MERLIN LEGEND Communications System Release 7.0
System Programming
555-670-111
Issue 1
April 1999
Programming with SPM
2-28
Using SPM
2
Determining the Release Number of a
Backup File
2
If you have a backup disk but do not know its release number, you may be able to
find this information in the backup header.
Beginning with later versions of Release 1.1, the backup file contains a backup
header 128 bytes long. Approximately 59 of these bytes are currently used. Bytes
55 through 59 of the header contain the MERLIN LEGEND Communication
System Release number, as shown in
. (Release 1.0 and early versions
of Release 1.1 do not contain this information in readable form.)
The release number is found in the first two bytes (four characters) of the
identification number—for example, 0600 = 6.0, 0402 = 4.2.
If the backup file is compressed (Release 1.1 and later), you can read the header
but you cannot read the data area following the header. Use
type
[backup
filename] to read the header on a DOS system or
cat
[backup filename] to read
the header on a UNIX System.
Note that it is the communication system release number, not the version number
of SPM, that reflects whether the backup file is compressed or uncompressed.
Release 1.0 backups are uncompressed and Release 1.1 and later backups are
compressed. Uncompressed files take longer to restore.
Considerations
2
Review the following items before you begin the backup procedure:
■
The communications system does not have to be idle during backup;
however, extension programming is blocked.
■
Any objects that are in a maintenance-busy state are stored in that state.
When you restore system programming, these objects are busied out, even
if they have since been released from the maintenance-busy state.
Table 2-4.
Backup Header: Release Number
Release No.
Build No.
System Size
Mode
Size
2 bytes
12 bytes
1 byte
1 byte
Examples
06 00
32
01
01 (Key)
04 02
02 (Behind Switch)
03 (Hybrid/PBX)
