User guide

Example
$ thincontrol –poll
6.4.7.3 Multicast Polling
The controller uses multicast polling to discover Oracle JDBC for Rdb servers that may be
available on the network.
Multicasting is a style of efficiently broadcasting data over a network connection to
many connected servers. Any server listening in to the multicast IP address will
receive the data packets that are broadcast, such as poll requests.
Oracle JDBC for Rdb servers use the Administrative Scoping range of addresses that allow
easy limiting of multicast transmission to well defined boundaries within your network.
Administrative Scoping is the restriction of multicast transport based on the address range
of the multicast group. It is defined by RFC 2365
"Administratively Scoped IP Multicast." and is
restricted to the address range:
239.0.0.0 to 239.255.255.255
The IP address for server multicast polling should be chosen from within the following
range:
239.192.0.0 to 239.192.255.255
This range is known as the IPv4 Organization Local Scope and has a subnet mask of
255.252.0.0 It is intended for use by an entire organization setting multicast scopes
privately for its own internal or organizational use and allows up to 262,144 group
addresses.
By default, Rdb servers use the multicast IP 239.192.1.1 with a base port of 5517.
Multicast Group IP addresses can be assigned to a server using the srv.mcGroupIP option
within a server configuration file or the server start-up command line.
The srv.mcBasePort option allows you to change the Multicast Base port.
Note:
When a server participates in a multicast group, as part of the standard multicast protocol
its presence in the group will be broadcast at regular intervals. This may conflict with the
network policy and procedures of your network administration.
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