Cisco 1921上VLAN之间的路由选择

Question

我已经为正在安装的VoIP手机安装了一个新的VLAN。我想将他们的流量分割到10.20.77.0/24号子网。我向DHCP服务器添加了一个IP地址10.20.77.11，以帮助为此VLAN提供DHCP通信量。当我将笔记本电脑连接到此VLAN上的开关端口时，它不会获取IP地址，我也无法在DHCP服务器的地址10.20.77.11上进行平分。我认为我有一个ACL或NAT问题，但我不了解思科足够的故障排除在我自己。

路由器在运行Config

Current configuration : 6198 bytes
!
! Last configuration change at 10:09:23 gmt Wed Nov 1 2017 by admin
!
version 15.6
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname EASI-FW1
!
boot-start-marker
boot-end-marker
!
!
logging buffered 51200 warnings
!
no aaa new-model
ethernet lmi ce
clock timezone gmt -8 0
!
!
!
!
!
!
!
!
!
!
!
!
ip domain name contoso.local
ip cef
no ipv6 cef
!
multilink bundle-name authenticated
!
!
license udi pid CISCO1921/K9 sn 
!
!
!
redundancy
!
!
!
!
lldp run
!
!
class-map match-any Voice
 match protocol sip
 match protocol rtp audio
class-map match-any QoS-Bulk
 match protocol secure-nntp
 match protocol smtp
 match protocol tftp
 match protocol ftp
class-map match-any QoS-Management
 match protocol snmp
 match protocol dns
 match protocol secure-imap
class-map match-any QoS-Inter-Video
 match protocol rtp video
class-map match-any QoS-Voice-Control
 match access-group name Voice-Control
!
policy-map QOS
 class Voice
  priority percent 25
  set dscp ef
 class QoS-Inter-Video
  bandwidth remaining percent 10
  set dscp af41
 class QoS-Bulk
  bandwidth remaining percent 5
  random-detect dscp-based
  set dscp af11
 class QoS-Management
  bandwidth remaining percent 1
  set dscp cs2
 class QoS-Voice-Control
  priority percent 5
  set dscp ef
 class class-default
  fair-queue
!
!
!
!
!
!
!
!
!
!
!
interface Embedded-Service-Engine0/0
 no ip address
 shutdown
!
interface GigabitEthernet0/0
 no ip address
 duplex auto
 speed auto
!
interface GigabitEthernet0/0.1
 description LAN
 encapsulation dot1Q 1 native
 ip address 10.20.75.1 255.255.255.0
 ip access-group Local in
 ip access-group Local out
 ip flow ingress
 ip flow egress
 ip nat inside
 ip virtual-reassembly in
 ip policy route-map LAN
!
interface GigabitEthernet0/0.76
 description SteelNet76
 encapsulation dot1Q 76
 ip address 10.20.76.1 255.255.255.0
 ip access-group Local in
 ip access-group Local out
 ip flow ingress
 ip flow egress
 ip nat inside
 ip virtual-reassembly in
 ip policy route-map WLAN76
!
interface GigabitEthernet0/0.200
 description Voice
 encapsulation dot1Q 200
 ip address 10.20.77.1 255.255.255.0
 ip access-group Local in
 ip access-group Local out
 ip flow ingress
 ip flow egress
 ip nat inside
 ip virtual-reassembly in
 ip policy route-map SIP200
!
interface GigabitEthernet0/1
 description TelusWAN
 ip address dhcp
 ip nat outside
 ip virtual-reassembly in
 duplex auto
 speed auto
!
ip forward-protocol nd
!
no ip http server
ip http access-class 23
ip http authentication local
no ip http secure-server
ip http timeout-policy idle 60 life 86400 requests 10000
!
ip nat inside source static tcp 10.20.75.11 443 interface GigabitEthernet0/1 443
ip nat inside source static tcp 10.20.75.11 987 interface GigabitEthernet0/1 987
ip nat inside source static tcp 10.20.75.11 1723 interface GigabitEthernet0/1 1723
ip nat inside source route-map LAN interface GigabitEthernet0/1 overload
ip nat inside source route-map SIP200 interface GigabitEthernet0/1 overload
ip nat inside source route-map WLAN76 interface GigabitEthernet0/1 overload
ip route 0.0.0.0 0.0.0.0 GigabitEthernet0/1 track 1
ip ssh time-out 60
ip ssh authentication-retries 2
ip ssh version 2
!
ip access-list extended LAN
 permit ip 10.20.75.0 0.0.0.255 any
 deny   ip any any
ip access-list extended SIP200
 permit ip 10.20.77.0 0.0.0.255 any
 deny   ip any any
ip access-list extended WLAN76
 permit ip 10.20.76.0 0.0.0.255 any
 deny   ip any any
!
!
route-map WLAN76 permit 20
 match ip address WLAN76
 set interface GigabitEthernet0/1
 set default interface GigabitEthernet0/1
!
route-map LAN permit 10
 match ip address LAN
 set interface GigabitEthernet0/1
 set default interface GigabitEthernet0/1
!
route-map SIP200 permit 30
 match ip address SIP200
 set interface GigabitEthernet0/1
 set default interface GigabitEthernet0/1
!
!
access-list 23 permit XXX.XX.XXX.196
access-list 23 permit 10.20.75.0 0.0.0.255
access-list 24 permit 10.20.77.0 0.0.0.255
access-list 120 permit ip 0.0.0.11 255.255.255.0 any
!
control-plane
!
!
!
line con 0
 login local
line aux 0
line 2
 no activation-character
 no exec
 transport preferred none
 transport output pad telnet rlogin lapb-ta mop udptn v120 ssh
 stopbits 1
line vty 0 4
 access-class 23 in
 privilege level 15
 login local
 transport input ssh
line vty 5 15
 access-class 23 in
 privilege level 15
 login local
 transport input telnet ssh
!
scheduler allocate 20000 1000
!
end

EASI-FW1#

路线图应该指定Gi0/1的子接口吗？

Answer 1

听起来您的DHCP服务器只是在同一个VLAN上使用一个辅助地址作为其主地址。那是行不通的。您可以简单地为DHCP中继添加一个辅助地址。例如：

interface GigabitEthernet0/0.200
 description Voice
 encapsulation dot1Q 200
 ip address 10.20.77.1 255.255.255.0
 ip helper-address 10.20.75.11
!

这将在10.20.77.0/24网络上向10.20.75.11的DHCP服务器发送任何DHCP请求，并将来自服务器的任何响应发送回原始网络。如果在DHCP服务器上配置了正确的DHCP范围，那么一切都应该正常工作。

这样做就不需要DHCP服务器在10.20.77.0/24网络上有一个地址，所以您可以删除二级寻址。

如果您想要DHCP服务器上的辅助地址，那么您需要在交换机和服务器上设置一个主干接口。