Using separate log file for stderr during backup

infrastructure/server-setup/tasks/backups/crontab.yml

@@ -20,7 +20,7 @@
     name: 'backup opencrvs'
     minute: '0'
     hour: '0'
-    job: 'bash {{ crontab_user_home }}/backup.sh --passphrase={{ backup_encryption_passphrase }} --ssh_user={{ backup_server_user }} --ssh_host={{ backup_hostname }} --ssh_port={{ backup_port }} --remote_dir={{ backup_server_remote_target_directory }} --replicas=1 >> /var/log/opencrvs-backup.log 2>&1'
+    job: 'bash {{ crontab_user_home }}/backup.sh --passphrase={{ backup_encryption_passphrase }} --ssh_user={{ backup_server_user }} --ssh_host={{ backup_hostname }} --ssh_port={{ backup_port }} --remote_dir={{ backup_server_remote_target_directory }} --replicas=1 >> /var/log/opencrvs-backup.log 2> /var/log/opencrvs-backup.error.log'
     state: "{{ 'present' if (backup_hostname is defined and backup_encryption_passphrase and (enable_backups | default(false))) else 'absent' }}"
 
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