InfoScale™ 9.0 Disaster Recovery Implementation Guide - Linux
- Section I. Introducing Storage Foundation and High Availability Solutions for disaster recovery
- About supported disaster recovery scenarios
- About campus cluster configuration
- About replicated data clusters
- About global clusters
- VCS global clusters: The building blocks
- About global cluster management
- About serialization - The Authority attribute
- Planning for disaster recovery
- About supported disaster recovery scenarios
- Section II. Implementing campus clusters
- Setting up campus clusters for VCS and SFHA
- About setting up a campus cluster configuration
- About running a fire drill in a campus cluster
- About setting up a campus cluster configuration
- Setting up campus clusters for SFCFSHA, SFRAC
- Setting up campus clusters for VCS and SFHA
- Section III. Implementing replicated data clusters
- Configuring a replicated data cluster using VVR
- Configuring a replicated data cluster using third-party replication
- Section IV. Implementing global clusters
- Configuring global clusters for VCS and SFHA
- Setting up VVR replication
- Creating a Replicated Data Set
- Creating a Primary RVG of an RDS
- Adding a Secondary to an RDS
- Changing the replication settings for a Secondary
- Synchronizing the Secondary and starting replication
- Starting replication when the data volumes are zero initialized
- Configuring clusters for global cluster setup
- Configuring service groups for global cluster setup
- Configuring a global cluster with Storage Foundation Cluster File System High Availability, Storage Foundation for Oracle RAC, or Storage Foundation for Sybase CE
- Configuring the secondary site
- Configuring global clusters with VVR and Storage Foundation Cluster File System High Availability, Storage Foundation for Oracle RAC, or Storage Foundation for Sybase CE
- Setting up replication on the primary site using VVR
- Setting up replication on the secondary site using VVR
- Configuring Cluster Server to replicate the database volume using VVR
- Configuring global clusters for VCS and SFHA
- Section V. Reference
- Appendix A. Sample configuration files
- Sample Storage Foundation for Oracle RAC configuration files
- About sample main.cf files for Storage Foundation (SF) for Oracle RAC
- About sample main.cf files for Storage Foundation (SF) for Sybase ASE CE
- Appendix A. Sample configuration files
About serialization - The Authority attribute
VCS ensures that global service group operations are conducted serially to avoid timing problems and to ensure smooth performance. The Authority attribute prevents a service group from coming online in multiple clusters at the same time. Authority is a persistent service group attribute and it designates which cluster has the right to bring a global service group online. The attribute cannot be modified at runtime.
If two administrators simultaneously try to bring a service group online in a two-cluster global group, one command is honored, and the other is rejected based on the value of the Authority attribute.
The attribute prevents bringing a service group online in a cluster that does not have the authority to do so. If the cluster holding authority is down, you can enforce a takeover by using the command hagrp -online -force service_group. This command enables you to fail over an application to another cluster when a disaster occurs.
Note:
A cluster assuming authority for a group does not guarantee the group will be brought online on the cluster. The attribute merely specifies the right to attempt bringing the service group online in the cluster. The presence of Authority does not override group settings like frozen, autodisabled, non-probed, and so on, that prevent service groups from going online.
You must seed authority if it is not held on any cluster.
Offline operations on global groups can originate from any cluster and do not require a change of authority to do so, because taking a group offline does not necessarily indicate an intention to perform a cross-cluster failover.