网络工程 - 无法让 DHCP 在生成树中工作 - 吾爱随笔录

无法让 DHCP 在生成树中工作

网络工程思科 VLAN dhcp 生成树数据包追踪器

2021-08-03 15:11:31

我不完全确定我做错了什么。我使用我用作默认路由器的 IP 地址从主路由器配置了 VLAN 间路由，我也在主路由器中设置了 DHCP 池。我设置了生成树 VLAN，甚至为生成树中的所有交换机添加了交换机端口本机 VLAN。我在第一台 PC 上添加了一个交换机端口访问权限来测试它，但它不起作用，我需要一些帮助。这是我的数据包跟踪器文件：https : //drive.google.com/file/d/1g6yE9gmgRWFj6gWLt-FYNAylYLyYyqPV/view? usp =sharing

这是网络的地图。没有一台 PC 可以获得 DHCP。我也没有连接无线 AP，因为我想首先确保 PC 可以获得 DHCP。主路由器和 2 个主交换机在 MDF 中，其他 6 个功能在 IDF 中。

路由器：

Building configuration...

Current configuration : 3910 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
service password-encryption
!
hostname Router
!
!
!
enable password 7 0822404F1A0A
!
!
ip dhcp excluded-address 192.168.8.1 192.168.8.10
ip dhcp excluded-address 192.168.9.1 192.168.9.10
ip dhcp excluded-address 192.168.9.129 192.168.9.138
ip dhcp excluded-address 192.168.10.1 192.168.10.10
ip dhcp excluded-address 192.168.10.65 192.168.10.74
ip dhcp excluded-address 192.168.10.81 192.168.10.90
ip dhcp excluded-address 192.168.10.97 192.168.10.106
ip dhcp excluded-address 192.168.10.113 192.168.10.116
ip dhcp excluded-address 192.168.10.121 192.168.10.122
ip dhcp excluded-address 192.168.10.124 192.168.10.125
!
ip dhcp pool Students-ELEMENTARY-POOL
 network 192.168.8.0 255.255.255.0
 default-router 192.168.8.1
ip dhcp pool Wireless-ELEMENTARY-POOL
 network 192.168.9.0 255.255.255.128
 default-router 192.168.9.1
ip dhcp pool VoIP-ELEMENTARY-POOL
 network 192.168.9.128 255.255.255.128
 default-router 192.168.9.129
ip dhcp pool Faculty-ELEMENTARY-POOL
 network 192.168.10.0 255.255.255.192
 default-router 192.168.10.1
ip dhcp pool IP-Camera-ELEMENTARY-Pool
 network 192.168.10.64 255.255.255.240
 default-router 192.168.10.65
ip dhcp pool Admin-ELEMENTARY-POOL
 network 192.168.10.80 255.255.255.240
 default-router 192.168.10.81
ip dhcp pool Printer-ELEMENTARY-POOL
 network 192.168.10.96 255.255.255.240
 default-router 192.168.10.97
ip dhcp pool Staff-ELEMENTARY-POOL
 network 192.168.10.112 255.255.255.248
 default-router 192.168.10.113
ip dhcp pool Management-ELEMENTARY-POOL
 network 192.168.10.120 255.255.255.252
 default-router 192.168.10.121
ip dhcp pool Native-ELEMENTARY-POOL
 network 192.168.10.124 255.255.255.252
 default-router 192.168.10.125
!
!
!
no ip cef
no ipv6 cef
!
!
!
!
license udi pid CISCO2901/K9 sn FTX1524EIIO
!
!
!
!
!
!
!
!
!
no ip domain-lookup
!
!
spanning-tree mode pvst
!
!
!
!
!
!
interface GigabitEthernet0/0
 description MCE_MDF_Router to MCE_MDF_CoreSW1
 no ip address
 duplex auto
 speed auto
!
interface GigabitEthernet0/0.10
 encapsulation dot1Q 10
 ip address 192.168.10.81 255.255.255.240
!
interface GigabitEthernet0/0.20
 encapsulation dot1Q 20
 ip address 192.168.8.1 255.255.255.0
!
interface GigabitEthernet0/0.30
 encapsulation dot1Q 30
 ip address 192.168.10.113 255.255.255.248
!
interface GigabitEthernet0/0.40
 encapsulation dot1Q 40
 ip address 192.168.10.1 255.255.255.192
!
interface GigabitEthernet0/0.50
 encapsulation dot1Q 50
 ip address 192.168.10.97 255.255.255.240
!
interface GigabitEthernet0/0.60
 encapsulation dot1Q 60
 ip address 192.168.9.1 255.255.255.128
!
interface GigabitEthernet0/0.70
 encapsulation dot1Q 70
 ip address 192.168.9.129 255.255.255.128
!
interface GigabitEthernet0/0.80
 encapsulation dot1Q 80
 ip address 192.168.10.121 255.255.255.252
!
interface GigabitEthernet0/0.88
 encapsulation dot1Q 88
 ip address 192.168.10.65 255.255.255.240
!
interface GigabitEthernet0/0.99
 encapsulation dot1Q 99 native
 ip address 192.168.10.125 255.255.255.252
!
interface GigabitEthernet0/1
 no ip address
 duplex auto
 speed auto
!
interface GigabitEthernet0/1.10
 encapsulation dot1Q 10
 no ip address
!
interface GigabitEthernet0/1.20
 encapsulation dot1Q 20
 no ip address
!
interface GigabitEthernet0/1.99
 encapsulation dot1Q 99 native
 no ip address
!
interface Serial0/0/0
 no ip address
 clock rate 2000000
 shutdown
!
interface Serial0/0/1
 no ip address
 clock rate 2000000
 shutdown
!
interface Vlan1
 no ip address
 shutdown
!
ip classless
!
ip flow-export version 9
!
!
!
no cdp run
!
banner motd ^CNo Unauthorized Access^C
!
!
!
!
line con 0
 exec-timeout 15 0
 password 7 0822455D0A16
 logging synchronous
 login
!
line aux 0
!
line vty 0 4
 exec-timeout 15 0
 password 7 0822455D0A16
 logging synchronous
 login
line vty 5 15
 exec-timeout 15 0
 password 7 0822455D0A16
 logging synchronous
 login
!
!
!
end

MDF 交换机核心 1：

Building configuration...

Current configuration : 3369 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Switch
!
!
!
!
!
spanning-tree mode pvst
spanning-tree extend system-id
spanning-tree vlan 10,20,30,40,50,60 priority 24576
spanning-tree vlan 70,80,88,99 priority 28672
!
interface FastEthernet0/1
 description MCE_MDF_CoreSw1 to MCE_IDF_Switch1_STUDENT
 switchport trunk native vlan 99
 switchport mode trunk
 switchport nonegotiate
!
interface FastEthernet0/2
 description MCE_MDF_CoreSw1 to MCE_IDF_Switch2
 switchport access vlan 80
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/3
 description MCE_MDF_CoreSw1 to MCE_IDF_Switch3
 switchport access vlan 88
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/4
 description MCE_MDF_CoreSw1 to MCE_IDF_Switch4
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/5
 description MCE_MDF_CoreSw1 to MCE_IDF_Switch5
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/6
 description MCE_MDF_CoreSw1 to MCE_IDF_Switch6
 switchport trunk native vlan 99
 switchport trunk allowed vlan 10
 switchport mode trunk
!
interface FastEthernet0/7
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/8
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/9
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/10
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/11
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/12
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/13
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/14
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/15
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/16
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/17
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/18
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/19
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/20
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/21
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/22
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/23
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/24
 switchport access vlan 60
 switchport trunk native vlan 99
 switchport mode trunk
 switchport port-security maximum 60
 switchport port-security violation restrict 
!
interface GigabitEthernet0/1
 description MCE_MDF_CoreSw1 to MCE_MDF_Router
 switchport trunk native vlan 99
 switchport mode trunk
!
interface GigabitEthernet0/2
 description MCE_MDF_CoreSw1 to MCE_MDF_CoreSw2
 switchport trunk native vlan 99
 switchport mode trunk
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan80
 mac-address 0002.17d4.6101
 ip address 192.168.10.122 255.255.255.248
!
ip default-gateway 192.168.10.125
!
!
!
!
line con 0
!
line vty 0 4
 login
line vty 5 15
 login
!
!
!
end

MDF 交换机核心 2：

Building configuration...

Current configuration : 3056 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Switch
!
!
!
!
!
no spanning-tree vlan 10,60
spanning-tree mode pvst
spanning-tree extend system-id
spanning-tree vlan 70,80,88,99 priority 24576
spanning-tree vlan 10,20,30,40,50,60 priority 28672
!
interface FastEthernet0/1
 switchport access vlan 10
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/2
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/3
 switchport access vlan 30
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/4
 switchport access vlan 40
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/5
 switchport access vlan 50
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/6
 switchport access vlan 60
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/7
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/8
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/9
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/10
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/11
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/12
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/13
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/14
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/15
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/16
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/17
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/18
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/19
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/20
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/21
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/22
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/23
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/24
 switchport access vlan 60
 switchport trunk native vlan 99
 switchport mode trunk
 switchport port-security maximum 60
 switchport port-security violation restrict 
!
interface GigabitEthernet0/1
 switchport trunk native vlan 99
 switchport mode trunk
!
interface GigabitEthernet0/2
 switchport trunk native vlan 99
 switchport mode trunk
!
interface Vlan1
 no ip address
 shutdown
!
interface Vlan80
 mac-address 0007.ecb7.0001
 ip address 192.168.10.123 255.255.255.248
!
ip default-gateway 192.168.10.125
!
!
!
!
line con 0
!
line vty 0 4
 login
line vty 5 15
 login
!
!
!
end

IDF 开关：

Building configuration...

Current configuration : 3363 bytes
!
version 12.2
no service timestamps log datetime msec
no service timestamps debug datetime msec
no service password-encryption
!
hostname Switch
!
!
!
!
!
spanning-tree mode pvst
spanning-tree extend system-id
!
interface FastEthernet0/1
 description MCE_IDF1_Switch1_STUDENT to PC0
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/2
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/3
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/4
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/5
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/6
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/7
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/8
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/9
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/10
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/11
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/12
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/13
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/14
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/15
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/16
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/17
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/18
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/19
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/20
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/21
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/22
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/23
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface FastEthernet0/24
 switchport access vlan 20
 switchport trunk native vlan 99
 switchport mode access
!
interface GigabitEthernet0/1
 description MCE_IDF1_Switch1_STUDENT to MCE_MDF_CoreSw1
 switchport trunk native vlan 99
 switchport mode trunk
!
interface GigabitEthernet0/2
 description MCE_IDF1_Switch1_STUDENT to MCE_MDF_CoreSw2
 switchport trunk native vlan 99
 switchport mode trunk
!
interface Vlan1
 no ip address
 shutdown
!
!
!
!
line con 0
!
line vty 0 4
 login
line vty 5 15
 login
!
!
!
end

来自路由器的 CDP：

Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID    Local Intrfce   Holdtme    Capability   Platform    Port ID

来自核心交换机 1 的 CDP：

Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID    Local Intrfce   Holdtme    Capability   Platform    Port ID

来自核心交换机 2 的 CDP：

Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID    Local Intrfce   Holdtme    Capability   Platform    Port ID
Switch       Gig 0/2          141            S       2960        Gig 0/2

来自 IDF Switch 1 的 CDP（学生）：

Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID    Local Intrfce   Holdtme    Capability   Platform    Port ID
Switch       Gig 0/2          177            S       2960        Fas 0/1

MDF 核心交换机 1 上 VLAN 10 的生成树：

VLAN0010
  Spanning tree enabled protocol ieee
  Root ID    Priority    24586
             Address     0002.17D4.61B6
             This bridge is the root
             Hello Time  2 sec  Max Age 20 sec  Forward Delay 15 sec

  Bridge ID  Priority    24586  (priority 24576 sys-id-ext 10)
             Address     0002.17D4.61B6
             Hello Time  2 sec  Max Age 20 sec  Forward Delay 15 sec
             Aging Time  20

Interface        Role Sts Cost      Prio.Nbr Type
---------------- ---- --- --------- -------- --------------------------------
Fa0/2            Desg FWD 19        128.2    P2p
Fa0/3            Desg FWD 19        128.3    P2p
Fa0/4            Desg FWD 19        128.4    P2p
Fa0/1            Desg FWD 19        128.1    P2p
Fa0/5            Desg FWD 19        128.5    P2p
Fa0/6            Desg FWD 19        128.6    P2p
Gi0/2            Desg FWD 4         128.26   P2p
Gi0/1            Desg FWD 4         128.25   P2p

2个回答

我无法使用您的数据包跟踪器文件，因为它与我的 7.0 版本不兼容。

您的大部分配置看起来都很好（除了no spanning-tree vlan 10,60MDF_Core_2 和switchport trunk native vlan 99终端设备的每个访问端口。您应该删除它们），我可以将它们应用于以下情况，所有 PC 都可以从路由器获取 IP 地址。

配置：

在路由器上：

!
ip dhcp excluded-address 192.168.8.1 192.168.8.10
ip dhcp excluded-address 192.168.10.113 192.168.10.116
ip dhcp excluded-address 192.168.10.65 192.168.10.74
!
ip dhcp pool Students-ELEMENTARY-POOL
 network 192.168.8.0 255.255.255.0
 default-router 192.168.8.1
ip dhcp pool Staff-ELEMENTARY-POOL
 network 192.168.10.112 255.255.255.248
 default-router 192.168.10.113
ip dhcp pool IP-Camera-ELEMENTARY-Pool
 network 192.168.10.64 255.255.255.240
 default-router 192.168.10.65
!
interface GigabitEthernet0/0
 description MDF_Core_1 (g0/1)
 no ip address
 duplex auto
 speed auto
!
interface GigabitEthernet0/0.10
 encapsulation dot1Q 10
 ip address 192.168.10.81 255.255.255.240
!
interface GigabitEthernet0/0.20
 encapsulation dot1Q 20
 ip address 192.168.8.1 255.255.255.0
!
interface GigabitEthernet0/0.30
 encapsulation dot1Q 30
 ip address 192.168.10.113 255.255.255.248
!
interface GigabitEthernet0/0.40
 encapsulation dot1Q 40
 ip address 192.168.10.1 255.255.255.192
!
interface GigabitEthernet0/0.50
 encapsulation dot1Q 50
 ip address 192.168.10.97 255.255.255.240
!
interface GigabitEthernet0/0.60
 encapsulation dot1Q 60
 ip address 192.168.9.1 255.255.255.128
!
interface GigabitEthernet0/0.70
 encapsulation dot1Q 70
 ip address 192.168.9.129 255.255.255.128
!
interface GigabitEthernet0/0.80
 encapsulation dot1Q 80
 ip address 192.168.10.121 255.255.255.252
!
interface GigabitEthernet0/0.88
 encapsulation dot1Q 88
 ip address 192.168.10.65 255.255.255.240
!
interface GigabitEthernet0/0.99
 encapsulation dot1Q 99 native
 ip address 192.168.10.125 255.255.255.252
!

在 MDF_Core_1 上

!
hostname MDF_Core_1
!
spanning-tree mode pvst
spanning-tree vlan 10,20,30,40,50,60 priority 24576
spanning-tree vlan 70,80,88,99 priority 28672
!
interface FastEthernet0/1
 description IDF_Switch_1 (f0/1)
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/2
 description PC_1
 switchport access vlan 20
 switchport mode access
!
interface GigabitEthernet0/1
 description Router (g0/0)
 switchport trunk native vlan 99
 switchport mode trunk
!
interface GigabitEthernet0/2
 description MDF_Core_2 (g0/2)
 switchport trunk native vlan 99
 switchport mode trunk
!

在 MDF_Core_2 上：

!
hostname MDF_Core_2
!
spanning-tree mode pvst
spanning-tree vlan 70,80,88,99 priority 24576
spanning-tree vlan 10,20,30,40,50,60 priority 28672
!
interface FastEthernet0/1
 description IDF_Switch_1 (f0/2)
 switchport trunk native vlan 99
 switchport mode trunk
!
interface FastEthernet0/2
 description PC_3
 switchport access vlan 88
 switchport mode access
!
interface GigabitEthernet0/2
 description MDF_Core_1 (g0/2)
 switchport trunk native vlan 99
 switchport mode trunk
!

在 IDF_Switch_1 上

!
hostname IDF_Switch_1
!
spanning-tree mode pvst
!
interface FastEthernet0/1
 description MDF_Core_1 (f0/1)
 switchport trunk native vlan 99
 switchport mode trunk
 switchport nonegotiate
!
interface FastEthernet0/2
 description MDF_Core_2 (f0/1)
 switchport trunk native vlan 99
 switchport mode trunk
 switchport nonegotiate
!
interface FastEthernet0/3
 description PC_0
 switchport access vlan 20
 switchport mode access
!
interface FastEthernet0/4
 description PC_2
 switchport access vlan 30
 switchport mode access
!
interface FastEthernet0/5
 description PC_4
 switchport access vlan 88
 switchport mode access
!

显示 CDP 邻居：

起初，路由器可以看到交换机 MDF_Core_1，但后来就看不到了。我认为这是数据包跟踪器应用程序的问题。其余设备正常。

在路由器上：

Router#show cdp ne
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID    Local Intrfce   Holdtme    Capability   Platform    Port ID
Router#

在 MDF_Core_1 上：

MDF_Core_1#show cdp neighbors 
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID    Local Intrfce   Holdtme    Capability   Platform    Port ID
MDF_Core_2   Gig 0/2          158            S       2960        Gig 0/2
IDF_Switch_1 
             Fas 0/1          138            S       2960        Fas 0/1
Router       Gig 0/1          151            R       C2900       Gig 0/0
Router       Gig 0/1          151            R       C2900       Gig 0/0.10
Router       Gig 0/1          151            R       C2900       Gig 0/0.20
Router       Gig 0/1          151            R       C2900       Gig 0/0.30
Router       Gig 0/1          151            R       C2900       Gig 0/0.40
Router       Gig 0/1          151            R       C2900       Gig 0/0.50
Router       Gig 0/1          151            R       C2900       Gig 0/0.60
Router       Gig 0/1          151            R       C2900       Gig 0/0.70
Router       Gig 0/1          151            R       C2900       Gig 0/0.80
Router       Gig 0/1          151            R       C2900       Gig 0/0.88
Router       Gig 0/1          151            R       C2900       Gig 0/0.99
MDF_Core_1#

在 MDF_Core_2 上：

MDF_Core_2#show cdp ne
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID    Local Intrfce   Holdtme    Capability   Platform    Port ID
MDF_Core_1   Gig 0/2          120            S       2960        Gig 0/2
IDF_Switch_1 
             Fas 0/1          167            S       2960        Fas 0/2
MDF_Core_2#

在 IDF_Switch_1 上：

IDF_Switch_1#show cdp ne
Capability Codes: R - Router, T - Trans Bridge, B - Source Route Bridge
                  S - Switch, H - Host, I - IGMP, r - Repeater, P - Phone
Device ID    Local Intrfce   Holdtme    Capability   Platform    Port ID
MDF_Core_2   Fas 0/2          154            S       2960        Fas 0/1
MDF_Core_1   Fas 0/1          148            S       2960        Fas 0/1
IDF_Switch_1#

所有五台 PC 都收到了来自路由器的 IP 地址：

Router#show ip dhcp binding 
IP address       Client-ID/              Lease expiration        Type
                 Hardware address
192.168.8.12     00D0.D349.4C59           --                     Automatic
192.168.8.13     0001.9659.EA40           --                     Automatic
192.168.10.117   0060.70DD.5B08           --                     Automatic
192.168.10.75    0001.6445.404A           --                     Automatic
192.168.10.76    0001.C945.7A23           --                     Automatic
Router#

我建议您在数据包跟踪器中建立另一个具有相同拓扑结构的实验室，并确保：

连接（交换机到交换机和 MDF_Core_1 到路由器）是正确的（使用show cdp neighbors）。
所有交换机上的所有 Vlan 均已正确配置（使用show vlans）
删除switchport trunk native vlan 99在接入端口no spanning-tree vlan 10,60上MDF_Core_2
将不同 VLAN 中不同网络层（MDF 和 IDF 交换机）的 PC 连接起来，看看是否可以找到那里的 IP 地址。这将帮助您缩小问题的范围。
最后但并非最不重要的一点是，在您的中继端口上，switchport trunk allowed vlan 10,20,30,40,50,60,70,80,88,99仅用于中继您在网络中的 vlan。

我希望它有帮助，您可以找到问题所在。

您确定第 1 层一切正常吗？我将从那里开始，如果路由器和第一个核心交换机之间没有禁用 cdp，那么你就会遇到 l1 问题。

检查端口计数器，尝试其他电缆 - 即使这表明它已启动。路由器和交换机之间的电缆长度是多少？检查arp是否路由器从他的核心交换机面向端口学习任何东西，同时检查交换机端的mac地址表是否有面向路由器的端口。如果它是空的，你肯定有 L1 问题。

要在此配置中获取 DHCP 服务器，您需要确保拥有从终端设备到路由器的完整有效 L2 路径。

否则你可以使用 ip helper。

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