Configuring full text search for a server group
Use the following information to understand how full text search (FTS) works and how it is configured in a server group environment.
Overview of how FTS works in a server group
FTS within BMC Remedy Action Request (AR) System is made up of the following primary components:
- FTS core – manages the FTS functionality using Lucene library
- FTS Indexer – part of AR System server
- FTS Searcher – part of AR System server and FTS Plug-in server
- FTS plug-in — a Java plug-in, which runs under the FTS Plugin server to serve search requests from the remote AR System servers (which are not indexer servers) in the server group.
- Index – Lucene index files
As events occur within AR System that cause data to be indexed, the AR System server sends a message to FTS Indexer which then adds, deletes, or updates data within the index. Other events could include a request to search the index.
If AR System server is not the indexer in a server group, the AR System server sends the search request to the FTS plug-in which is running under remote FTS plug-in server on the indexer server (where the index exists). The remote FTS plug-in server returns the search results to AR System server and then the AR System server processes the data accordingly.
If AR System server is the indexer, it performs the search requests locally in the index and then returns the search results to the client.
When you configure a server group for FTS, ensure that the following conditions are met:
- The required number of servers are designated as FTS indexing servers in the server group.
- The FTS indexing server is the AR System server that also has the FTS collection and conf directories located on a local disk.
The FTS indexing server hosts a FTS plug-in server for serving the search requests from the remote AR System servers that are not designated as indexer server.
You can designate a server as the FTS indexing server by ranking it in the AR System Server Group Operation Ranking form. For more information, see Setting failover rankings for servers and operations.
FTS uses only one plug-in server as the reader (searcher). The reader plug-in is installed on the FTS indexing server. Only the designated indexing FTS server has a ranking entry in the AR System Server Group Operation Ranking form. This AR System server acts as FTS indexer and FTS searcher for local search requests. The reader (searcher) FTS plug-in server serves as the searcher for all the other AR System servers in the server group that are not designated as indexing server, so you must configure all other non-indexing servers to connect to the searcher FTS plug-in server instance running on the FTS indexing server. The searcher instance runs on a separate port on the FTS indexing server.
The events that cause data to be written to the index result in data being put into the AR System database as a queue of items to index. Only the FTS indexing server processes index requests from this queue. However, any instance of AR System server can send a search request to its corresponding FTS plug-in. This ensures index integrity. For more information, see FTS plug-in configuration. There is no search fail-over for the indexer AR System server.
- When you perform full text search on a computer, the FTS searcher uses the stop words configured on the corresponding indexer server. The FTS searcher does not use the stop words configured on the computer on which full text search is performed.
- When full text search happens on a computer, the value of the
AR_SERVER_INFO_FT_SUPPORT_EXACT_MATCH_SEARCHconfiguration on the corresponding indexer server is used to perform full text search. The value of this configuration on the computer on which full text search is performed has no role to play in full text search.
Configuring FTS for a server group
If you use FTS in a server group, you can designate more than one server as indexing server in the server group.
Each FTS indexing server has its own virtual queue of data to index. When AR System queues data for indexing in parallel to AR Database changes in data, it queues separately for each FTS Indexing server as designated by the Server Group Ranking form for FTS.
In a server group, the server that owns the full text indexing operation processes all pending indexing tasks regardless of their server of origin. (The other servers have read-only access to the index files.)
FTS is configured after all servers in the group have been installed and configured to run within a server group. It is recommended that the FTS collection directory and the FTS configuration directory be located on the same computer.
To set up FTS in a server group
Rank the FTS servers in the AR System Server Group Operation Ranking form. For more information, see Setting failover rankings for servers and operations.
You should use the FTS indexing server, which is ranked 1 in the AR System Server Group Operation Ranking form, for searching and the other FTS indexing server, which is ranked 2, as the failover server.
- In a browser, open the BMC Remedy AR System Administration Console, and click System > General > FTS Configuration.
- Complete the form as per FTS Configuration form in the AR System Administration Console.