Choosing a device number for disk init

Adaptive Server automatically specifies the next available identifying number for the database device. This is the virtual device number (vdevno). You do not have to specify this number when you issue the disk init command.

If you choose to manually select the vdevno, it must be unique among the devices used by Adaptive Server. Device number 0 represents the master device. The highest number must be one less than the number of database devices for which your system is configured. For example, for a system with a default configuration of 10 devices, the legal device numbers are 1–9. To see the configuration value for your system, execute sp_configure "number of devices" and check the run value:

sp_configure "number of devices"
Parameter name  Default  Memory Used  Config Value  Run Value
--------------- -------  -----------  ------------  ----------
number of devices    10            0            10         10

To see the numbers already in use for vdevno, look in the device_number column of the report from sp_helpdevice, or use the following query to list all the device numbers currently in use:

select distinct low/16777216 
    from sysdevices 
    order by low 

Adaptive Server is originally configured for 10 devices. You may be limited to a smaller number of devices by operating system constraints. See the discussion of sp_configure, which is used to change configuration parameters, in Chapter 5, “Setting Configuration Parameters.”