Re: 問題ID: 13725 STP
arashi1977
居住地: 広島
投稿数: 1715
引用:ここで表示されるコストは、「自分自身のインタフェースのコスト」ですので、コストをいじってなければデフォルトの19が表示されるんですね。
実機でやってみるとこんな感じです。
この状態で、VLAN50だけコスト値をいじってみると
こうなります。パスコストが表示されるのは詳細表示指定した時ですが、この辺はCCNP SWITCHで問われた…かなぁ?
上記画像で、VLAN0050のCostが19になっていますが、なぜ他のVLANでのCostと同じ19なのですか?
実機でやってみるとこんな感じです。
SW1#show running-config interface FastEthernet 0/1
Building configuration...
Current configuration : 94 bytes
!
interface FastEthernet0/1
switchport trunk encapsulation dot1q
switchport mode trunk
end
SW1#show spanning-tree interface FastEthernet 0/1
Vlan Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
VLAN0001 Desg FWD 19 128.3 P2p
VLAN0010 Desg FWD 19 128.3 P2p
VLAN0030 Desg FWD 19 128.3 P2p
VLAN0050 Desg FWD 19 128.3 P2p
SW1#conf t
Enter configuration commands, one per line. End with CNTL/Z.
SW1(config)#interface FastEthernet 0/1
SW1(config-if)#spanning-tree vlan 50 cost 100
SW1(config-if)#end
SW1#show spanning-tree interface FastEthernet 0/1
Vlan Role Sts Cost Prio.Nbr Type
------------------- ---- --- --------- -------- --------------------------------
VLAN0001 Desg FWD 19 128.3 P2p
VLAN0010 Desg FWD 19 128.3 P2p
VLAN0030 Desg FWD 19 128.3 P2p
VLAN0050 Desg FWD 100 128.3 P2p
SW1#show spanning-tree interface FastEthernet 0/1 detail
Port 3 (FastEthernet0/1) of VLAN0001 is designated forwarding
Port path cost 19, Port priority 128, Port Identifier 128.3. ←ここはポートのコスト
Designated root has priority 24577, address b4a4.e38e.f300
Designated bridge has priority 24577, address b4a4.e38e.f300
Designated port id is 128.3, designated path cost 0 ←ここがパスコスト
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
Link type is point-to-point by default
BPDU: sent 380, received 93
Port 3 (FastEthernet0/1) of VLAN0010 is designated forwarding
Port path cost 19, Port priority 128, Port Identifier 128.3. ←ここはポートのコスト
Designated root has priority 24586, address b4a4.e38e.f300
Designated bridge has priority 24586, address b4a4.e38e.f300
Designated port id is 128.3, designated path cost 0 ←ここがパスコスト
Timers: message age 0, forward delay 0, hold 0
Number of transitions to forwarding state: 1
Link type is point-to-point by default
BPDU: sent 379, received 51
Port 3 (FastEthernet0/1) of VLAN0030 is designated forwarding
Port path cost 19, Port priority 128, Port Identifier 128.3.
(略)
投稿ツリー
-
問題ID: 13725 STP
(fjwrsch1203, 2016-2-21 21:51)
- Re: 問題ID: 13725 STP (arashi1977, 2016-2-22 9:54)