Replication checks

When you set up and test replication, be aware of:

• What the replica server checks at startup

• Guidelines for special situations

For replication checks:

• Replica A Helix Core Server that automatically maintains a full or partial copy of the master server's metadata and that might contain related file content. The replica copies from its master by using 'p4 pull' or 'p4 journalcopy'. A replica can be used as a backup server for disaster recovery. refers to Edge Servers as well as replica servers.

• Master server The innermost Helix Core server in a multi-server topology. A commit server can also be referred to as a master server. refers to the server that is the target server, which is established by the replica's P4TARGET environment variable.

What the replica server checks at startup

When a replica server is started, it checks to ensure the setting of its lbr.replication configurable is correct for the environment in which it is running. If the setting of lbr.replication is incompatible with the storage in the environment, the replica's log file indicates the error:

The replica's pull or journalcopy thread checks whether its depots are shared with its master server. (The exceptions to this rule are that Archive depots and Remote depots are not checked because they are not routinely replicated.)

How the replica checks for shared storage at startup

To check for shared storage at startup, the replica uses temporary binary files in the format described at Versioned file formats.

1. The replica creates a temporary binary file in each of its depots with the format:
   

   depot-name/PerforceServerIdentities/server-id,d/1.1
   For example,

   Project1/PerforceServerIdentities/EdgeServer3,d/1.1

   where Project1 is a depot, PerforceServerIdentities is the specific directory used for this check, and EdgeServer3,d/1.1 is the binary file storage for the EdgeServer3 file that identifies this replica.

2. The replica requests that the master server check if it can locate this file in each of its depots.

3. When the checks are done, the replica deletes the PerforceServerIdentities directory and its contents.

Guidelines for special situations

When setting up and testing replication, consider these guidelines:

                            p4 -F "%name% %map%" -ztag depots
p4 -F "%name% %map%" -ztag depots -t graph
p4 -F "%name% %map%" -ztag depots -t extension