C Environment File Variables for Metrocluster with EMC SRDF

This appendix lists all Serviceguard control script variables that have been modified or added for Metrocluster with EMC SRDF. It is recommended that you use the default settings for most of these variables, so exercise caution when modifying them:

AUTOR1RWSUSP

Default: 0

 

This variable is used to indicate whether a package should be

 

automatically started when it fails over from an R1 host to another R1

 

host and the device group is in suspended state. If it sets to 0, the

 

package will halt unless ${PKGDIR}/FORCEFLAG file has been

 

created. The package halts because it is not known what has caused

 

this condition. This could be caused by an operational error or a

 

Symmetrix internal event, such as primary memory full. If in this situation

 

you want to automatically start the package, AUTOR1RWSUSP should

 

be set to 1.

AUTOR1RWNL

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.

AUTOR1UIP

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.

AUTOR2RWNL

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

AUTOR2WDNL

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

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