Help admins using debs from nuking their config when upgrading

[DMRobertson]

It sounds like people often edit homeserver.yaml in place. When they update to a newer release, this can get nuked if they're not sure how to interpret dpkg's "you've changed a file that's been update" message. See e.g.

• Login not possible since upgrade from 1.50.2 to 1.51.0 #11826
• apt update/upgrade Configuration file '/etc/matrix-synapse/homeserver.yaml' ==> Modified (by you or by a script) since installation. #11238

  unfortunately when you search google: "matrix-synapse-py3" "registration_shared_secret"
  LITERALLY all the guides have you editing the main homeserver.yaml file.

• APT package matrix-synapse-py3 clobbers config in homeserver.yaml #7222

Suggestion:

• rename homeserver.yaml to homeserver.example.yaml
• make synapse refuse to start if its config file is called homeserver.yaml.example
• change docs to say that you need to copy and rename homeserver.example,yaml

[richvdh]

I think this is basically the same as #8159 ?

[DMRobertson]

Agreed.