ISDN 拔入与AAA   Date:2001.6.29

Keywords: ISDN AAA Cisco Secure PPP NAS ACL

一台3620上同时配置了8个口BRI和8个内置MODEM用作拔入。因为对公服务,安全性要求比较高,所以使用一台NT 运行 Cisco Secure 2.4 (ACS) 提供AAA服务(Authentication 认证,Authorization 授权,Accounting记帐)。

PSTN 和AAA的集成没有问题,很容易就实现了。

ISDN 拔号要实现授权不同于PSTN,根据CISCO的文档,必须要用Per-User的AAA设置方法(不能通过Group设置用户)和配置Virtual Profile.

由于没有较好的范例可以借鉴,只能通过观察debug ppp negotiation, debug authentication, debug aaa authorization 等命令的输出来摸索配置方法,所以这个配置至少花掉我24个小时,可谓呕心沥血之作。

本例中,当用户user1通过pstn/isdn拔入时,AAA服务器指示(授权)NAS(拔号访问服务器,即3620)对该用户应用access-list 101.

! 3620 配置 (摘要)

aaa new-model
aaa authentication login default group tacacs+ local
aaa authentication login no_tacacs enable
aaa authentication ppp default group tacacs+
aaa authorization network default group tacacs+
aaa accounting network default start-stop group tacacs+
enable secret 5 $1$FlnA$pGA5cmuIqOOJwFT0iLWdq0
!
username localuser password 0 _password
ip subnet-zero
!
!
no ip finger
no ip domain-lookup
!
virtual-profile virtual-template 1
virtual-profile aaa
isdn switch-type basic-net3
!
!
!
interface FastEthernet0/0
 ip address 10.1.10.33 255.255.255.0
 duplex auto
 speed auto
!
interface BRI1/0
 ip unnumbered FastEthernet0/0
 encapsulation ppp
 no ip route-cache
 no ip mroute-cache
 no keepalive
 dialer-group 1
 isdn switch-type basic-net3
 peer default ip address pool ip_pool
 no fair-queue
 ppp authentication chap pap
 ppp multilink
!
interface BRI1/1
 ip unnumbered FastEthernet0/0
 encapsulation ppp
 no ip route-cache
 no ip mroute-cache
 no keepalive
 dialer-group 1
 isdn switch-type basic-net3
 peer default ip address pool ip_pool
 no fair-queue
 ppp authentication chap pap
 ppp multilink
!
...
interface Virtual-Template1
 ip unnumbered FastEthernet0/0
 peer default ip address pool ip_pool
 ppp authentication chap pap
 ppp multilink
 ppp timeout idle 300
!
interface Group-Async0
 ip unnumbered FastEthernet0/0
 encapsulation ppp
 ip tcp header-compression passive
 async dynamic routing
 async mode interactive
 peer default ip address pool ip_pool
 ppp authentication chap pap
 group-range 65 80
!

ip local pool ip_pool 10.1.10.1 10.1.10.32
ip classless
ip route 0.0.0.0 0.0.0.0 10.1.10.34
no ip http server
!
access-list 101 deny   icmp any host 10.1.11.1 log
access-list 101 permit ip any any
dialer-list 1 protocol ip permit
tacacs-server host 10.1.10.36 single-connection
tacacs-server key _key

!
line con 0
 login authentication no_tacacs
 transport input none
line 65 80
 autoselect during-login
 autoselect ppp
 modem InOut
 modem autoconfigure discovery
 transport input all
 stopbits 1
 flowcontrol hardware

! ACS 配置 (用户):
设定密码,指定IP分配方法;选中PPP IP, INACL设为101,选中MULTILINK,LCP. 


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