Error message with pg_dump and PostgreSQL 14 - postgresql

Question

We use PostgreSQL for our database of Speedy Net. I had a production server with PostgreSQL 13, and I backed up my database with the following command:
pg_dump -U postgres -h localhost "speedy_net" | gzip > <file_name>.sql.gz
It worked with PostgreSQL 13, but recently I upgraded my server to Ubuntu 22.04.1 LTS and PostgreSQL 14. I loaded the database from SQL and everything works properly, but now I can't backup the database - I get the following error message:
pg_dump: error: connection to server at "localhost" (::1), port 5432 failed: fe_sendauth: no password supplied
Now, something has changed in the configuration file from PostgreSQL 13 to 14. In PostgreSQL 13, the file /etc/postgresql/13/main/pg_hba.conf was:
# Database administrative login by Unix domain socket
local all postgres peer
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all peer
# IPv4 local connections:
host all all 127.0.0.1/32 trust
# IPv6 local connections:
host all all ::1/128 md5
# Allow replication connections from localhost, by a user with the
# replication privilege.
local replication all peer
host replication all 127.0.0.1/32 md5
host replication all ::1/128 md5
And in PostgreSQL 14 the file /etc/postgresql/14/main/pg_hba.conf is:
# Database administrative login by Unix domain socket
local all postgres peer
local all speedy_net trust
# TYPE DATABASE USER ADDRESS METHOD
# "local" is for Unix domain socket connections only
local all all peer
# IPv4 local connections:
host all all 127.0.0.1/32 trust
# IPv6 local connections:
host all all ::1/128 scram-sha-256
# Allow replication connections from localhost, by a user with the
# replication privilege.
local replication all peer
host replication all 127.0.0.1/32 scram-sha-256
host replication all ::1/128 scram-sha-256
Notice, the line local all speedy_net trust is new. Is this line causing problems? I had to add it because otherwise I couldn't load the database from SQL.
Do you know how I fix it so that backups will work? If I run the command pg_dump -U postgres -h localhost "speedy_net" manually I get prompted for password, but there is no password and it worked with PostgreSQL 13.
Maybe I need to change the password? How do I do it?

Answer 1

The line that is causing the problems in the new file is
host all all ::1/128 scram-sha-256
That requires you to supply a password. You have two choices:
Use a different authentication method. trust would allow you to login without a password (since you are using it with “localhost” in IPv4, why not with IPv6?). If you don't want that, certificate authentication would be an option.
Create a password file on the new machine. Since you forced password authentication on the old machine, that's probably what you used there.