我有一个非常奇怪的问题，我希望有人能够给我一个什么样子的想法。 我有一个新的Netgear M4100-D10-POE第2层pipe理型交换机，我们正在远程安装。 它通过CAT5电缆连接到外部networking的其余部分连接到思科交换机（我们有几个，它连接的地方似乎不重要）。 现在，它工作正常，除了当我断开这个Netgear交换机（或从networking上拔下它）时，我收到来自各种服务的一堆电子邮件，表明一对其他Cisco交换机（Catalyst 3560和一个Catalyst 2960S）。 这些交换机通过光纤线路相互连接。
奇怪的是，Netgear交换机没有直接连接到两个交换机中的任何一个出现链路故障。 两者之间可以有1个或2个其他Cisco交换机。 我也没有看到任何交换机上的任何sorting端口向上/向下的日志消息。 我也知道这不是巧合，因为我可以随时通过插拔Netgear交换机来重新创build问题。
我唯一的猜测是它与BGP，STP或其他一些交换机到交换机协议有关，但我不知道如何监视这个。
更新：这是configuration文件。 首先是Netgear交换机：
!Current Configuration: ! !System Description "M4100-D10-POE ProSafe 10-port FastEthernet L2+ Intelligent Edge PoE Desktop Managed Switch, 10.0.1.28, B1.0.0.9" !System Software Version "10.0.1.28" !System Up Time "2 days 23 hrs 58 mins 15 secs" !Additional Packages QOS,IPv6 Management,Routing !Current SNTP Synchronized Time: Mar 9 19:09:41 2015 UTC ! network protocol none network parms 172.16.112.68 255.255.240.0 172.16.112.4 vlan database vlan 3-10,200 vlan name 3 "VOIP_HD" vlan name 4 "CAMERA" vlan name 5 "WIFI_MGMT" vlan name 6 "WIFI_GUEST" vlan name 7 "WIFI_DATA" vlan name 8 "SAN_SATA" vlan name 9 "SAN_SAS" vlan name 10 "DMZ" vlan name 200 "AUTOVOIP" exit ip ssh server enable ip ssh protocol 2 no ip telnet server enable configure sntp server "172.16.112.6" sntp server "0.north-america.pool.ntp.org" 2 sntp server "1.north-america.pool.ntp.org" 3 time-range ip domain name "caymanport.com" ip name server 172.16.112.6 172.16.112.23 172.16.112.9 snmptrap "CIPAread" ipaddr 172.16.112.65 voice vlan no green-mode energy-detect line console no transport input telnet exit line telnet exit line ssh exit snmp-server sysname "CDCParts1Switch" snmp-server location "CDC Taylor Parts Container" snmp-server contact "IT Manager" ! no snmp-server community public no snmp-server community private auto-voip vlan 200 interface 0/7 vlan participation include 2-3 vlan tagging 2-3 exit interface 0/8 vlan participation include 2-3 vlan tagging 2-3 exit interface 0/9 vlan participation include 2-10 vlan tagging 1-10 exit interface 0/10 vlan participation include 2-10 vlan tagging 1-10 exit no isdp run no isdp advertise-v2 exit 现在Cisco 3560交换机（CDCVOIPSwitch）：
Current configuration : 19392 bytes ! ! Last configuration change at 11:31:57 EST Fri Mar 6 2015 ! NVRAM config last updated at 15:35:31 EST Tue Mar 3 2015 ! version 12.2 no service pad service timestamps debug uptime service timestamps log datetime service password-encryption service sequence-numbers ! hostname CDCVoipSwitch ! boot-start-marker boot-end-marker ! aaa new-model ! aaa session-id common clock timezone EST -5 system mtu routing 1500 ip routing ip domain-name caymanport.com ip name-server 172.16.112.6 ip name-server 172.16.112.23 ip name-server 172.16.112.9 ! mls qos map cos-dscp 0 8 16 26 32 46 48 56 mls qos srr-queue input bandwidth 90 10 mls qos srr-queue input threshold 1 8 16 mls qos srr-queue input threshold 2 34 66 mls qos srr-queue input buffers 67 33 mls qos srr-queue input cos-map queue 1 threshold 2 1 mls qos srr-queue input cos-map queue 1 threshold 3 0 mls qos srr-queue input cos-map queue 2 threshold 1 2 mls qos srr-queue input cos-map queue 2 threshold 2 4 6 7 mls qos srr-queue input cos-map queue 2 threshold 3 3 5 mls qos srr-queue input dscp-map queue 1 threshold 2 9 10 11 12 13 14 15 mls qos srr-queue input dscp-map queue 1 threshold 3 0 1 2 3 4 5 6 7 mls qos srr-queue input dscp-map queue 1 threshold 3 32 mls qos srr-queue input dscp-map queue 2 threshold 1 16 17 18 19 20 21 22 23 mls qos srr-queue input dscp-map queue 2 threshold 2 33 34 35 36 37 38 39 48 mls qos srr-queue input dscp-map queue 2 threshold 2 49 50 51 52 53 54 55 56 mls qos srr-queue input dscp-map queue 2 threshold 2 57 58 59 60 61 62 63 mls qos srr-queue input dscp-map queue 2 threshold 3 24 25 26 27 28 29 30 31 mls qos srr-queue input dscp-map queue 2 threshold 3 40 41 42 43 44 45 46 47 mls qos srr-queue output cos-map queue 1 threshold 3 5 mls qos srr-queue output cos-map queue 2 threshold 3 3 6 7 mls qos srr-queue output cos-map queue 3 threshold 3 2 4 mls qos srr-queue output cos-map queue 4 threshold 2 1 mls qos srr-queue output cos-map queue 4 threshold 3 0 mls qos srr-queue output dscp-map queue 1 threshold 3 40 41 42 43 44 45 46 47 mls qos srr-queue output dscp-map queue 2 threshold 3 24 25 26 27 28 29 30 31 mls qos srr-queue output dscp-map queue 2 threshold 3 48 49 50 51 52 53 54 55 mls qos srr-queue output dscp-map queue 2 threshold 3 56 57 58 59 60 61 62 63 mls qos srr-queue output dscp-map queue 3 threshold 3 16 17 18 19 20 21 22 23 mls qos srr-queue output dscp-map queue 3 threshold 3 32 33 34 35 36 37 38 39 mls qos srr-queue output dscp-map queue 4 threshold 1 8 mls qos srr-queue output dscp-map queue 4 threshold 2 9 10 11 12 13 14 15 mls qos srr-queue output dscp-map queue 4 threshold 3 0 1 2 3 4 5 6 7 mls qos queue-set output 1 threshold 1 138 138 92 138 mls qos queue-set output 1 threshold 2 138 138 92 400 mls qos queue-set output 1 threshold 3 36 77 100 318 mls qos queue-set output 1 threshold 4 20 50 67 400 mls qos queue-set output 2 threshold 1 149 149 100 149 mls qos queue-set output 2 threshold 2 118 118 100 235 mls qos queue-set output 2 threshold 3 41 68 100 272 mls qos queue-set output 2 threshold 4 42 72 100 242 mls qos queue-set output 1 buffers 10 10 26 54 mls qos queue-set output 2 buffers 16 6 17 61 mls qos ! crypto pki trustpoint HTTPS_SS_CERT_KEYPAIR enrollment selfsigned serial-number revocation-check none rsakeypair HTTPS_SS_CERT_KEYPAIR ! spanning-tree mode pvst spanning-tree extend system-id ! vlan internal allocation policy ascending ! ip ssh time-out 60 ip ssh authentication-retries 2 ! interface FastEthernet0/1 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/2 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/3 description vip5312-3752 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/4 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/5 description vip5330-3757 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/6 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/7 description vip5330-3756 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/8 description vip5312-3759 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/9 description vip5330-3755 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/10 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/11 description vip5312-3758 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/12 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/13 description vip5330-3754 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/14 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/15 description vip5312-3732 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/16 description camCDCNetRm switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/17 description vip5312-3751 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/18 description vip5312-3760 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/19 description vip5312-3750 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/20 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/21 description vip5312-3761 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/22 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/23 description vip5312-3762 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/24 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/25 description vip5312-3763 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/26 switchport mode access switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/27 description vip5312-3764 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/28 description AP.Ware.Out.Corner switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/29 description vip5312-3765 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/30 description AP.Ware.Out.Center switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/31 description vip5312-3766 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/32 description WLC Port 2 (VL06) switchport access vlan 6 switchport mode access spanning-tree portfast ! interface FastEthernet0/33 description WLC Port 3 (VL07) switchport access vlan 7 switchport mode access spanning-tree portfast ! interface FastEthernet0/34 switchport mode access spanning-tree portfast ! interface FastEthernet0/35 description vip5312-3753 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/36 description AP.Mech switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk spanning-tree portfast ! interface FastEthernet0/37 description vip5312-3610 switchport mode access switchport voice vlan 2 switchport port-security aging type inactivity srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 mls qos trust device cisco-phone mls qos trust cos auto qos voip cisco-phone macro description cisco-phone spanning-tree portfast spanning-tree bpduguard enable ! interface FastEthernet0/38 switchport mode access spanning-tree portfast ! interface FastEthernet0/39 description WLC Port 4 switchport mode access spanning-tree portfast ! interface FastEthernet0/40 description WLC Port 1 (VL05) switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk spanning-tree portfast ! interface FastEthernet0/41 description AP.Warehouse02 switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/42 description AP.Warehouse03 switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/43 description AP.Warehouse01 switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/44 description AP.CDC.Dwnstairs switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/45 description AP.CDC.Upstairs switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/46 description AP.CDCGuard switchport trunk encapsulation dot1q switchport trunk native vlan 5 switchport mode trunk switchport voice vlan 2 spanning-tree portfast ! interface FastEthernet0/47 description CDC-3300 switchport access vlan 2 switchport mode access spanning-tree portfast ! interface FastEthernet0/48 spanning-tree portfast ! interface GigabitEthernet0/1 description HDServerSwitch SM- switchport trunk encapsulation dot1q switchport mode trunk srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 queue-set 2 mls qos trust cos auto qos voip trust macro description cisco-switch spanning-tree link-type point-to-point ! interface GigabitEthernet0/2 description BillingVoipSwitch switchport trunk encapsulation dot1q switchport mode trunk srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 queue-set 2 mls qos trust cos auto qos voip trust macro description cisco-switch spanning-tree link-type point-to-point ! interface GigabitEthernet0/3 description CDCDelivSwitch MM Fiber switchport trunk encapsulation dot1q switchport mode trunk ! interface GigabitEthernet0/4 description CDCSwitch MM Fiber switchport trunk encapsulation dot1q switchport mode trunk srr-queue bandwidth share 10 10 60 20 srr-queue bandwidth shape 10 0 0 0 queue-set 2 mls qos trust cos auto qos voip trust macro description cisco-switch spanning-tree link-type point-to-point ! interface Vlan1 ip address 172.16.116.2 255.255.240.0 ! interface Vlan2 ip address 172.16.129.4 255.255.255.0 ! interface Vlan3 ip address 172.16.130.4 255.255.255.0 ! ip classless ip route 0.0.0.0 0.0.0.0 172.16.112.1 ip http server ip http secure-server ! line con 0 line vty 0 4 length 0 transport input ssh line vty 5 15 transport input ssh ! ntp clock-period 36029198 ntp server 172.16.112.6 key 0 prefer ntp server 169.229.70.95 key 0 prefer end
接下来是2960交换机（HDServerSwitch）：
Current configuration : 7496 bytes ! ! Last configuration change at 15:32:04 UTC Mon Apr 7 2014 by admin ! NVRAM config last updated at 15:35:13 UTC Tue Mar 3 2015 ! version 12.2 no service pad service timestamps debug datetime msec service timestamps log datetime msec service password-encryption service sequence-numbers ! hostname HDServerSwitch ! boot-start-marker boot-end-marker ! aaa new-model ! aaa session-id common clock timezone UTC -5 0 ! ip domain-name caymanport.com ip name-server 172.16.112.6 ip name-server 172.16.112.23 ip name-server 172.16.112.9 udld aggressive ! mls qos srr-queue output cos-map queue 1 threshold 3 5 mls qos srr-queue output cos-map queue 2 threshold 3 3 6 7 mls qos srr-queue output cos-map queue 3 threshold 3 2 4 mls qos srr-queue output cos-map queue 4 threshold 2 1 mls qos srr-queue output cos-map queue 4 threshold 3 0 mls qos ! crypto pki trustpoint TP-self-signed-1538847872 enrollment selfsigned subject-name cn=IOS-Self-Signed-Certificate-1538847872 revocation-check none rsakeypair TP-self-signed-1538847872 ! spanning-tree mode rapid-pvst spanning-tree loopguard default spanning-tree extend system-id ! errdisable recovery cause link-flap errdisable recovery interval 60 ! vlan internal allocation policy ascending ! ip ssh time-out 60 ip ssh authentication-retries 2 ! macro global description cisco-global ! interface Port-channel1 description RumPoint LACP Team spanning-tree portfast ! interface FastEthernet0 no ip address ! interface GigabitEthernet0/1 description VsxHD01-4 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/2 description VsxHD02-6 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/3 description VsxHD01-5 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/4 description VsxHD02-0 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/5 description VsxHD01-3 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/6 description VsxHD02-5 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/7 description VsxHD01-2 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/8 description VsxHD02-4 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/9 description RumPoint-1 spanning-tree portfast channel-protocol lacp ! interface GigabitEthernet0/10 description VsxHD02-3 (VL10) switchport access vlan 10 switchport mode access spanning-tree portfast ! interface GigabitEthernet0/11 description RumPoint-2 spanning-tree portfast ! interface GigabitEthernet0/12 description VsxHD02-7 (VL10) switchport access vlan 10 switchport mode access spanning-tree portfast ! interface GigabitEthernet0/13 spanning-tree portfast ! interface GigabitEthernet0/14 description VsxHD02-1 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/15 spanning-tree portfast ! interface GigabitEthernet0/16 description VsxHD02-2 switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/17 spanning-tree portfast ! interface GigabitEthernet0/18 description VsxHD02ILO switchport mode trunk spanning-tree portfast ! interface GigabitEthernet0/19 spanning-tree portfast ! interface GigabitEthernet0/20 spanning-tree portfast ! interface GigabitEthernet0/21 spanning-tree portfast ! interface GigabitEthernet0/22 spanning-tree portfast ! interface GigabitEthernet0/23 spanning-tree portfast ! interface GigabitEthernet0/24 description KVMHD spanning-tree portfast ! interface GigabitEthernet0/25 description CDCVoipSwitch SM-F switchport mode trunk mls qos trust cos macro description cisco-switch spanning-tree link-type point-to-point spanning-tree guard none ! interface GigabitEthernet0/26 description HDSwitch CAT5 switchport mode trunk shutdown mls qos trust cos macro description cisco-switch spanning-tree link-type point-to-point ! interface Vlan1 ip address 172.16.112.57 255.255.240.0 ! interface Vlan10 ip address 172.16.200.57 255.255.255.0 ! ip default-gateway 172.16.112.1 ip http server ip http secure-server ! logging esm config logging history size 500 logging history informational ! line con 0 line vty 0 4 transport input ssh line vty 5 15 transport input ssh ! ntp server 172.16.112.6 prefer ntp server 169.229.70.95 prefer end
你可以在这里看到networking的拓扑结构： http ： //imgur.com/1CvaqUt
Netgear交换机现在连接到CDCSwitch端口30（尽pipe它在一点连接到BillingSwitch）。 这是该端口的configuration：
interface FastEthernet0/30 description CDCParts1Switch switchport trunk encapsulation dot1q switchport mode trunk spanning-tree link-type point-to-point !
CDCVOIPSwitch和HDServerSwitch之间的链接正在closures。
我不是STP的专家，但是我会对此做一个解释。
基于在STP拓扑变化期间发生的情况，短暂的连接性丧失听起来像我预期的行为。
当STP拓扑发生变化时（由于交换机端口转换到阻塞或转发状态或转换状态，由于交换机或上行链路被添加，删除或失败），由于目标MAC地址可用，某些帧可能被“黑色”一条不再存在的path。 直到STP收敛并且MAC地址表到期，这在STP拓扑变化的情况下从300秒的默认值减less到15秒。 由于MAC地址表到期，帧也将通过交换基础设施进行泛滥。
所以再次，你正在经历的听起来像预期的行为。