SME Linux 8 Backup terminated: pre-backup failed - status: 256

After workstation restore full system and all function and data normal but 
the workstation backup cannot run and have this message

Backup terminated: pre-backup failed - status: 256

The ldap may be down Please use the command below to fix.

sv d /service/ldap
rm -f /var/lib/ldap/__db.00{1,2,3,4,5,6} /var/lib/ldap/alock
rm -f /var/run/openldap/slapd.{pid,args}
sv u /service/ldap

Good luck!