Recently, Open Source Software (OSS) has become used at many places. However, the use of an OSS is hard for its novice users, because many OSSes have few good manuals. To solve this problem, we have proposed a method of automatically generating a web manual for installing an OSS by editing the log information recorded during the installation process by a skilled user. However, many OSS require to make changes the configuration file. In addition to that more systems are adopting OSS as middlewares such as application servers and DBMSs (Database Management Systems). For these OSS middlewares, it is known that even the processing performance is low under their default settings a great improvement is seen by optimizing their system setting. Therefore, in this research, aming at accumulation of system optimizing technology, an automatic generation of web-based configuration manual is proposed.