Server Health Tool
This tool is available for versions of Weave from 2.5.20.
The Server Health Tool opens a window that shows you the status of the components of your Weave installation - Data Sources, Map Engines and Spatial Engines.
The Status column can be:
- OK = The item is working as expected.
- WARN = The item is not currently available, but it's not necessarily failed yet.
- CRITICAL = The item has failed and is not currently available.
Sample Server Health Output
As an example of how the item status works imagine that we have an attribute search that requires a database connection before it can be used. During startup Weave reads the current configuration and processes both the attribute search and the database connection that it relies upon at the same time. The attribute search can not be said to be available until it knows that the database it's associated with is alive and accepting connections, but database connections can take a number of seconds to become available. During this period both the attribute search and the database connection will have a status of WARN, since we don't know if there's a problem establishing the database connection or if it's just taking time to establish the connection.
If the database connection is eventually successfully established then the new connection will be registered with Weave and the database's connection status will change to OK. Additionally, since the attribute search has been waiting on the database connection to be established before it can be registered, it now changes its status to OK and is also registered with the system.
If however the database connection fails, either because the database is down or because the connection was not configured correctly, then the database's connection status will change to CRITICAL and the database connection will not be registered with Weave. At this stage the attribute search will still be listed as WARN, because it's still waiting on the database connection to be available, however the attribute search is setup with a timeout to ensure that if it waits too long for the database connection then it to will change to CRITICAL.
If the problem with the database was a temporary one and the database comes back on-line, then the status of the database connection should change to OK and attribute search should detect the availability of the database connection that it's relying upon and also change to OK. And if the database goes down again, the database connection status will change to CRITICAL and it will be unregistered, the attribute report will detect the loss of its database connection and change to WARN until it times out and then will switch to CRITICAL too, unless the database comes back on-line within the timeout period.