Configuring HP-UX For Peripherals

172 Chapter6

Conﬁguring Magneto-Optical Devices

Planning to Conﬁgure a Magneto-Optical Device

Planning to Conﬁgure a Magneto-Optical

Device

Magneto-optical disk devices are conﬁgured into the operating system

much like a SCSI hard disk drive. Choose the device drivers that must be

present in the kernel for HP-UX to communicate with your

magneto-optical device based on:

• whether you are conﬁguring a single disk or a magneto-optical disk

library

• the architecture and interface to which you are conﬁguring the

device.

Characteristics of Magneto-Optical Devices

Magneto-optical devices yield good performance if data is distributed

properly within its structural framework.

The size of an individual magneto-optical disk device makes it suitable

for use as a boot disk, though its performance does not match that of a

standard hard disk. Series 800 systems cannot be booted from

magneto-optical devices.

Magneto-optical disk libraries contain multiple optical disks and

multiple optical drives. HP offers several magneto-optical disk library

products, with various capacity ranges and hardware conﬁgurations.

Each magneto-optical disk has two surfaces (sides), each of which

appears to HP-UX as if it were an entire disk that can be used for a

mountable ﬁle system or for raw access. Optical disk surfaces may be

kept on- or off-line, as use requires. You may access simultaneously only

as many auto changer surfaces are there are autochthons drives. (This is

a change in implementation.) SAM will also allow access to only as many

surfaces as there are drives.

NOTE If you exceed the number of drives, the request for the additional surface

will either wait (sleep) without time outs, or it will fail with an EBUSY

error (indicating the device is currently busy). The resultant behavior

depends on the speciﬁc operation. Requests to execute mount,

mediainit, or newfs on surfaces will fail with an EBUSY error when all