ASSIGNING AN ALTERNATE TRACK (1) analyzes a track and, if necessary, assigns an alternate
or (2) bypasses testing, and assigns an alternate. You .ust specify the
tracks for which you wish alternates with a GETALT statement. an Alternate l!ack In alternate track (if
available) -Is-assigned for a track specified for testing and found
defective. If the defective track has had an alternate previously
assigned, a new alternate track is assigned. If the defective track is
an unassigned alternate track, it is flagged to prevent its future use
and another alternate track is selected. The alternate track address is made known to the operator.
If a track is tested and found to be "not defective," no alternate is
assigned. The operator is notified by a aessage. The program's defective
track checking feature can be bypassed, and an alternate track can be
assigned for any track, whether it is permanently defective or not. If
the specified track is an alternate, a new alternate track is assigned.
If the specified track is an unassigned alternate, it is flagged to
prevent its future use. For 3330, 3340, and 3350 minidisks you aust on the real disk. Any references thereafter to ainidisk are referred to the alternate track.
assign the alternate
that track on the Section 4. V8/370 Service Prograas 189

Any number of alternate tracks can be assigned in a single job by including one GETALT statement for each track. The GETALT statement can
follow the MSG statement. The format of the GETALT statement is: [name] TODEV=xxxx TOADDR=cuu IGETALT I I I I I I I ITODEV=xxxx I,TOADDB=cuu I,TBICK=cccchhhh I,VOLID=serial I[,FLAGTEST=NO] 1[,PASSES=n] I[,BYPASS=YES] 1[,MODEL=n] is the device type of the direct access device.
is the direct channel number (c) and unit number (uu) of the
direct access device.
TRACK=cccchhhh
is the address of the track for which an alternate is
requested, where cccc is the cylinder number and hhhh is the
head number. These are hexadecimal numbers. YOLID=serial is the volume serial number of the disk or minidisk to which
an alternate track is to be assigned. If serial matches the volume serial number found on this disk or minidisk, the
alternate track assignment proceeds. If it does not match, the operator is notified. FLAGTEST=NO (used when testing before assigning an alternate) specifies
that the program not check for a previously flagged track
before a surface analysis is attempted on this track (disk
storage devices only). PASSES=n (used when testing before assigning an alternate) specifies
that the program's defective track checking feature is to make n number of passes (from 1 to 225j when performing a surface
analysis. If PASSES is omitted, one pass is lade on this
track. 190 VM/370 Operator's Guide