Question

我有一台Cisco 2600路由器有两个nic卡fa0 / 0和fa0 / 1，我的路由器配置如下：问题是我的笔记本电脑没有从我在Windows上运行的DHCP服务器获取IP地址Server 2003机器。如果我为我的笔记本电脑分配一个静态IP地址，那么它可以正常工作。笔记本电脑连接到Cisco 2900交换机到端口fa0 / 2，配置如下。我想我在这里遗漏了一些小问题，但是无法理解。

    Building configuration...

Current configuration : 1738 bytes
!
version 12.3
no parser cache
service timestamps debug datetime msec
service timestamps log datetime msec
service password-encryption
!
hostname Router
!
boot-start-marker
boot system flash:c2600-is4-mz.123-26.bin
boot-end-marker
!
no logging buffered
no logging console
no logging monitor
logging cns-events debugging
enable secret 5 $1$Ccel$fXywUTjW4JDN1I/6r5l2M1
!
no aaa new-model
ip subnet-zero
ip cef
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
!
interface FastEthernet0/0
 description Connection to Bell Modem
 ip address 192.168.0.252 255.255.255.0
 ip nat outside
 duplex auto
 speed auto
!
interface Serial0/0
 no ip address
!
interface FastEthernet0/1
 description Connection to the Cisco LAB
 ip address 192.168.1.254 255.255.255.0
 ip helper-address 192.168.0.10
 ip nat inside
 duplex auto
 speed auto
 no cdp enable
!
ip nat inside source list 101 interface FastEthernet0/0 overload
ip nat inside source list ACL-NAT interface FastEthernet0/0 overload
no ip http server
ip classless
ip route 0.0.0.0 0.0.0.0 192.168.0.254
!
!
!
ip access-list extended ACL-NAT
 permit tcp any any
 permit ip any any
logging trap debugging
logging server-arp
!
!
!
dial-peer cor custom
!
!
!
banner motd ^C
====================================================================================
= Welcome to paulaga.com domain, all your activity is being monitored and logged   =
= all un-authorized access to this device is prihibited and will be used against   =
= you in the court of law. Please use this device with permission accordingly      =
====================================================================================
!
^C
!
line con 0
 password 7 104D000A0618
 login
line aux 0
line vty 0 4
 no login
line vty 5 15
 no login
!
!
end

Cisco 2900交换机配置

Building configuration...

Current configuration:
!
version 12.0
no service pad
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname Switch
!
enable secret 5 $1$sryH$prFN3pwacSY11N8TnMyxD0
!
!
!
!
!
!
ip subnet-zero
ip name-server 192.168.0.10
ip dhcp-server 192.168.0.10
!
!
controller LongReachEthernet 0
!
controller LongReachEthernet 1
!
controller LongReachEthernet 2
!
controller LongReachEthernet 3
!
controller LongReachEthernet 4
!
controller LongReachEthernet 5
!
controller LongReachEthernet 6
!
controller LongReachEthernet 7
!
controller LongReachEthernet 8
!
controller LongReachEthernet 9
!
controller LongReachEthernet 10
!
controller LongReachEthernet 11
!
controller LongReachEthernet 12
!
controller LongReachEthernet 13
!
controller LongReachEthernet 14
!
controller LongReachEthernet 15
!
controller LongReachEthernet 16
!
controller LongReachEthernet 17
!
controller LongReachEthernet 18
!
controller LongReachEthernet 19
!
controller LongReachEthernet 20
!
controller LongReachEthernet 21
!
controller LongReachEthernet 22
!
controller LongReachEthernet 23
!
!
interface FastEthernet0/1
!
interface FastEthernet0/2
!
interface FastEthernet0/3
!
interface FastEthernet0/4
!
interface FastEthernet0/5
!
interface FastEthernet0/6
!
interface FastEthernet0/7
!
interface FastEthernet0/8
!
interface FastEthernet0/9
!
interface FastEthernet0/10
!
interface FastEthernet0/11
!
interface FastEthernet0/12
!
interface FastEthernet0/13
!
interface FastEthernet0/14
!
interface FastEthernet0/15
!
interface FastEthernet0/16
!
interface FastEthernet0/17
!
interface FastEthernet0/18
!
interface FastEthernet0/19
!
interface FastEthernet0/20
!
interface FastEthernet0/21
!
interface FastEthernet0/22
!
interface FastEthernet0/23
!
interface FastEthernet0/24
!
interface VLAN1
 ip address 192.168.1.253 255.255.255.0
 no ip directed-broadcast
 no ip route-cache
!
ip default-gateway 192.168.1.254
snmp-server engineID local 00000009020000309479B000
snmp-server community private RW
snmp-server community public RO
!
line con 0
 transport input none
 stopbits 1
line vty 0 4
 password cisco
 login
line vty 5 15
 password cisco
 login
!
end

Answer 1

实际上，服务器似乎连接的网络地址错误。基本上你可能会倒退一些事情。 VLAN 1 - 192.168.1.0/24 服务器：192.168.0.10（假设服务VLAN 1地址）

使用正确的默认网关192.168.1.254将IP更改为192.168.1.0/24中的地址。

除非服务器F0 / 0和调制解调器连接到与192.168.1.0/24相同的VLAN（VLAN1）中的交换机。这就是你的持续路线有效的原因。

我实验室设置的方式如下：

router
  -- F0/0 - WAN or a VLAN other than VLAN 1 - Network 192.168.0.0/24
  -- F0/1 - LAN VLAN 1 or any other unassigned VLAN - Network 192.168.1.0/24
switch
  -- F0/1 - VLAN1 - ROUTER F0/1
  -- F0/2 - VLAN1 - DHCP  Server
  -- F0/3 - VLANXX - ROUTER F0/0
  -- F0/4 - VLANXX - CABLE MODEM

BTW你的ACL 101应用程序没有做任何未配置的事情

Answer 2

最新答案，但问题出在OP在两个接口之间使用NAT。来自DHCP客户端的数据包被整理到DHCP服务器。

Answer 3

我找到了解决方案，在我安装了DHCP服务器的Windows Server 2003上，我不得不添加静态路由来告诉服务器如何到达192.168.1.0网络。看，源自Cisco路由器的数据包到达我的Windows DHCP服务器没有问题，但是回复数据包不知道如何到达192.168.1.0网络...我添加了以下静态路由并且它完美地运行：

route ADD 192.168.1.0 MASK 255.255.255.0 192.168.0.252 metric 1

Answer 4

确保您使路由持久，否则在重新启动服务器时将删除该路由。

Cisco 2600 DHCP无法中继

4 个答案: