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ISS Cell - Field HelpEdit any of the following settings on the ISS Cell panel and click Update Configuration. Heart beats per update (local cell only)Accepts a non-negative integer that indicates the number of heartbeats after which ISS will determine whether a domain name server update or a Dispatcher update is required. This allows you to configure an update interval that is relatively large while using a relatively fast heartbeat, so that the well-being of the top-ranked server is checked frequently, but without putting too much load on the name server by updating it too often. The update interval is determined from the product of HeartbeatInterval and HeartbeatsPerUpdate. You can use this field to optimize the overall responsiveness of the service in specific user workload scenarios. For example, to prevent the name server updates from occurring more frequently than once every three heartbeats, enter in the field: HeartbeatsPerUpdate 3 In this example, if HeartbeatInterval is 10 seconds, you have limited the frequency of updates of the name server or the Dispatcher to once every 30 seconds. If this keyword is not specified, the HeartbeatsPerUpdate factor will default to a value of 3. Heart beat interval (local cell only)Indicates the time in seconds that the ISS monitor allows to elapse before it checks the well-being of the nodes configured in that cell. At every heartbeat, ISS checks that each server is functional by issuing an ICMP ping command; this is the same as if you enter ping at a Unix or NT command prompt. While this does not test the state of everything on the server, it does at least ensure that the server is reachable at the IP level. If the server fails to respond, ISS will not recommend it. If you have configured one or more metrics, the ISS agent for each node will send out load information at each heartbeat interval, which allows the ISS monitor to determine the load on each server in the cell, and, if necessary, to remove a node from the recommended list. For example, to initiate a heartbeat every 30 seconds, enter the following: HeartbeatInterval 30 If this keyword is not specified, the heartbeat interval will default to 10 seconds. Heart beats to net fail (local cell only)The number of heartbeats after which a node will be regarded as unreachable and will not be recommended; it will, however, continue to be regarded as running. Heart beats to node fail (local cell only)The number of heartbeats after which a node is considered to have failed completely. HeartbeatsToNodeFail must be equal to or greater than HeartbeatsToNetFail. ISS will still heartbeat to a failed node. The failed status means packets and service updates will no longer be routed to a failed node, and if the failed node is (was) the monitor, then an election will be held. Because there is still a heartbeat ping being sent to a failed node, if it returns to life it will be brought back into the cell. Port numberThe port number currently in active use by ISS for inter-ISS node communication. If you modify the port number on this Cell panel, the change will take effect and be reflected on the Host panel after the ISS daemon is stopped and restarted.If this keyword is not specified, the port number will default to 7139. Ping cache (local cell only)Specifies that ISS should limit the size of the ping triangulation cache to the number of kilobytes specified. If ping cache is set to 0, ping triangulation will not operate in that cell. The default is 0. Authentication key (local cell only)This is a default authentication key that will be used by nodes that do not have have their own authentication key specified. Authentication key is used internally for security in inter-ISS node communications. The authentication key is passed in all communications between nodes. The receiving node verifies that the received authentication key is the authentication key expected from that node. For convenience, the HexString may be broken up by white space as long as it all fits on one line, and as long as every digit is paired off so the parser may read a byte (two characters) at a time. The maximum length is 40 hex characters. If no keyword is specified, the authentication will default to a value of all 0s. The following information is also displayed on the ISS Cell panel: Cell nameA unique identifier for the cell. Local or Global cellIndicates whether the cell is the local cell or a separate, global (remote) cell configured for ping triangulation. For global cells there is a limited set of configurable attributes. There must be 1 and only 1 local cell in a configuration. Note: Adding or deleting sub cell entities for a global cell should be limited to:
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