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MckoiDDB Console Reference

The MckoiDDB Console is an interface for performing administrative functions on a MckoiDDB installation. The following Java command will start the console given the location of the network.conf file and the network password;

java -cp mckoiddb.jar com.mckoi.runtime.AdminConsole -netconfig [network.conf] -netpassword [network password]

The console application must be run from a machine that has an IP address included in the connect_whitelist property of the network.conf file. The location of the network.conf file may be on web server, in which case a URL is given (such as '').

Console commands can also be piped to the console application to automate commonly used commands (for example, for initial setup of a database).

Console Commands Reference

The following commands are provided by the Console;

show network

Displays the list of machines in the network schema and the roles they are assigned to perform. If a machine is down or otherwise unavailable, an access error is reported.

show paths

Displays the location and status of all paths in the system.

show status

Displays information on machine status. This command will show if the machine is unavailable, or any other status information about the machine currently recorded by the manager server.

show free

Displays an overview of all machine resources currently available, including the amount of heap used by the Machine Node and the amount of disk space used and available.

start role [block/manager/root] on [address]

Starts either a block server, manager server or root server role on the machine at the given address. A Machine Node may operate any combination of these three roles, however, only one manager server may be assigned over the whole network.


start role block on

stop role [block/manager/root] on [address]

Stops either a block server, manager server or root server role on the machine at the given address.


stop role block on

move manager to [address]

Moves the manager service to the given machine. Currently not implemented.

add path [consensus function] [path name] to [address of root]

Adds a new path name and consensus function on the given root server.


add path com.mckoi.sdb.SimpleDatabase mysimpledb to

add simple database [path name] to [address of root]

Adds a simple database (com.mckoi.sdb.SimpleDatabase) path name on the given root server.


add simple database mysimpledb to

remove path [path name]

Removes a path from the root server that is managing it.


remove path mysimpledb

locate path [path name]

Reports the root server address of the machine currently managing the given path.


Forces a refresh of any information stored in the console interface regarding the network status. This command is useful when you know the status of a machine has changed and you want to ensure the console picks up the change.

check network

Performs a check on the block files stored in the MckoiDDB network, reporting the following problems;

  1. There are less than three machine nodes assigned as Block Server currently available.
  2. Less than three copies of a block are stored over the network and more that three machine nodes are available.
  3. The information the manager server has on block availability is not in sync with what the block servers report they have available.

fix block availability

Fixes problems reported by the check network command, provided the problem can be fixed.

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