Docker.github.io: "Use a pre-existing network" outdated

[wanno-drijfhout]

File: compose/networking.md, CC @gbarr01

The documentation under "Use a pre-existing network" is outdated ("external.name" is no longer used).

By the way: I'm looking for ways to deploy my stack on (indeed) a pre-existing network, but I just can't get it to work. The following Compose.yaml fragment does cause a separate network to be created ("MyApp_default") instead of using the "intranet" network that already existed.

networks:
  default:
    external: true
    name: intranet

If you could add documentation on what I'm doing wrong, it'd be very much appreciated.

[gbarr01]

@shin- , my understanding is that "external" is _not_ outdated. Can you confirm?

[wanno-drijfhout]

@gbarr01 The exact message is:

WARN[0000] network default: network.external.name is deprecated in favor of network.name

[wanno-drijfhout]

Note: I've also found why I couldn't get it it work. My network (intranet) did exist but it was not 'attachable'. Recreating my network with --attachable solved that particular problem it seems :-).

[gbarr01]

Okay, thanks @Xsysstar , I'll take a look as soon as I can.

[gbarr01]

@shin- , when you get a chance, is using an attachable network the right solution here?

https://docs.docker.com/compose/networking/#use-a-pre-existing-network

[anthraxn8b]

Can confirm this.

Warning message: "[...] network mynet: network.external.name is deprecated in favor of network.name [...]"

In the documentation I only found something about volumes: https://docs.docker.com/compose/compose-file/#external
"[...] external.name was deprecated in version 3.4 file format use name instead [...]"
But this is not about networks...

So how should my brand new (external network) code in version 3.6 look like?

[shin-]

Sorry I missed this.

The recommendation is the same for volumes, networks, secrets and configs ; instead of

foo:
  external:
    name: something

one should now write

foo:
  external: true
  name: something

for versions of the format that support it (that's 3.4+ for volumes and 3.5+ for everything else). These two snippets are functionally equivalent.

[ghost]

Closing this ticket due to its age, and the impending refactor. If you think this is in error, feel free to reopen. Thanks!

[NitroBAY]

Why not updating the doc ? https://docs.docker.com/compose/networking/