Grid Management Pages

The Topology Overview Page

The Topology Overview page is the initial Grid Management page that you see. It shows a logical view of the hosts running in the grid and all nodes running on them. The page is intended to give information on all individual runtime artifacts: grid agents, the grid registry, grid routers, and application nodes. Technically, each runtime artifact, except hosts, corresponds to a JVM.

The top of the page displays:

• The name of this instance of the Lawson Grid

• A stop button that lets you stop the grid or applications in the grid

• A link to the status page

• A link to the logging page

• A link to pages showing more advanced details of the grid

• A link to a page with application focus (in contrast to the runtime artifact focus of this page)

For each runtime artifact, the page displays the following:

Column	Description	Comment
Type	The type of runtime entity displayed on a row, for example, host, grid agent, registry, router, or node	For hosts, this column also includes a start button that allows you to start nodes (bindings) on that particular host.
Name	The name of the runtime entity	For nodes, this is the name of the binding used to start the node.
Status	The general status of the entity. Normally this should be "OK," but it may also be "OFFLINE" or "STOPPING."	When a node is off-line, it will take no new requests while letting already processing request finish. For more information on the off-line status, see Putting the Grid or Parts of the Grid in an Off-Line State.
	A stop button for all entities except hosts and grid agents	This is useful when an individual application node needs to be shut down, for example, because it is in an error state.
Id	A unique ID for each runtime artifact.	The ID consists of address, port, and process id.
Log	Link that displays the log file belonging to this runtime artifact	This is the default place to look for information if a node is showing signs of having problems.
Log Status	Number of errors and warnings in the log	View the log for details. If errors or warnings are indicated, the cause should be investigated. When the problems have been taken care of or they have been deemed unimportant or irrelevant, it is possible, and recommended, to reset the loggers using the "Reset Loggers" button at the top of the page. This will reset the error and warning counts to zero so that it is easier to see if new errors appear. It is only the count that is reset. No information is removed from the log files.
Up Time	How long this runtime artifact been running (time since last started)	A short up time could indicate that a node has been automatically restarted due to some problem. Obviously, the short up time could also have a natural explanation.
CPU%	Approximate CPU usage	Different applications use the CPU in different ways. What is normal depends on the application. This information can indicate if an application does not behave as it usually does.
Heap Usage	Memory usage of the runtime artifact (JVM)	Typically application should not be short of memory in order to perform well (there are exceptions).

You can expand hosts so that more information is displayed. To do so, click on the small plus icon to the far left of each host row in the list or click on the Expand All button. When expanded, routers will list information about external addresses and ports used. Nodes will list individual application modules.

At the bottom of the page are links to all applications. If the applications provide management pages of their own, a link to them is also displayed. These links are useful to get more information about a particular application.

The Status Page

This Status page is accessed from a Status link at the top of the Topology Overview page.

The status page is intended to give a condensed view of the status of the grid itself and of each application. The page is constructed so that it only show problems if they exist. This means that the less information that is shown the better it is. Once an application has some form of problem, this will be indicated on this page and the actual problem will have to be investigated using the other management pages. The application names and problems that are displayed often form a link to a page that is relevant to the problem at hand.

The nature of this page makes it suitable when you want a high level view of how the grid and its applications are performing.

The Applications Page

The Applications page is accessed from an Applications link at the top of the Topology Overview page.

This page displays the same information as the Topology Overview page but the information is rearranged with a focus on applications. Normally, an overview of each application is listed. If a particular application is selected, that application is moved to the top of the page and more information about that application is displayed. The detailed information is essentially the same as in the topology overview but only the runtime artifacts that are related to the application are displayed.

This page also provides convenient ways to access the configuration of the applications as well as starting, stopping, and managing the off-line state of the applications.

Landmark contains several application management pages that are useful for monitoring and administering the Landmark system. For more information, see Landmark Management Pages.