Comtech EF Data CDD-880, Инструкция по установке и эксплуатации

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E–1
Appendix E. PORT DIVERSITY
E.1 Port Diversity Overview
CAUTION – It is critical for certain system operations that Management Traffic and
Data Traffic remain isolated – there must be a separate subnet for each interface.
Comtech EF Data therefore does not recommend the use of Port Diversity unless it
is used to implement physical link redundancy schemes. Operations that do not use
such physical link redundancy should maintain the physical isolation of
Management Traffic and Data Traffic on different ports.
If you use Port Diversity, you must take great care within your network routing
elements to ensure that there is no mixing between the Management Traffic and
Data Traffic domains.
The CDD-880 Multi Receiver Router uses the Port Diversity feature to create a redundant link to
the unit by assigning the IP Addresses for both the ‘ ETHERNET | TRAFFIC/MANAGEMENT | GE ’
port and the ‘ ETHERNET | TRAFFIC | GE’ port to one of the physical interfaces. Both ports can
be used to route data with Port Diversity disabled – each port will have its own IP Address and
Subnet. Traffic pertaining to that subnet is routed over that interface, and manual routes can be
routed to either port, dependent on the network topology and configuration.
The Port Diversity feature must be used in a setup with multiple (i.e., two or more) switches.
The switches need to be running Spanning Tree Protocol (STP) or Rapid Spanning Tree Protocol
(RSTP).
It is important that STP or RSTP is running when connecting multiple switches, as the redundant
links will cause switching loops, causing devices to stop responding.
STP is automatically enabled by default on Cisco Catalyst Switches. You might need to configure
and enable STP on other switches such as Linksys, Cisco Small Business, D-Link, etc.
Based on the switch environment, the CDD-880 will elect the best path and use that port as the
Active Port to pass data over the two subnets. The Port Diversity feature makes decisions based
on physical link status first; however, if both links are physically up, it will make Active Port
decisions based on Bridge Protocol Data Units (BPDUs) via STP/RSTP.