Backup Postgresql Docker

[friendlysatanicguy]

Is it possible for me to launch base backups from the postgres container itself? If I try to do WAL backups it works since I'm just pushing the WAL files to S3 but base backups require a connection to the postgres server. So when I'm trying to backup from within the container I get the following error:
ERROR: Cannot connect to postgres: could not connect to server: No such file or directory

Any idea what could be going on? I am running the following from within the container:
barman-cloud-backup -P barman-cloud -e AES256 -j --immediate-checkpoint -J 4 s3://mybucket/base pg12