 | ||
| Interaction of multiple require and use constraints | ||
|---|---|---|
| Prev | Specifying allocation constraints for vxassist operations with the use clause and the require clause | Next |
| ||
| Interaction of multiple require and use constraints | ||
|---|---|---|
| Prev | Specifying allocation constraints for vxassist operations with the use clause and the require clause | Next |
You can specify multiple use or require clauses on the vxassist command line. Not all combinations are supported. However, all possible constraint specifications can be achieved with the supported combinations.
The scope for a constraint can be data-specific (datause or datarequire), log-specific (loguse or logrequire) or general, which applies to both data and log (use or require).
Note: |
Symantec recommends that you do not combine use or require constraints with direct storage-specifications or other clauses like alloc or logdisk. |
The following rules apply when multiple use or require clauses are specified:
Multiple use constraints of the same scope are unionized, so that at least one of the storage specifications is satisfied. That is, multiple use clauses; multiple datause clauses; or multiple loguse clauses.
Multiple require constraints of the same scope are intersected, so that all the storage specifications are satisfied. That is, multiple require clauses; multiple datarequire clauses; or multiple logrequire clauses.
Require and use constraints of the same scope are mutually intersected. That is, require clauses and use clauses; datarequire clauses and datause clauses; or logrequire clauses and loguse clauses. At least one of the use storage specifications must be satisfied and all of the require storage specifications are satisfied. For example, if a datause clause and a datarequire clause are used together, the allocation for the data must meet at least one of the datause specifications and all of the datarequire specifications.
Data-specific constraints and log-specific constraints can be used together. They are applied independently to data and logs respectively. That is, datause clause with loguse clause or logrequire clause; datarequire clause with loguse clause or logrequire clause . For example, a datarequire clause can be used to control data allocation along with a logrequire clause to control log allocation.
The vxassist command does not support a mix of general scope constraints with data-specific or log-specific constraints. For example, a require clause cannot be used along with the logrequire clause or a datarequire clause. However, all possible constraint specifications can be achieved with the supported combinations.
Table: Combinations of require and use constraints summarizes these rules for the interaction of each type of constraint if multiple constraints are specified.
Table: Combinations of require and use constraints