pajama

iiug.org에서 onbar에서 사용되는 XBSA API에 대한 설명을 발췌하였습니다. 

onbar 명령으로 백업을 수행하면 onbar 프로세스는 백업 솔루션의 프로세스와 통신하게 되는데, 그 과정에서 아래의 API들을 사용하게 됩니다.

onbar로 백업을 하고 계신 곳에서는 백업 로그에서 아래의 일부 API 이름을 보셨을 겁니다.

Onbar can communicate with multiple storage managers. The reason we can pull this off is because recently a standard api has been developed so that different vendors can communicate with each other. This standard/language is know as XBSA. Below are the XBSA calls that onbar uses in order to backup and restore dbspaces to/from the online engine. The functions below are the complete set of XBSA call. It is mearly the calls that onbar uses.

• BSABeginTxn()- starts an XBSA API transaction.
• BSACreateObject()- Creates an XBSA object. This basically tells that storage manager to make room for a new backup. The storage manager passes back the copyid (inside the objectdescriptor) that is the unique identifier that onbar uses when it need to get that back/object.
• BSAEndData()-Tells the storage manager that there is no more data to send. (we are finished sending data associated with that particular object)
• BSAEndTxn()- Tell the storage manager that we are finished with a backup transaction.
• BSAGetData()- This function returns a single buffer of data from that storage manager. We pass it the copyid (in the object descriptor) and the storage manager is responsible for finding the requested data.
• BSAGetObject()- Called to gather information about a particular storage manager object (ie, date created , size, owner etc).
• BSAInit()- connects to the storage manager and starts a session. This function will return a 'handle' that is a unique identifier associated to that session.
• BSAQueryApiVersion()- Called to validate which version of the XBSA libraries onbar is talking to.
• BSASendData()- Sends a buffer full of data to the storage manager.
• BSATerminate()- Terminates a session with the storage manager. It also frees up and resources that were allocated in the BSAinit call.

Below is a simplistic diagram on how an XBSA application goes. onbar (which is an XBSA applicalion in it self) follows this flow chart as well when creating/restoring archives. onbar will loop calling BSASendData (and BSAGetDATA) until the is no more data to process.

출처 : http://www.iiug.org/onbar/xbsa.html