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Product: Cluster Server Enterprise Agents Guides   
Manual: Cluster Server 4.1 Enterprise Agent for Hitachi TrueCopy Installation and Configuration Guide   

Agent Operations

The Hitachi TrueCopy agent performs the following operations:

Operation (Entry Point) Description

online

If the state of all local devices is read-write enabled, the agent creates a lock file on the local host to indicate that the resource is online. This makes the devices writable for the application.

If one or more devices are not in a writable state, the agent runs the horctakeover command to enable read-write access to the devices:

  • For S-VOL devices in any state other than SSWS or SSUS, the agent runs the horctakeover command and makes the devices writable. The time required for failover depends on the health of the original primary and the RAID Manager timeouts defined in the horcm configuration file for the device group.
  • The agent considers P-VOL devices writable and takes no action other than going online, regardless of their status.
  • If S-VOL devices are in the COPY state, the agent waits until the synchronization from the primary has completed before running the horctakeover command or until the OnlineTimeout period of the entry point has expired, in which case the resource faults.

offline

The agent removes the lock file on the device. The agent does not run any TrueCopy commands because taking the resource offline is not indicative of an intention to give up the devices.

monitor

Verifies the existence of the lock file to determine the resource status. If the lock file exists, the agent reports the status of the resource as online. If the lock file does not exist, the agent reports the status of the resource as offline.

The monitor entry point does not examine the state of the devices or the state of the replication link between the arrays.

open

Removes the lock file on the system on which this entry point is called. This prevents potential concurrency violation if the group fails over to another node.



Note    The agent does not remove the lock file if the agent was started after an hastop -force command.

clean

Determines whether if it is safe to fault the resource if the online entry point fails or times out. The main consideration is whether a management operation was in progress when the online thread timed out and was killed, potentially leaving the devices in an unusable state.

info

Reports the current role and status of the devices in the device group. This entry point can be used to verify the device state and to monitor dirty track trends.

action

Resynchronizes devices from the VCS command line after various connectivity failures are detected and corrected.

The agent supports the following actions:

  • pairdisplay---Displays information about all devices.
  • pairresync---Resynchronizes the S-VOLs.
  • pairresync-swaps---Promotes the S-VOLs to P-VOLs and resynchronizes the original P-VOLs.
  • localtakeover---Makes the local devices write-enabled.
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Product: Cluster Server Enterprise Agents Guides  
Manual: Cluster Server 4.1 Enterprise Agent for Hitachi TrueCopy Installation and Configuration Guide  
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