Upgrade to buster and remove filebeat

target/filebeat.yml.tmpl

@@ -1,13 +0,0 @@
-output:
-  logstash:
-    enabled: true
-    hosts:
-      - $ELK_HOST:$ELK_PORT
-
-filebeat:
-  prospectors:
-    -
-      paths:
-        - /var/log/mail/mail.log
-      document_type: syslog
-

target/supervisor/conf.d/supervisor-app.conf

@@ -65,14 +65,6 @@ stdout_logfile=/var/log/supervisor/%(program_name)s.log
 stderr_logfile=/var/log/supervisor/%(program_name)s.log
 command=/usr/sbin/dovecot -F -c /etc/dovecot/dovecot.conf
 
-[program:filebeat]
-startsecs=0
-autostart=false
-autorestart=true
-stdout_logfile=/var/log/supervisor/%(program_name)s.log
-stderr_logfile=/var/log/supervisor/%(program_name)s.log
-command=/usr/bin/filebeat -c /etc/filebeat/filebeat.yml
-
 [program:clamav]
 startsecs=0
 autostart=false