H3C S6850 Series, Руководство по настройке

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8
Device Comparison process
Configuration BPDU on
ports after comparison
Port C1}.
3.
Updates its configuration BPDU.
Port C2 performs the following operations:
1.
Receives the original configuration BPDU of Port B2
{1, 0, 1, Port B2}.
2.
Determines that the received configuration BPDU is
superior to the existing configuration BPDU {2, 0, 2,
Port C2}.
3.
Updates its configuration BPDU.
Device C performs the following operations:
1.
Compares the configuration BPDUs of all its ports.
2.
Decides that the configuration BPDU of Port C1 is the
optimum.
3.
Selects Port C1 as the root port with the configuration
BPDU unchanged.
Based on the configuration BPDU and path cost of the root
port, Device C calculates the configuration BPDU of Port C2
{0, 10, 2, Port C2}. Device C compares it with the existing
configuration BPDU of Port C2 {1, 0, 1, Port B2}. Device C
determines that the calculated configuration BPDU is
superior to the existing one, selects Port C2 as the
designated port, and replaces the configuration BPDU of
Port C2 with the calculated one.
•
Root port (Port C1): {0, 0,
0, Port A2}
•
Designated port (Port C2):
{0, 10, 2, Port C2}
Port C2 performs the following operations:
1.
Receives the updated configuration BPDU of Port B2
{0, 5, 1, Port B2}.
2.
Determines that the received configuration BPDU is
superior to its existing configuration BPDU {0, 10, 2,
Port C2}.
3.
Updates its configuration BPDU.
Port C1 performs the following operations:
1.
Receives a periodic configuration BPDU {0, 0, 0, Port
A2} from Port A2.
2.
Determines that it is the same as the existing
configuration BPDU.
3.
Discards the received BPDU.
•
Port C1: {0, 0, 0, Port A2}
•
Port C2: {0, 5, 1, Port B2}
Device C determines that the root path cost of Port C1 is
larger than that of Port C2. The root path cost of Port C1 is
10, root path cost of the received configuration BPDU (0)
plus path cost of Port C1 (10). The root path cost of Port C2
is 9, root path cost of the received configuration BPDU (5)
plus path cost of Port C2 (4). Device C determines that the
configuration BPDU of Port C2 is the optimum, and selects
Port C2 as the root port with the configuration BPDU
unchanged.
Based on the configuration BPDU and path cost of the root
port, Device C performs the following operations:
1.
Calculates a designated port configuration BPDU for
Port C1 {0, 9, 2, Port C1}.
2.
Compares it with the existing configuration BPDU of
Port C1 {0, 0, 0, Port A2}.
3.
Determines that the existing configuration BPDU is
superior to the calculated one and blocks Port C1 with
the configuration BPDU unchanged.
Port C1 does not forward data until a new event triggers a
•
Blocked port (Port C1): {0,
0, 0, Port A2}
•
Root port (Port C2): {0, 5,
1, Port B2}