17.8.1 Common configuration mistakes
Some common HA configuration mistakes are listed here:
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Disk configuration is not valid.
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VCS or SCS: If a resource cannot be probed, there is something wrong with the configuration. If a disk cannot be probed, the disk might no longer be accessible by the operating system.
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Test the disk configuration manually and confirm against HA documentation that the configuration is appropriate.
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The disk is in use and cannot be started for the HA resource group.
Always check that the disk is not activated before starting the HA resource group.
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WSFC network configuration is not valid.
If network traffic is flowing across multiple NIC cards, RDP sessions fail when activating programs that consume a large amount of network bandwidth, such as the NNMi ovjboss process.
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Some HA products do not restart automatically at startup.
Review the HA product documentation for details about how to configure automatic restart at startup.
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NFS or other access is added directly to the OS.
The resource group configuration must manage this behavior.
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Being in the shared disk mount point during a failover or when the HA resource group is being placed offline.
HA kills any processes that prevent the shared disk from being unmounted.
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Reusing the HA cluster virtual IP address as the HA resource virtual IP address.
This works on one system and not the other.
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Timeouts are too frequent.
If the products are misbehaving, the HA product might timeout the HA resource and cause a failover.
In WSFC, check the value of the Time to wait for resource to start setting. NNMi sets this value to 15 minutes, but you can increase it.
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Maintenance mode is not being used.
Maintenance mode was created for debugging HA failures. If you attempt to bring a resource group online on a system and it fails over shortly thereafter, use the maintenance mode to keep the resource group online to see what is failing.
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Cluster logs are not being used.
Cluster logs can show many common mistakes.