Appendix B Environment File Variables for Metrocluster SRDF

Default: 0

This variable indicates that when the package is being started on an R1 host, the Symmetrix is in a Read/Write state, and the SRDF links are down, the package will be automatically started. Although the script cannot check the state of the Symmetrix on the R2 side to validate conditions, the Symmetrix on the R1 side is in a ‘normal’ state. To require operator intervention before starting the package under these conditions, set AUTOR1RWNL=1 and create the file /etc/cmcluster/package_name/FORCEFLAG.

Default: 1

This variable indicates that when the package is being started on an R1 host and the Symmetrix is being synchronized from the Symmetrix on the R2 side, the package will halt unless the operator creates the $PKGDIR/FORCEFLAG file.The package halts because performance degradation of the application will occur while the resynchronization is in progress. More importantly, it is better to wait for the resynchronization to finish to guarantee that the data are consistent even in the case of a rolling disaster where a second failure occurs before the first failure is recovered from.To always automatically start the package even when resynchronization is in progress, set AUTOR1UIP=0. Doing so will result in inconsistent data in case of a rolling disaster.

Default: 1

AUTOR2WDNL=1 indicates that when the package is being started on an R2 host, the Symmetrix is in a Write-disabled state, and the SRDF links are down, the package will not be started. Since we cannot check the state of the Symmetrix on the R1 side to validate conditions, the data on the R2 side may be non-current and thus a risk that data loss will occur when starting the package up on the R2 side. To have automatic package startup under these conditions, set AUTOR2WDNL=0

Default: 1

AUTOR2RWNL=1 indicates that when the package is being started on an R2 host, the Symmetrix is in a read/write state, and the SRDF links are down, the package will not be started. Since we cannot check the state of the Symmetrix on the R1 side to validate conditions, the data on the R2 side may be non-current and thus a risk that data loss will occur when starting the package up on the R2 side. To have automatic package startup under these conditions, set AUTOR2RWNL=0

Default: 0

A value of 0 for this variable indicates that when the package is being started on an R2 host and at least one (but not all) SRDF links are down, the package will be automatically started. This will normally be the case when the ‘Partitioned+Suspended’ RDF Pairstate exists. We cannot check the state of all Symmetrix voumes on the R1 side to validate conditions, but the Symmetrix on the R2 side should be in a ‘normal’ state. To require operator intervention before starting the package under these conditions, set AUTOR2XXNL=1.

Default: 0

A value of 0 for this variable indicates that when the package is failing over to DATA Center 2, the package will not perform a R1/R2 swap. To have the package perform a R1/R2 swap, set AUTOSWAPR2=1 and an automatic R1/R2 swap will occur only when the SRDF link and the two Symmetrix are properly functioning.

If AUTOSWAPR2 is set to 1, then CONSISTENCYGROUPS can not be set to 1.

Ensure that you have the minumum requirements for R1/R2 Swapping by referring to most recent version of the Metroclusters release notes.

This parameter defines the clustering environment in which the script is used. Should be set to “metro” if this is a Metrocluster environment and “continental” if this is a Continentalclusters environment. A type of “continental” is supported only when the HP Continentalclusters product is installed.

Default: 0

This parameter tells Metrocluster whether or not consistency groups were used in configuring the R1 and R2 volumes on the Symmetrix frames. A value of 0 is the normal setting if you are not using consistency groups. A value of 1 indicates that you are using consistency groups. (Consistency groups are required for M by N configurations.)

If CONSISTENCYGROUPS is set to 1, AUTOSWAPR2 cannot be set to 1. Ensure that you have the minumum requirements for Consistency Groups by referring to Metroclusters release notes.

This variable contains the name of the Symmetrix device group for the package on that node, which contains the name of the consistency group in an M by N configuration.

Has been modified to include the path name of the Symmetrix SymCLI commands. This should be set to the default location of /usr/symcli/bin unless you have changed the location.

In addition to indicating the location of the package control scripts, this variable also will be used for the following files:

Default: 5.

This is the number of times a SymCLI command is repeated before returning an error. Use the default value for the first package, and slightly larger numbers for additional packages making sure that the total of RETRY*RETRYTIME is approximately 5 minutes.

Larger values for RETRY may cause the start-up time for the package to increase when there are multiple packages starting concurrently in the cluster that access the Symmetrix arrays.

Default: 5.

This is the is the number of seconds between retries. The default value of 5 seconds should be used for the first package. The values should be slightly different for other packages. RETRYTIME should increase by two seconds for each package. The product of RETRY * RETRYTIME should be approximately five minutes. These variables are used to decide how often and how many times to retry the Symmetrix status and state change commands.Larger values for RETRYTIME may cause the start-up time for the package to increase when there are multiple packages starting concurrently in the cluster that access the Symmetrix arrays.