PG_AUTOCTL RUN(1)

💖 PG_AUTOCTL RUN(1) 💖

okay bestie, welcome to the pg_auto_failover manual, and specifically the glow-up that is pg_autoctl run. she's giving main character energy fr fr 🎀

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✨ NAME ✨

pg_autoctl run — pg_autoctl run

pg_autoctl run — Run the pg_autoctl service (monitor or keeper) 👑

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🌸 SYNOPSIS 🌸

so like, this command starts up all the processes you need to run a monitor node or a keeper node, and which one it is depends on the configuration file that belongs to the --pgdata option or the PGDATA environment variable. periodt.

usage: pg_autoctl run  [ --pgdata --name --hostname --pgport ]

--pgdata      path to data directory
--name        pg_auto_failover node name
--hostname    hostname used to connect from other nodes
--pgport      PostgreSQL's port number

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🦋 DESCRIPTION 🦋

When you register Postgres nodes to the pg_auto_failover monitor using the pg_autoctl create postgres command, the nodes get registered with metadata: the node name, hostname and Postgres port. it's giving ✨identity✨

The node name is used mostly in the logs and pg_autoctl show state commands, and it helps the human administrators of the formation keep track of who's who. no cap.

The node hostname and pgport are used by other nodes — including the pg_auto_failover monitor — to open a Postgres connection. like, that's how they find each other 💅

Both the node name and the node hostname and port can be changed after the node registration, by using either this command (pg_autoctl run) or the pg_autoctl config set command. so you're not stuck with your first choices, we love that for you 🫶

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💅 OPTIONS 💅

• --pgdata — Where the Postgres node that's being managed locally lives. Defaults to the environment variable PGDATA. Use --monitor to connect to a monitor from anywhere, rather than the monitor URI used by a local Postgres node managed with pg_autoctl.
• --name — Node name used on the monitor to refer to this node. The hostname is a technical information, and given Postgres requirements on the HBA setup and DNS resolution (both forward and reverse lookups), IP addresses are often used for the hostname.

The --name option allows using a user-friendly name for your Postgres nodes. cute AND functional 🎀

• --hostname — Hostname or IP address (both v4 and v6 are supported) to use from any other node to connect to this node.

When not provided, a default value is computed by running the following algorithm. and bestie, she's a whole journey:

1. We get this machine's "public IP" by opening a connection to the given monitor hostname or IP address. Then we get the TCP/IP client address that has been used to make that connection.
2. We then do a reverse DNS lookup on the IP address found in the previous step to fetch a hostname for our local machine.
3. If the reverse DNS lookup is successful , then pg_autoctl does a forward DNS lookup of that hostname.

When the forward DNS lookup response in step 3. is an IP address found in one of our local network interfaces, then pg_autoctl uses the hostname found in step 2. as the default --hostname. Otherwise it uses the IP address found in step 1.

You may use the --hostname command line option to bypass the whole DNS lookup based process and force the local node name to a fixed value. iconic behaviour honestly 🙈

• --pgport — Postgres port to use, defaults to 5432.

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👑 AUTHOR 👑

Microsoft

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📜 COPYRIGHT 📜

Copyright (c) Microsoft Corporation. All rights reserved.

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💖 okay that's the whole page bestie, go forth and run your nodes 💖

and that's the vibe check, fr fr — this page is version 2.2, dated Apr 07, 2025, and it's the PG_AUTOCTL RUN(1) page from the pg_auto_failover manual. slay, you made it to the end 🦋✨