我之前没有从头开始配置过 Cisco，但我正在尝试熟悉它。我之前只做过一些调整。
也就是说，我正在尝试诊断使用我的 Cisco 2801 和 HWIC-1ADSL 进行 PPPoE 连接时出现的问题。
PPPoE 身份验证顺利通过，我甚至获得了外部接口的 IP，但我的 ISP 提供的默认路由似乎已提供，但尚未安装。
以下是一些调试输出：
*May 29 05:06:04.950: Vi1 PPP DISC: Authentication configuration changed
*May 29 05:06:04.950: PPP: NET STOP send to AAA.
*May 29 05:06:04.950: Vi1 IPCP: Event[DOWN] State[Open to Starting]
*May 29 05:06:04.950: Vi1 IPCP: Event[CLOSE] State[Starting to Initial]
*May 29 05:06:04.954: Vi1 LCP: Event[DOWN] State[Open to Starting]
*May 29 05:06:04.954: Vi1 PPP: Send Message[Renegotiate]
*May 29 05:06:04.954: Vi1 PPP: Phase is DOWN
*May 29 05:06:04.954: Di0 Deleted neighbor route from AVL tree: topoid 0, address XX.YY.225.104
*May 29 05:06:04.954: Di0 IPCP: Remove route to XX.YY.225.104
*May 29 05:06:04.958: Vi1 PPP: Received Renegotiate from PPP
*May 29 05:06:04.958: Vi1 PPP: ppp_sip_switching_cleanup
*May 29 05:06:04.958: Vi1 PPP: Change SIP state from Init to Down
*May 29 05:06:04.958: Vi1 PPP: Change SIP state from Down to SSS Setup
*May 29 05:06:04.958: Vi1 PPP: old[Down] event[CstateUp] state[SSS Setup]
*May 29 05:06:04.958: Vi1 PPP: old[Up] event[PPPReneg] state[SSS Setup]
*May 29 05:06:04.958: %LINEPROTO-5-UPDOWN: Line protocol on Interface Virtual-Access1, changed state to down
*May 29 05:06:04.962: Vi1 PPP SIP segment: Provisioned
*May 29 05:06:04.962: Vi1 PPP SIP segment: if_number 9
*May 29 05:06:04.962: Vi1 PPP SIP segment: sub_if_number 9
*May 29 05:06:04.962: Vi1 PPP SIP segment: ppp_vencap 631BD24C
*May 29 05:06:04.962: Vi1 PPP SIP segment: access id 9F00009B
*May 29 05:06:04.962: Vi1 PPP SIP segment: switch hdl 0
*May 29 05:06:04.962: Vi1 PPP SIP segment: sss circuit 0
*May 29 05:06:04.962: Vi1 PPP SIP segment: lcp magic 62CFF3CF
*May 29 05:06:04.962: Vi1 PPP SIP segment: local term 1
*May 29 05:06:04.962: Vi1 PPP SIP segment: lcp up 1
*May 29 05:06:04.962: Vi1 PPP SIP segment: punt to RP 0
*May 29 05:06:04.962: Vi1 PPP SIP segment: cond debug 1
*May 29 05:06:04.962: Vi1 PPP SIP segment: vp_bound 0
*May 29 05:06:04.962: Vi1 PPP SIP segment: fwded 0
*May 29 05:06:04.962: Vi1 PPP SIP segment: Unbind
*May 29 05:06:04.966: Vi1 PPP: Received SSS-Mgr Need-More-Keys from SSS
*May 29 05:06:04.966: Vi1 PPP: Change SIP state from SSS Setup to Binding
*May 29 05:06:04.966: Vi1 PPP: old[SSS Setup] event[MoreKeys] state[Binding]
*May 29 05:06:04.966: Vi1 PPP: Static Bind peer_type[0]
*May 29 05:06:04.966: Vi1 PPP: Send Message[Static Bind Response]
*May 29 05:06:04.966: Vi1 PPP: Authorization required
*May 29 05:06:04.966: Vi1 PPP: Using dialer call direction
*May 29 05:06:04.966: Vi1 PPP: Treating connection as a callout
*May 29 05:06:04.970: Vi1 PPP: Session handle[4900009E] Session id[155]
*May 29 05:06:04.970: Vi1 LCP: Event[OPEN] State[Initial to Starting]
*May 29 05:06:04.970: Vi1 PPP: No remote authentication for call-out
*May 29 05:06:04.970: Vi1 LCP: O CONFREQ [Starting] id 1 len 10
*May 29 05:06:04.970: Vi1 LCP: MagicNumber 0x62DD547C (0x050662DD547C)
*May 29 05:06:04.970: Vi1 LCP: Event[UP] State[Starting to REQsent]
*May 29 05:06:04.970: Vi1 PPP: Received Static Bind Response from PPP
*May 29 05:06:04.970: Vi1 PPP: Change SIP state from Binding to Up
*May 29 05:06:04.970: Vi1 PPP: old[Binding] event[PPPBindResp] state[Up]
*May 29 05:06:04.970: Vi1 PPP SIP segment: Unprovision
*May 29 05:06:04.970: Vi1 PPP SIP segment: CLEANUP
*May 29 05:06:05.030: Vi1 LCP: I CONFREQ [REQsent] id 1 len 18
*May 29 05:06:05.034: Vi1 LCP: MRU 1492 (0x010405D4)
*May 29 05:06:05.034: Vi1 LCP: AuthProto PAP (0x0304C023)
*May 29 05:06:05.034: Vi1 LCP: MagicNumber 0x3BAA0A4C (0x05063BAA0A4C)
*May 29 05:06:05.034: Vi1 LCP: O CONFNAK [REQsent] id 1 len 8
*May 29 05:06:05.034: Vi1 LCP: MRU 1500 (0x010405DC)
*May 29 05:06:05.034: Vi1 LCP: Event[Receive ConfReq-] State[REQsent to REQsent]
*May 29 05:06:05.034: Vi1 LCP: I CONFACK [REQsent] id 1 len 10
*May 29 05:06:05.034: Vi1 LCP: MagicNumber 0x62DD547C (0x050662DD547C)
*May 29 05:06:05.034: Vi1 LCP: Event[Receive ConfAck] State[REQsent to ACKrcvd]
*May 29 05:06:05.042: Vi1 LCP: I CONFREQ [ACKrcvd] id 2 len 18
*May 29 05:06:05.042: Vi1 LCP: MRU 1500 (0x010405DC)
*May 29 05:06:05.042: Vi1 LCP: AuthProto PAP (0x0304C023)
*May 29 05:06:05.042: Vi1 LCP: MagicNumber 0x3BAA0A4C (0x05063BAA0A4C)
*May 29 05:06:05.042: Vi1 LCP: O CONFACK [ACKrcvd] id 2 len 18
*May 29 05:06:05.042: Vi1 LCP: MRU 1500 (0x010405DC)
*May 29 05:06:05.042: Vi1 LCP: AuthProto PAP (0x0304C023)
*May 29 05:06:05.042: Vi1 LCP: MagicNumber 0x3BAA0A4C (0x05063BAA0A4C)
*May 29 05:06:05.042: Vi1 LCP: Event[Receive ConfReq+] State[ACKrcvd to Open]
*May 29 05:06:05.046: Vi1 PPP: No authorization without authentication
*May 29 05:06:05.046: Vi1 PPP: Phase is AUTHENTICATING, by the peer
*May 29 05:06:05.046: Vi1 PAP: Using hostname from interface PAP
*May 29 05:06:05.046: Vi1 PAP: Using password from interface PAP
*May 29 05:06:05.046: Vi1 PAP: O AUTH-REQ id 1 len 27 from "luser"
*May 29 05:06:05.046: Vi1 LCP: State is Open
*May 29 05:06:05.106: Vi1 PAP: I AUTH-ACK id 1 len 5
*May 29 05:06:05.106: Vi1 PPP SSS: Forwarding request
*May 29 05:06:05.110: Vi1 PPP: Phase is FORWARDING, Attempting Forward
*May 29 05:06:05.110: Vi1 PPP: Queue IPCP code[1] id[1]
*May 29 05:06:05.110: Vi1 PPP: Received SSS-Mgr Connect-Local from SSS
*May 29 05:06:05.110: Vi1 PPP: Phase is ESTABLISHING, Finish LCP
*May 29 05:06:05.114: Vi1 PPP: Phase is UP
*May 29 05:06:05.114: Vi1 IPCP: Protocol configured, start CP. state[Initial]
*May 29 05:06:05.114: Vi1 IPCP: Event[OPEN] State[Initial to Starting]
*May 29 05:06:05.114: Vi1 IPCP: O CONFREQ [Starting] id 1 len 10
*May 29 05:06:05.114: Vi1 IPCP: Address 0.0.0.0 (0x030600000000)
*May 29 05:06:05.114: Vi1 IPCP: Event[UP] State[Starting to REQsent]
*May 29 05:06:05.114: Vi1 PPP: Process pending ncp packets
*May 29 05:06:05.114: Vi1 IPCP: Redirect packet to Vi1
*May 29 05:06:05.114: Vi1 IPCP: I CONFREQ [REQsent] id 1 len 10
*May 29 05:06:05.114: Vi1 IPCP: Address XX.YY.225.104 (0x0306D80EE168)
*May 29 05:06:05.114: Vi1 IPCP: O CONFACK [REQsent] id 1 len 10
*May 29 05:06:05.114: Vi1 IPCP: Address XX.YY.225.104 (0x0306D80EE168)
*May 29 05:06:05.114: Vi1 IPCP: Event[Receive ConfReq+] State[REQsent to ACKsent]
*May 29 05:06:05.114: Vi1 PPP: old[Up] event[LocalTerm] state[Up]
*May 29 05:06:05.118: %LINEPROTO-5-UPDOWN: Line protocol on Interface Virtual-Access1, changed state to up
*May 29 05:06:05.118: Vi1 PPP SIP segment: Update
*May 29 05:06:05.118: Vi1 PPP SIP segment: if_number 0
*May 29 05:06:05.118: Vi1 PPP SIP segment: sub_if_number 0
*May 29 05:06:05.118: Vi1 PPP SIP segment: ppp_vencap 631BD24C
*May 29 05:06:05.118: Vi1 PPP SIP segment: access id 0
*May 29 05:06:05.118: Vi1 PPP SIP segment: switch hdl 0
*May 29 05:06:05.118: Vi1 PPP SIP segment: sss circuit 0
*May 29 05:06:05.118: Vi1 PPP SIP segment: lcp magic 62DD547C
*May 29 05:06:05.118: Vi1 PPP SIP segment: local term 1
*May 29 05:06:05.118: Vi1 PPP SIP segment: lcp up 1
*May 29 05:06:05.118: Vi1 PPP SIP segment: punt to RP 0
*May 29 05:06:05.118: Vi1 PPP SIP segment: cond debug 1
*May 29 05:06:05.118: Vi1 PPP SIP segment: vp_bound 0
*May 29 05:06:05.118: Vi1 PPP SIP segment: fwded 0
*May 29 05:06:05.122: Vi1 IPCP: I CONFNAK [ACKsent] id 1 len 10
*May 29 05:06:05.122: Vi1 IPCP: Address XX.YY.231.205 (0x0306D80EE7CD)
*May 29 05:06:05.122: Vi1 IPCP: O CONFREQ [ACKsent] id 2 len 10
*May 29 05:06:05.122: Vi1 IPCP: Address XX.YY.231.205 (0x0306D80EE7CD)
*May 29 05:06:05.122: Vi1 IPCP: Event[Receive ConfNak/Rej] State[ACKsent to ACKsent]
*May 29 05:06:05.130: Vi1 IPCP: I CONFACK [ACKsent] id 2 len 10
*May 29 05:06:05.130: Vi1 IPCP: Address XX.YY.231.205 (0x0306D80EE7CD)
*May 29 05:06:05.130: Vi1 IPCP: Event[Receive ConfAck] State[ACKsent to Open]
*May 29 05:06:05.142: Vi1 IPCP: State is Open
*May 29 05:06:05.142: Di0 IPCP: Install negotiated IP interface address XX.YY.231.205
*May 29 05:06:05.146: Di0 Added to neighbor route AVL tree: topoid 0, address XX.YY.225.104
*May 29 05:06:05.146: Di0 IPCP: Route not installed to XX.YY.225.104
以及配置的相关部分：
interface ATM0/1/0
no ip address
dsl operating-mode auto
no sh
pvc 0/100
pppoe-client dial-pool-number 1
!
interface dialer0
ip address negotiated
ip mtu 1492
ip nat outside
encapsulation ppp
no cdp enable
ppp authentication pap callin
ppp pap sent-username luser password xxXXxx
dialer pool 1
dialer-group 1
no sh
!
ppp ipcp dns request accept
ppp ipcp address accept
dialer-list 1 protocol ip permit
ip route 0.0.0.0 0.0.0.0 dialer0
!
interface FastEthernet0/0
shutdown
no ip address
!
interface FastEthernet0/1
ip add 192.168.2.1 255.255.255.0
ip nat inside
ip tcp adjust-mss 1452
no sh
!
access-list 100 permit ip 192.168.2.0 0.0.0.255 any
ip nat inside source list 100 interface dialer0 overload
!
!
ip dhcp pool Router
network 192.168.2.0 255.255.255.0
default-router 192.168.2.1
dns-server 8.8.8.8 4.4.4.4
!
我可以从内部网络 ping XX.YY.231.205，但不能从 Cisco 命令行 ping 通。我无法从任何地方访问互联网。
如果有人能告诉我如何正确诊断这个问题，我将不胜感激。