this does not assert current Pigsty support for that historical or beta release.

| Template | Effective value | Versus upstream boot | Source expression |
| --- | --- | --- | --- |
| OLTP | Unmodified | — | — |
| OLAP | Unmodified | — | — |
| CRIT | Unmodified | — | — |
| TINY | Unmodified | — | — |
{.full-width}

> [!CAUTION]
> **Advice — pending human review.** Fact from the current Pigsty template projection: OLTP: PG9.0–19 Beta 3 unmodified; OLAP: PG9.0–19 Beta 3 unmodified; CRIT: PG9.0–19 Beta 3 unmodified; TINY: PG9.0–19 Beta 3 unmodified. No Pigsty-specific rationale is inferred from an absent override.

## Common pitfalls {#common-pitfalls}

- Expecting a reload or SET to activate port, although it requires a controlled server restart.
- Assuming a bound address or port grants access; pg_hba.conf and operating-system or network controls still apply.
- Changing a startup-only endpoint without updating discovery, health checks, firewalls, clients, and the administrative recovery path.
- Changing port globally without a rollback plan and a client or operational compatibility test.

## Related parameters {#related-parameters}

[`listen_addresses`](/parameters/listen-addresses/) · [`max_connections`](/parameters/max-connections/) · [`reserved_connections`](/parameters/reserved-connections/) · [`superuser_reserved_connections`](/parameters/superuser-reserved-connections/) · [`unix_socket_directories`](/parameters/unix-socket-directories/)

## References {#references}

- [PostgreSQL 19 Beta 3 — port](https://www.postgresql.org/docs/19/runtime-config-connection.html#GUC-PORT)
- [PostgreSQL 19 release notes](https://www.postgresql.org/docs/19/release-19.html)
- [Machine-readable GUC export](/data/guc.jsonl)