Failover error handling
Windows Cluster automatically fails over resource groups if the system where resource group is running on becomes unavailable. This is part of the cluster functionality. Also, this means that if a problem occurs with the HP 3PAR storage system, a resource group online process will be stopped. The behavior of HP 3PAR Cluster Extension is highly configurable. Depending upon the customer setting, Cluster Extension is used to prevent resource groups from going online automatically under the wrong conditions.
Cluster Extension will return local, data
HP 3PAR Cluster Extension services, resources, or resource groups return a data center error and fail the resource if the Remote Copy volume group status indicates that the problem experienced locally would not be solved on another system connected to the same HP 3PAR storage system.
Depending on the resource group and resource property values, the resource tries to start on different nodes several times. If the remote data center is down, this would look like the resource group is alternating between the surviving systems. This happens until the previously mentioned resource and resource group property values are reached or you disable the restarting of the resource. This could be also the case if the ApplicationStartup resource property has been set to FASTFAILBACK. If a 3PAR storage system state has been discovered that does not allow bringing the resource group online on any system in the cluster, a cluster error would be reported and the resource would fail on all systems. This could lead to the same behavior as described for a HP 3PAR Cluster Extension data center error.
Failing physical disk resources during online attempt of the resource group
When resource groups that use HP 3PAR Cluster Extension to failover Remote Copy volume group are brought online, physical disk resources may fail due to the following reasons:
•The physical disk resource does not have a dependency on its HP 3PAR Cluster Extension resources/packages configured. Review the setup steps for HP 3PAR Cluster Extension resources.
•The fibre channel path or connectivity between the servers and the storage systems may be broken. So user has to review the FC connectivity between the servers and the storage systems.
•If the storage array is brought back online or started after the array shutdown due to the datacenter disaster or Inform OS upgrade, at times the status of the remote copy volume group may go to the failsafe status as soon as the array is brought back online. The status of the remote copy volume group is marked as failsafe by the Inform OS after the array comes online and when the replication roles are primary at one side and
One of the scenarios to get in to the failsafe status can be explained as follows.
The replication roles for a remote copy volume group are primary in one datacenter (primary) and secondary in the other datacenter (secondary) and the corresponding application in the Microsoft failover cluster are online in the primary datacenter. In case a disaster such as power outage happens in the primary datacenter, the application tries to failover to the failover cluster host in the secondary datacenter. The application comes online successfully in the failover cluster host in the secondary datacenter if the CLX property UseNonCurrentDataOk is set to Yes. Once application comes online, the replication role in the secondary datacenter turns to
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