Fix error in determine database type on script 'get_mail_domains.sh'.

get_mail_domains.sh

@@ -97,6 +97,8 @@ else
    fi
 fi
 
+[[ -n "$db_type" ]] || db_type="$DEFAULT_db_type"
+
 if [[ "$db_type" != "pgsql" ]] && [[ "$db_type" != "mysql" ]]; then
    fatal "Unknown Database Type '$db_type' for Password Database (Parameter db_type)"
 fi
@@ -132,7 +134,7 @@ fi
 
 echo ""
 echononl "   Collect supported domains at this server.."
-if $mysql ; then
+if [[ "$cwdb_type" = "mysql" ]] ; then
    domains=$(mysql $mysql_credential_args "$db_name"  -N -s -e \
       "SELECT domain FROM domain ORDER by domain" 2> "$log_messages")
 else