Problems When Accessing Disc Changers - HP J3278B - SureStore CD-ROM Server/Tower 7 NAS Server User Manual

Note
A-8 Troubleshooting

Problems When Accessing Disc Changers

Disc changers, with up to 8 discs each, are supported. Up to
56 CD-ROM discs are supported through LUN (Logical Unit
Number) addressing.
The CD-ROM server has a parameter,
sets how long a user has exclusive access to a CD-ROM during a
data-read operation. This is to prevent disc-changer flutter in
order to optimize access speed when many users are accessing
different discs in the same changer.
Disc-changer flutter can occur if a user requests access to a
CD-ROM when another user is already reading data from a
different CD-ROM. The changer may then attempt to service
both requests by repeatedly changing between the two
CD-ROMs and transferring a small amount of data each time.
Because of the relatively long time needed to change CD-ROMs,
the data transfer rate to both users will become unacceptably
low.
The
JukeBoxLockTime
are simultaneous requests for access to different CD-ROMs, a
sizable block of data is transferred to each user before the
CD-ROM access is changed.
• If the
JukeBoxLockTime
transfer rate will be unacceptably low.
• If the
JukeBoxLockTime
will time-out on a second user's request before the first
user's access is completed. This will result in users receiving
a 'CD-ROM not available' notice.
The default setting is 0 seconds which disables this function; you
can adjust this value by following the instructions given in
chapter 5.
JukeBoxLockTime
parameter will ensure that when there
parameter is set too low the data
is set too high the CD-ROM drive
, which