Server switching method and server system equipped therewith

A server switching method for a server system that includes active servers, at least one standby server and a management server that are equipped with storage devices and process modules respectively and that are all connected through a network, the method comprising:

• the management server:
• delivering a disk image of an appropriate active server to the standby server in advance;
• holding service provision management server information in a storage device of its own;
• when receiving the report that the active server has failed, judging whether or not it is possible for the standby server to perform the service of the failed active server based on the service provision management server information held in the storage device;
• and
• instructing the standby server to perform the service of the active server, if possible, wherein:
• if the management server judges the standby server to be incapable of performing the service of the failed active server, the management server sends, to the standby server, a disk image with the use of which the standby server can perform the service of the active server, and
• the management server:
• holds hardware management information in the storage device of its own;
• judges whether the type of the process module of the active server and that of the standby server coincide or not based on the hardware management information when the management server sends the disk image to the standby server;
• and
• if they do not coincide, delivers a disk image that is fit to the type of the process module of the standby server.

A server system comprising:

• an active server;
• at least one standby server;
• and
• a management server that are connected through a network to the active server and the standby server, wherein:
• the active server, the standby server, and the management server are equipped with process modules and storage devices respectively,
• the process module of the management server stores the disk image of the active server in advance in the storage device of the standby server and holds service provision management server information in the storage device of the management server,
• when the management server receives the report that the active server has failed, the process module of the management server judges whether or not it is possible for the standby server to perform the service of the failed active server based on the service provision management server information,
• the process module instructs the standby server to perform the service of the active server, if possible,
• the process module of the management server judges whether or not it is possible for the standby server to perform the service of the failed active server based on disk image names that are included in the service provision management server information,
• the management server holds software management information possessed by the disk image in the storage device of its own,
• the process module of the management server judges whether the disk image stored in advance in the storage device of the standby server lacks some pieces of software or not based on both the service provision management server information and the software management information and if the disk image stored in advance in the storage device lacks any pieces of software, and
• the process module:
• compares the time needed to install the lacking pieces of software with the time to deliver another disk image;
• installs the lacking pieces of software on the standby server and changes the setting values of the software if the time needed to install the lacking pieces of software on the standby server is shorter;
• and
• delivers the disk image to the standby server if the time to deliver the disk image to the standby server is shorter.