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

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CDD-880 Multi Receiver Router MN-CDD880
Appendix E Revision 2
E–3
The Virtual Router Redundancy Protocol (VRRP) eliminates the single point of
failure inherent in the static default routed environment.
A switch running STP/RSTP may take longer than 30 seconds to allow a port to forward traffic.
Ports connected to the CDD-880 should be designated as Edge Ports, or use Portfast if using a
Cisco switch, to minimize downtime during a switch. Figure E-2 shows a three-switch setup
example, where Links L1 , L2 , L4 , and L5 are Edge Ports.
Figure E-2. Port Diversity Example #2 – Three-Switch Setup
Once the switches are configured to run STP/RSTP, a Root switch is elected, and Port Diversity is
enabled; both the Data Traffic ( GE DATA ) and Management Traffic ( GE MGMT ) IP Addresses of
the CDD-880 will be multi-homed to the chosen path’s interface. When a physical path is chosen
or changed, the CDD880 will issue Gratuitous ARP for both subnets to update the ARP/MAC
tables of local network elements.
The CDD-880 HTTP Interface is accessible from either
configured IP Address.
Using this setup, Switch #3 has the lowest priority (Root); Switch #1 ’s priority is a higher number
than Switch #3 , but lower than Switch #2 . Alternately, the same setup is achievable by setting
the path cost to the Root lower on Switch # 1 than on Switch #2 . This setup responds to changes
in Links L4 and L5 . For example, if Link L4 is down, the CDD-880 will switch to Link L2 , as the path
to the Root is better.
Figure E-3. Port Diversity Example #3 – Two-Switch Setup