Rudder

When I upgrade a SLES12 on in 5.0.17 to 6.1-nightly the upgrade script failed with (see upgrade.log)
I try to run service rudder-jetty restart but the webapp is still blocked on the loading page.

server:~ # systemctl status rudder-jetty.service
rudder-jetty.service - Jetty Web Application Server
   Loaded: loaded (/usr/lib/systemd/system/rudder-jetty.service; enabled)
   Active: failed (Result: exit-code) since Tue 2021-03-16 15:37:26 CET; 2min 52s ago
  Process: 4685 ExecStart=/opt/rudder/bin/rudder-jetty.sh start (code=exited, status=1/FAILURE)

Mar 16 15:36:25 server rudder-jetty.sh[4685]: Setting umask to 0007
Mar 16 15:37:26 server rudder-jetty.sh[4685]: Starting Jetty: . . . . . . . . . . . . . . . FAILED Tue Mar 16 15:37:26 CET 2021
Mar 16 15:37:26 server systemd[1]: Failed to start Jetty Web Application Server.

server:~ # journalctl -xn
-- Logs begin at Tue 2021-03-16 10:53:57 CET, end at Tue 2021-03-16 15:40:01 CET. --
Mar 16 15:38:58 server cf-serverd[15075]: CFEngine(server) rudder Remote host '192.168.7.3' not in allowconnects, denying connection
Mar 16 15:38:58 server cf-serverd[15075]: error: Remote host '192.168.7.3' not in allowconnects, denying connection
Mar 16 15:38:58 server cf-serverd[15075]: CFEngine(server) rudder Remote host '192.168.7.3' not in allowconnects, denying connection
Mar 16 15:38:58 server cf-serverd[15075]: error: Remote host '192.168.7.3' not in allowconnects, denying connection
Mar 16 15:40:01 server cron[4907]: pam_unix(crond:session): session opened for user root by (uid=0)
Mar 16 15:40:01 server cron[4906]: pam_unix(crond:session): session opened for user root by (uid=0)
Mar 16 15:40:01 server systemd[4908]: pam_unix(systemd-user:session): session opened for user root by (uid=0)
Mar 16 15:40:01 server CRON[4910]: (root) CMD (/opt/rudder/bin/relay-cleanup >/dev/null)
Mar 16 15:40:01 server CRON[4911]: (root) CMD (/opt/rudder/bin/rudder agent check -q >> /var/log/rudder/agent-check/check.log 2>&1)
Mar 16 15:40:01 server CRON[4907]: pam_unix(crond:session): session closed for user root

There is some errors in the webapp (see the complete log in webapp_err.log) :

[2021-03-16 11:02:02] ERROR com.normation.rudder.services.policies.ParallelSequence - Failure in boxToEither: Error when calculating configuration for node 'relay.rudder.local' (9ddab0eb-ba7f-499b-a43d-4c99692aec87) <- Error for node '9ddab0eb-ba7f-499b-a43d-4c99692aec87' bundle creation <- We could not generate policies for server '9ddab0eb-ba7f-499b-a43d-4c99692aec87', therefore making updates for nodes behind it unavailable. Maybe you are missing 'scale out' plugin?
[2021-03-16 11:02:02] INFO  policy.generation - Policy generation completed in:           
[2021-03-16 11:02:02] ERROR policy.generation - Error when updating policy, reason was: Cannot write nodes configuration <- Error when calculating configuration for node 'relay.rudder.local' (9ddab0eb-ba7f-499b-a43d-4c99692aec87) <- Error for node '9ddab0eb-ba7f-499b-a43d-4c99692aec87' bundle creation <- We could not generate policies for server '9ddab0eb-ba7f-499b-a43d-4c99692aec87', therefore making updates for nodes behind it unavailable. Maybe you are missing 'scale out' plugin?
[2021-03-16 11:02:02] INFO  policy.generation - Flag file '/opt/rudder/etc/policy-update-running' successfully removed
[2021-03-16 11:02:02] ERROR policy.generation - Policy update error for process '6' at 2021-03-16 11:02:02: Cannot write nodes configuration
[2021-03-16 11:05:57] ERROR com.normation.rudder.rest.RestUtils - "The node with id 88af1763-d20b-4f03-b1de-b12bfed7c75a was not found in removed nodes"