Networking

插入 SFP 後,Cisco 3850 所有埠都變為琥珀色

  • June 1, 2018

我們用 WS-C3850-24T(堆疊模式下的數量:2)替換了舊的 3750 交換機。每當我插入任何 SFP 模組來連接我們的不同部門時,所有埠都會變成琥珀色幾秒鐘,在此階段,其他埠的所有連接都會斷開,幾秒鐘後所有埠都會恢復綠色並恢復連接。這在舊的 3750 交換機中從未發生過。可能的原因是什麼?

以下是 STP 詳細資訊。

xxx-NOC-3850-Cluster#show spanning-tree summary
Switch is in rapid-pvst mode
Root bridge for: none
Extended system ID           is enabled
Portfast Default             is disabled
PortFast BPDU Guard Default  is disabled
Portfast BPDU Filter Default is disabled
Loopguard Default            is disabled
EtherChannel misconfig guard is enabled
UplinkFast                   is disabled
BackboneFast                 is disabled
Configured Pathcost method used is short

Name                   Blocking Listening Learning Forwarding STP Active
---------------------- -------- --------- -------- ---------- ----------
VLAN0001                     0         0        0         28         28
---------------------- -------- --------- -------- ---------- ----------
1 vlan                       0         0        0         28         28

以下是庫存輸出:

   XXX-NOC-3850-Cluster#sh inv

NAME: "c38xx Stack", DESCR: "c38xx Stack"
PID: WS-C3850-24T     , VID: V07 , SN: FOC2126L0T1

NAME: "Switch 1", DESCR: "WS-C3850-24T-S"
PID: WS-C3850-24T-S   , VID: V07 , SN: FOC2126L0T1

NAME: "StackPort1/1", DESCR: "StackPort1/1"
PID: STACK-T1-50CM   , VID: V01 , SN: MOC2102A2VN

NAME: "Switch 1 - Power Supply B", DESCR: "Switch 1 - Power Supply B"
PID: PWR-C1-350WAC   , VID: V02 , SN: LIT20462TNP

NAME: "Switch 1 FRU Uplink Module 1", DESCR: "4x1G Uplink Module"
PID: C3850-NM-4-1G   , VID: V01 , SN: FOC21083GDN

NAME: "GigabitEthernet1/1/1", DESCR: "1000BaseSX SFP"
PID:                   , VID:     , SN: FNS12060A5K

NAME: "GigabitEthernet1/1/4", DESCR: "1000BaseSX SFP"
PID:                   , VID:     , SN: FNS17041183

NAME: "Switch 2", DESCR: "WS-C3850-24T-S"
PID: WS-C3850-24T-S   , VID: V07 , SN: FCW2113C1AK

NAME: "StackPort2/1", DESCR: "StackPort2/1"
PID: STACK-T1-50CM   , VID: V01 , SN: MOC2102A2VN

NAME: "Switch 2 - Power Supply B", DESCR: "Switch 2 - Power Supply B"
PID: PWR-C1-350WAC   , VID: V02 , SN: ART2205FCLN

NAME: "Switch 2 FRU Uplink Module 1", DESCR: "4x1G Uplink Module"
PID: C3850-NM-4-1G   , VID: V01 , SN: FOC21065HC4

NAME: "GigabitEthernet2/1/1", DESCR: "1000BaseSX SFP"
PID:                   , VID:     , SN: FNS17041321

NAME: "GigabitEthernet2/1/4", DESCR: "1000BaseSX SFP"
PID:                   , VID:     , SN: FNS17041205

如果您的使用者埠未處於 portfast 模式(預設情況下,如 所示Portfast Default is disabled,或每個埠),那麼當生成樹收斂時,您將遇到中斷。

建議使用者埠設置如下,以盡量減少對 STP 的影響:

switchport mode access
switchport access vlan ###
spanning-tree portfast

如果您不想spanning-tree portfast在每個介面上鍵入,則可以spanning-tree portfast default在全域配置模式下將所有訪問埠設置為 portfast 模式。

也不建議使用 Vlan 1,因為它通常未被標記,並且被 Cisco 用於值得與使用者流量分開的網路管理功能。

引用自:https://serverfault.com/questions/913971