WAL archive: FAILED (please make sure WAL shipping is setup)

Question

I am trying to configure Barman to backup. When I do a barman check replica I keep getting:

Server replica:
WAL archive: FAILED (please make sure WAL shipping is setup)
PostgreSQL: OK
superuser: OK
wal_level: OK
directories: OK
retention policy settings: OK
backup maximum age: FAILED (interval provided: 1 day, latest backup age: No available backups)
compression settings: OK
failed backups: OK (there are 0 failed backups)
minimum redundancy requirements: FAILED (have 0 backups, expected at least 2)
ssh: OK (PostgreSQL server)
not in recovery: FAILED (cannot perform exclusive backup on a standby)
archive_mode: OK
archive_command: OK
continuous archiving: OK
archiver errors: OK

I am using Postgresql 9.6 and barman 2.1; I am not sure as to what the issue is could someone help? Here is my Barman server configuration:

description = "Database backup"
conninfo = host=<db-ip> user=postgres dbname=db
backup_method = rsync
ssh_command = ssh postgres@<db-ip>
archiver = on

Answer 1

When running into an error like this, be sure to run barman switch-xlog --force --archive <server_name> as noted in the barman documentation to verify the WAL archiving process.

Answer 2

in brief

Barman's incoming_wals_directory and Postgresql.conf's archive_command not matched as described in details here

details

Another cause is that the not matched between

• Barman's incoming_wals_directory
• Postgresql.conf's archive_command

Bash util to check

barman@backup $ barman show-server pg | grep incoming_wals_directory
# output1
# > incoming_wals_directory: /var/lib/barman/pg/incoming

postgres@pg $ cat /etc/postgresql/10/main/postgresql.conf | grep archive_command
# output2
# > archive_command = 'rsync -a  %p  barman@staging:/var/lib/barman/pg/incoming/%f' 

We must have same path in :output1 and :output2

Make them matched if they don't and don't forget to restart postgres afterward.