The effect of -b changes, depending on whether -w is present.
-b without -w creates a new master device as named by -d (the default is d_master) and with the page size as specified by -z (the default is 2048):
If the named device already exists as an OS file, the attempt fails, and you must remove the existing file and try again.
If the named device names an existing raw partition, the attempt fails unless you include the -f flag. This reinitializes the raw partition as a server master device.
-b with -w master tells dataserver to use the size specified in -z for the master device when recreating the master database. It implies nothing about creating a new device.
-w may or may not require additional flags. If you use:
-w model – the -z and -b flags are accepted but ignored.
-w master for new installations – the -z and -b parameters are not required because the device size information is stored in the config_block.
-wmaster to upgrade older installations:
The server requires -b and/or -z if the config_block does not contain a valid entry for the associated sizes. The command fails if it can't get valid data for the page size or device size.
You may provide -b and/or -z when the config_block contains valid entries for the sizes they represent. However if the sizes do not match what is in the config_block, add -f to force your new size preferences.
-f may appear without either -b or -z, because -f also instructs the server to accept damaged allocation pages as belonging to the master database. This is useful for restoring badly corrupted databases. If you specify -w master -f, the server assigns to the master database every allocation page on the named master device that does not belong to some other database than master.