@@ -8046,33 +8046,33 @@ availability and performance tuning. For example the database's
80468046
80478047Users of [Oracle Database FAN][64] should set
80488048[`oracledb.events`](#propdbevents) to *true*. This can also be
8049- enabled via [Oracle Client Configuration](#oraaccess).
8049+ enabled via [Oracle Client Configuration](#oraaccess). Your
8050+ application must connect to a FAN-enabled database service.
80508051
8051- FAN support gives fast connection failover, an Oracle Database high
8052- availability feature. This allows applications to be notified when a
8053- database machine becomes unavailable . Without FAN, node-oracledb can
8052+ FAN support is useful for planned and unplanned outages. It provides
8053+ immediate notification to node-oracledb following outages related to
8054+ the database, computers, and networks . Without FAN, node-oracledb can
80548055hang until a TCP timeout occurs and an error is returned, which might
8055- be several minutes. Enabling FAN in node-oracledb can allow
8056- applications to detect errors, re-connect to an available database
8057- instance, and replay application logic without the application user
8058- being aware of an outage. It is up to the application to handle
8059- errors and take desired action.
8056+ be several minutes.
8057+
8058+ FAN allows node-oracledb to provide high availability features without
8059+ the application being aware of an outage. Unused, idle connections in
8060+ a connection pool will be automatically cleaned up. A future
8061+ `pool.getConnection()` calls will establish a fresh connection to a
8062+ surviving database instance without the application being aware of any
8063+ service disruption.
8064+
8065+ To handle errors that affect active connections, you can add
8066+ application logic to re-connect (this will connect to a surviving
8067+ database instance) and replay application logic without having to
8068+ return an error to the application user.
80608069
80618070FAN benefits users of Oracle Database' s clustering technology ([Oracle
80628071RAC ][93 ]) because connections to surviving database instances can be
8063- immediately made . Users of Oracle' s Data Guard with a broker will see
8064- the FAN events generated when the standby database goes online.
8072+ immediately made . Users of Oracle' s Data Guard with a broker will get
8073+ FAN events generated when the standby database goes online.
80658074Standalone databases will send FAN events when the database restarts.
80668075
8067- For active connections, when a machine or database instance becomes
8068- unavailable, a connection failure error will be returned by the
8069- node-oracledb method currently being called. On a subsequent
8070- re-connect, a connection to a surviving database instance will be
8071- established. Node-oracledb also transparently cleans up any idle
8072- connections affected by a database machine or instance failure so
8073- future connect calls will establish a fresh connection without the
8074- application being aware of any service disruption.
8075-
80768076For a more information on FAN see the [whitepaper on Fast Application
80778077Notification][97].
80788078
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