You can run servers in Admin mode to perform maintenance on the server without allowing connections from your application end users. In Admin mode, the server accepts connections from EAServer Manager, jagtool, and clients that set the admin ORB option (described further below). A server that is accepting regular client connections is said to be in Ready mode.
In some cases, a server may switch to Admin mode when starting if a configuration problem prevents normal operation. For example:
The server is in a cluster, and its cluster version and start-up mode properties indicates that the configuration is not synchronized with the master configuration. In this case, you must synchronize the cluster as described in “Synchronization”.
The message service is installed, but cannot start for some reason such as failure to connect to the remote database server that stores message data. In this case, you must correct the configuration problem as described in Chapter 8, “Setting up the Message Service.”
When the server starts in Admin mode, or switches to Admin mode, it logs a message like this:
The server is in "admin" mode (reason).
where reason is text that describes why the server is in Admin mode. You see a similar message in EAServer Manager when you connect to a server running in Admin mode. With jagtool, you can check whether the server is in Admin mode with the getserverinfo command. In a custom management client, you can call the Jaguar::Management::getStatus() method: a return value of “ready” indicates normal operation. Any other value is text describing the reason the server is in Admin mode.
You can manually switch servers to Admin mode using any of the following techniques:
Using jagtool and running the set_admin and restart commands.
Using a custom management client that calls the setAdmin and restart methods in the Jaguar::Management API.
The server must be restarted to run in Admin mode. You can specify your own reason when placing the server in Admin mode.
You can switch a server from Admin mode to Ready mode using any of the following techniques:
Using EAServer Manager, by connecting to the server, highlighting the server icon, and choosing File | Set Ready.
Using jagtool, by running the set_ready commands.
Using a custom management client, by calling the setReady method in the Jaguar::Management API.
By deleting the file <servername>.admin in the Repository/Server subdirectory of the EAServer installation, where <servername> is the server name and restarting the server.
Unless you manually delete the <servername>.admin file, the server does not require a restart to switch to Ready mode; it begins accepting regular client connections immediately. If the configuration that you performed requires a server restart, do it before switching to Ready mode.
A server that is in Admin mode refuses connections from normal clients. To create clients that connect to the server running in Admin mode, you must set the admin ORB option for your client type as described in Table 3-20.
Admin mode clients can call any components installed in the server, subject to the standard role-based security restrictions. However, the server accepts Admin mode connections before all normal initialization has completed. Therefore, keep in mind the following caveats when creating or running Admin mode clients:
Service components may not have finished starting. You can check the status of installed services using the jagtool getservicestate command or by reading the service status messages in the server log file.
If the server is in a cluster, it may not have joined the cluster.
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