Unable to receive WAL files with barman

I've been scratching my head to solve the following error, but haven't made much progress:

$ barman switch-wal --force --archive --archive-timeout 180 pg

The WAL file 0000000100000059000000FF has been closed on server 'pg'
Waiting for the WAL file 0000000100000059000000FF from server 'pg' (max: 180 seconds)
ERROR: The WAL file 0000000100000059000000FF has not been received in 180 seconds

I had earlier configured barman on a throwaway VPS and everything worked fine. But when I tried replicating this on our final EC2 instance, I ran into the issue mentioned above. I have ensured the following (even though I don't remember doing this on the VPS):

• SSH from barman => pg is working

• SSH from pg => barman is working

• All firewall rules on 'pg' have been disabled, temporarily

What could be the issue here?

Edit: Adding the output of barman check pg

```
Server pg:
2017-12-08 05:56:31,841 [14559] barman.server ERROR: Check 'WAL archive' failed for server 'pg'
WAL archive: FAILED (please make sure WAL shipping is setup)
PostgreSQL: OK
is_superuser: OK
PostgreSQL streaming: OK
wal_level: OK
2017-12-08 05:56:34,174 [14559] barman.server ERROR: Check 'replication slot' failed for server 'pg'
replication slot: FAILED (slot 'pgbackup' not active: is 'receive-wal' running?)
directories: OK
retention policy settings: OK
2017-12-08 05:56:34,175 [14559] barman.server ERROR: Check 'backup maximum age' failed for server 'pg'
backup maximum age: FAILED (interval provided: 14 days, latest backup age: No available backups)
compression settings: OK
failed backups: OK (there are 0 failed backups)
2017-12-08 05:56:34,175 [14559] barman.server ERROR: Check 'minimum redundancy requirements' failed for server 'pg'
minimum redundancy requirements: FAILED (have 0 backups, expected at least 3)
pg_basebackup: OK
pg_basebackup compatible: OK
pg_basebackup supports tablespaces mapping: OK
pg_receivexlog: OK
pg_rec

When you run into a problem like this one, be sure to double-check your logs, the barman check command, and make sure you set a barman cron entry to start barman receive-wal. That needs to be running before you can execute barman switch-wal and finish your setup. =)

StackExchange Database Administrators Q#192162, answer score: 5