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BigIron RX Series Configuration Guide
375
53-1002253-01
Convergence in a simple topology
13
FIGURE 54
Simple Layer 2 topology
The point-to-point connections between the three bridges are as follows:
•
Port2/Switch 1 and Port2/Switch 2
•
Port4/Switch 1 and Port4/Switch 3
•
Port3/Switch 2 and Port3/Switch 3
Ports 3 and 5 on Switch 1 are physically connected together.
At start up, the ports on Switch 1 assume Designated port roles, which are in discarding state. They
begin sending RST BPDUs with proposal flags to move into a forwarding state.
When Port4/Switch 3 receives these RST BPDUs RSTP algorithm determines that they are better
than the RST BPDUs that were previously received on Port3/Switch 3. Port4/Switch 3 is now
selected as Root port. This new assignment signals Port3/Switch 3 to begin entering the discarding
state and to assume an Alternate port role. As it goes through the transition, Port3/Switch 3
negotiates a new role and state with its peer port, Port3/Switch 2.
Port4/Switch 3 sends an RST BPDU with an agreed flag to Port4/Switch 1. Both ports go into
forwarding states.
Port2/Switch 2 receives an RST BPDU. The RSTP algorithm determines that these RST BPDUs that
are superior to any that any port on Switch 2 can transmit; therefore, Port2/Switch 2 assumes the
role of a Root port.
The new Root port then signals all ports on the bridge to start synchronization. Since none of the
ports are Edge ports, they all enter the discarding state and assume the role of Designated ports.
Port3/Switch 2, which previously had a Designated role with a forwarding state, starts the
discarding state. They also negotiate port roles and states with their peer ports. Port3/Switch 2
also sends an RST BPU to Port3/Switch 3 with a proposal flag to request permission go into a
forwarding state.
Switch 2
Switch 3
Switch 1
Port2
Designated
port
Port4
Designated port
Port3
Designated
port
Port3
Designated
port
Port5
Backup port
Port3
Alternate
port
Port2
Root port
Port4
Root port
Bridge priority = 1500
Bridge priority = 2000
Bridge priority = 1000
Содержание BigIron RX Series
Страница 100: ...24 BigIron RX Series Configuration Guide 53 1002253 01 Logging on through the Web Management Interface 2 ...
Страница 192: ...116 BigIron RX Series Configuration Guide 53 1002253 01 Configuring authentication method lists 4 ...
Страница 228: ...152 BigIron RX Series Configuration Guide 53 1002253 01 Enabling WAN PHY mode support 6 ...
Страница 312: ...236 BigIron RX Series Configuration Guide 53 1002253 01 Displaying IP information 7 ...
Страница 356: ...280 BigIron RX Series Configuration Guide 53 1002253 01 Resetting LLDP statistics 9 ...
Страница 402: ...326 BigIron RX Series Configuration Guide 53 1002253 01 Transparent firewall mode 11 ...
Страница 432: ...356 BigIron RX Series Configuration Guide 53 1002253 01 SuperSpan 12 ...
Страница 500: ...424 BigIron RX Series Configuration Guide 53 1002253 01 MRP CLI example 14 ...
Страница 580: ...504 BigIron RX Series Configuration Guide 53 1002253 01 Configuring multicast traffic engineering 18 ...
Страница 591: ...BigIron RX Series Configuration Guide 515 53 1002253 01 Displaying traffic reduction 19 ...
Страница 592: ...516 BigIron RX Series Configuration Guide 53 1002253 01 Displaying traffic reduction 19 ...
Страница 598: ...522 BigIron RX Series Configuration Guide 53 1002253 01 Viewing Layer 2 ACLs 20 ...
Страница 656: ...580 BigIron RX Series Configuration Guide 53 1002253 01 Trunk formation 22 ...
Страница 754: ...678 BigIron RX Series Configuration Guide 53 1002253 01 Displaying RIP filters 24 ...
Страница 814: ...738 BigIron RX Series Configuration Guide 53 1002253 01 Displaying OSPF information 25 ...
Страница 932: ...856 BigIron RX Series Configuration Guide 53 1002253 01 Generalized TTL security mechanism support 26 ...
Страница 980: ...904 BigIron RX Series Configuration Guide 53 1002253 01 Clearing IS IS information 28 ...
Страница 1000: ...924 BigIron RX Series Configuration Guide 53 1002253 01 Using secure copy 30 ...
Страница 1088: ...1012 BigIron RX Series Configuration Guide 53 1002253 01 IP source guard 35 ...
Страница 1108: ...1032 BigIron RX Series Configuration Guide 53 1002253 01 Reading CDP packets 37 ...
Страница 1126: ...1050 BigIron RX Series Configuration Guide 53 1002253 01 Clearing sFlow statistics 39 ...
Страница 1140: ...1064 BigIron RX Series Configuration Guide 53 1002253 01 802 1s Multiple Spanning Tree Protocol 40 ...
Страница 1324: ...1248 BigIron RX Series Configuration Guide 53 1002253 01 Displaying OSPFv3 information 48 ...
Страница 1363: ...BigIron RX Series Configuration Guide 1287 53 1002253 01 Continuous System Monitor 51 ...
Страница 1364: ...1288 BigIron RX Series Configuration Guide 53 1002253 01 Continuous System Monitor 51 ...
Страница 1404: ...1328 BigIron RX Series Configuration Guide 53 1002253 01 Commands That Require a Reload D ...
Страница 1458: ...1382 BigIron RX Series Configuration Guide 53 1002253 01 VSRP E ...