BackPak H4.00 Catalog Sync Option

Disaster/Recovery Option Description
10 BackPak H4.00 Catalog Sync Option
data store), and non-BackPak volumes, it is suggested to create a distinct DSM/TC
catalog to receive the entries created by BackPak Catalog Sync import for each
primary source.
The main reason for this isolation is that FILEID naming convention generally does
not ensure the uniqueness of a FILEID across an enterprise; the collision between
FILEID created by DSM/TC for local backups and FILEID created by BackPak will
corrupt the DSM/TC catalogue.
A second reason is the greater granularity of distinct catalogues allows to manage
these catalogues by other means, such as BACKUP/RESTORE and by more relaxed
use of pattern in MEDIACOM commands.
Because a PRIMARY system can become SECONDARY, it is also recommended to
isolate the source of the DSM/TC replication in a separate catalogue.
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Between a primary and a secondary site, the DSM/TC VOLCAT, FILECAT names are
typically different – at least by their node name. There are cases of ‘mirror’ nodes
where the nodes name is identical, see more for this in Configure the secondary Data
store.
The POOL names can identical or different without meaningful impact.
Uniqueness of volume labels
An important consideration is a tape volume name (tape label) must be unique in a
DSM/TC system search space. That system search space can encompass the two
NonStop systems on Expand, primary and secondary systems.
In this case, it will be impossible to insert the volume in the secondary environment
because the same name exists in the remote primary environment.
As bypass to this problem, it could be possible to create a DSM/TC secondary pool to
exclude it from the system search space. But there are two inconvenients:
- to manage properly volumes with same name, DSM/TC requires that volumes
in such pools be used with specification of a tape drive in the TAPECATALOG
DEFINE.
- BackPak requiring label uniqueness, will need two or more BackPak domains
to operate all volumes
The specification of a specific tape drive in TAPE DEFINEs prevents the automatic
drive selection by BackPak, requires more manual care for avoiding conflicts between
concurrent jobs and for avoiding drives that might be temporary not operational.
When both primary and secondary systems are on Expand, the scope of DSM/TC
system search space is normally reduced, making the primary and secondary
systems not in the same system search space:
- With the replication, the need for remote DSM/TC operations is reduced