Rockwell ArmorStratix 5700 series, Инструкция по эксплуатации

Страница: 297 / 548

Rockwell Automation Publication 1783-UM007F-EN-P - September 2016 297
Configure Switch Features Chapter 7
Parallel Redundancy
Protocol (PRP) Stratix 5400 and 5410 switches support PRP as a redundancy box (RedBox).
As a RedBox, PRP sends duplicate packets from two different ports on
independent network paths. The redudant paths provide high availability for
data transmission if one of the paths enounters a failure. For more informatoin
about PRP, see the IEC 62439-3 standard.
Table 76 describes terms to know before you configure PRP.
NTP Association Settings
Status Displays a symbol to indicate the status of the NTP peer association.
* sys.peer
# selected
+ candidate
- outlyer
Configured Displays the status of the NTP peer association.
IP Address Displays the specified IP address for the association:
• For a peer association, the IP address identifies the peer providing, or being
provided, the clock synchronization.
• For a server association, the IP address identifies the time server providing the clock
synchronization.
Prefer If checked, the peer or server is the preferred one that provides synchronization.
Ref Clock Displays a 32-bit code or Internet address that identifies the reference clock of the peer.
Stratum Displays the stratum of the peer.
When Displays the time in seconds since the last NTP packet was received from the peer.
Poll Displays the polling interval in seconds.
Delay Displays the round-trip delay to the peer in milliseconds.
Offset Displays the relative time of the peer clock to the local clock in milliseconds.
Table 75 - NTP Fields (Continued)
Field Description
Table 76 - PRP Terms
Term Description
Dual Attached Node implementing PRP (DANP) End-device with PRP functionality connected to each of the two independent LANs.
Single Attached Node (SAN) Device with a single network interface connected directly to one of the two LANs.
Redundancy Box (RedBox) Device that connects one or more SANs to both LANs. The switch implements RedBox functionality.
Virtual DAN (VDAN) A SAN connected to both LANs through a RedBox. A node behind a RedBox appears to other nodes as a DAN.
PRP channel A logical interface that aggregates PRP groups (access, trunk, or routed) into a single link. The PRP channel remains
up as long as one of its member ports remain up and send traffic. When both member ports are down, the channel is
down. Only the up and down states of the ports can trigger different redundancy behavior or SAN traffic routing
decisions.
Each channel contains two Layer 2 or Layer 3 Gigabit Ethernet interfaces. Within each channel group, the lowest
numbered Gigabit Ethernet interfaces (Gi1/1 and Gi1/3 or Gi1/17 and Gi1/19, depending on the switch) are always
the primary port. The highest numbered Gigabit Ethernet interfaces (Gi1/2 and Gi1/4 or Gi1/18 and Gi1/20,
depending on the switch) are the secondary port.
PRP channel group A group is composed of two ports, one of which represents LAN A and the other LAN B:
• PRP channel group 1 always contains the Gi1/1 and Gi1/2 or Gi1/17 and Gi1/18 interfaces.
• PRP channel group 2 always contains Gi1/3 and Gi1/4 or Gi1/19 and Gi1/20 interfaces.