【正文】 以下是相關(guān)命令：任務(wù) 命令指定主線路改變后，次線路狀態(tài)發(fā)生改變的延遲時(shí)間 backup delay {enabledelay | never} {disabledelay | never}指定一個(gè)接口作為備份接口 backup interface type numberhostname c2522rb!enable secret 5 $1$J5vn$ceYDe2FwPhrZi6qsIIz6g0enable password cisco!username c4700 password 0 ciscoip subnetzerochatscript ciscodefault AT TIMEOUT 30 OK ATDT \T TIMEOUT 30 CONNECT \cchatscript reset atz!interface Ethernet0ip address no ip mroutec。當(dāng)主接口連接發(fā)生故障時(shí)，端口狀態(tài)為down，則激活備份接口，完成數(shù)據(jù)通信。相關(guān)命令如下：任務(wù) 命令設(shè)置路由器與modem的接口指令 chatscript scriptname EXPECT SEND EXPECT SEND (etc.)設(shè)置端口在掛斷前的等待時(shí)間 dialer idletimeout seconds設(shè)置協(xié)議地址與電話號(hào)碼的映射 dialer map protocol nexthopaddress [name hostname] [broadcast] [modemscriptmodemregexp] [systemscript systemregexp] [dialstring]設(shè)置電話號(hào)碼 dialer string dialstring指定在特定線路下路由器默認(rèn) 使用的chatscript script {dialer|reset} scriptnameRouter1:hostname Router1!enable secret 5 $1$QKI7$wXjpFqC74vDAyKBUMallw/ !username Router2 password ciscochatscript ciscodefault AT TIMEOUT 30 OK ATDT \T TIMEOUT 30 CONNECT \c!interface Ethernet0ip address !interface Async1ip address encapsulation pppasync default routingasync mode dedicateddialer inbanddialer idletimeout 60dialer map ip name Router2 modemscript ciscodefault 573dialergroup 1ppp authentication chap!ip route dialerlist 1 protocol ip permit !line con 0line aux 0modem InOutmodem autoconfigure discoveryflowcontrol hardware Router2:hostname Router2!enable secret 5 $1$F6EV$5U8puzNt2/.!username Router1 password cisco!interface Ethernet0ip address !interface Async1ip address encapsulation pppasync default routingasync mode dedicateddialer inbanddialer idletimeout 60dialer map ip name Router1dialergroup 1ppp authentication chap!ip route dialerlist 1 protocol ip permit!line con 0line aux 0modem InOutmodem autoconfigure discoveryflowcontrol hardware!相關(guān)調(diào)試命令：debug dialerdebug ppp authenticationdebug ppp errordebug ppp negotiationdebug ppp packetshow dialer 3. 異步撥號(hào)備份DDN專線：此例主連接采用DDN專線，備份線路為電話撥號(hào)。同時(shí)在Router2中應(yīng)建立一個(gè)用戶，以對(duì)端路由器主機(jī)名作為用戶名，即用戶名應(yīng)為Router1。Router1撥號(hào)連接到Router2。這里使用tac作為關(guān)鍵字。 aaa accounting exec startstop tacacs+為與網(wǎng)絡(luò)相關(guān)的服務(wù)需求運(yùn)行記帳包括SLIP,PPP,PPP NCPs,+服務(wù)器。全局設(shè)置：任務(wù) 命令設(shè)置用戶名和密碼 username username password password設(shè)置用戶的IP地址池 ip local pool {default | poolname lowipaddress [highipaddress]}指定地址池的工作方式 ip addresspool [dhcpproxyclient | local]基本接口設(shè)置命令：任務(wù) 命令設(shè)置封裝形式為PPP encapsulation ppp啟動(dòng)異步口的路由功能 async default routing設(shè)置異步口的PPP工作方式 async mode {dedicated | interactive}設(shè)置用戶的IP地址 peer default ip address {ipaddress | dhcp | pool [poolname]}設(shè)置IP地址與Ethernet0相同 ip unnumbered ethernet0line撥號(hào)線設(shè)置：任務(wù) 命令設(shè)置modem的工作方式 modem {inout|dialin}自動(dòng)配置modem類型 modem autoconfig discovery設(shè)置撥號(hào)線的通訊速率 speed speed設(shè)置通訊線路的流控方式 flowcontrol {none | software [lock] [in | out] | hardware [in | out]}連通后自動(dòng)執(zhí)行命令 automand mand訪問服務(wù)器設(shè)置如下：Router:hostname Routerenable secret 5 $1$EFqU$tYLJLrynNUKzE4bx6fmH// !interface Ethernet0ip address !interface Async1ip unnumbered Ethernet0encapsulation pppkeepalive 10async mode interactivepeer default ip address pool Cisco2511Group142!ip local pool Cisco2511Group142 !line con 0exectimeout 0 0password cisco!line 1 16modem InOutmodem autoconfigure discoveryflowcontrol hardware!line aux 0transport input allline vty 0 4password cisco!end 相關(guān)調(diào)試命令：show interfaceshow line. Access Server通過Tacacs服務(wù)器實(shí)現(xiàn)安全認(rèn)證：使用一臺(tái)WINDOWS NT服務(wù)器作為Tacacs服務(wù)器，,運(yùn)行Cisco2511隨機(jī)帶的Easy ACS .相關(guān)設(shè)置：任務(wù) 命令激活A(yù)AA訪問控制 aaa newmodel用戶登錄時(shí)默認(rèn)起用Tacacs+做AAA認(rèn)證 aaa authentication login default tacacs+列表名為no_tacacs使用ENABLE口令做認(rèn)證 aaa authentication login no_tacacs enable在運(yùn)行PPP的串行線上采用Tacacs+做認(rèn)證 aaa authentication ppp default tacacs+由TACACS+服務(wù)器授權(quán)運(yùn)行EXEC aaa authorization exec tacacs+由TACACS+服務(wù)器授權(quán)與網(wǎng)絡(luò)相關(guān)的服務(wù)請(qǐng)求。電話網(wǎng)絡(luò)的應(yīng)用一般可分為兩種類型，一種是同等級(jí)別機(jī)構(gòu)之間以按需撥號(hào)(DDR)的方式實(shí)現(xiàn)互連，一種是ISP為撥號(hào)上網(wǎng)為用戶提供的遠(yuǎn)程訪問服務(wù)的功能。set system c765c765 set multidestination onc765 set switch net3c765 set ppp multilink onc765 cd lanc765AN set ip routing onc765AN set ip address c765AN set ip netmask c765:LAN set briding offc765:LANcdc765 set user remotenetNew user remotenet being createdc765:remotenet set ip routing onc765:remotenet set bridging offc765:remotenet set ip framing nonec765:remotenet set ppp clientname 263c765:remotenet set ppp password clientEnter new Password: 263ReType new Password: 263c765:remotenet set ppp authentication out nonec765:remotenet set ip address c765:remotenet set ip netmask c765:remotenet set ppp address negotiation local onc765:remotenet set ip pat onc765:remotenet set ip route destination c765:remotenet set number 2633c765:remotenet set active命令描述如下： 任務(wù) 命令 設(shè)置路由器系統(tǒng)名稱 set system c765 允許路由器呼叫多個(gè)目的地 set multidestination on 設(shè)置ISDN交換機(jī)類型為NET3 set switch net3 允許點(diǎn)到點(diǎn)間多條通道連接實(shí)現(xiàn)負(fù)載均衡 set ppp multilink on 關(guān)掉橋接 set briding off 建立用戶預(yù)制文件用于設(shè)置撥號(hào)連接參數(shù) 可以設(shè)置多個(gè)用戶預(yù)制文件用于相同的物理端口對(duì)應(yīng)于不同的連接。 dialer map protocol address name hostname class classname dialstring 設(shè)置接口支持PPP回?fù)?ppp callback accept 在全局模式下為PPP回?fù)茉O(shè)置映射類別 mapclass dialer classname 通過查找注冊(cè)在dialer map里的主機(jī)名來(lái)決定回?fù)? dialer callbackserver [username] 設(shè)置接口要求PPP回?fù)?ppp callback request 設(shè)置如下：Router1:hostname router1 user router2 password cisco ! isdn switchtype basicnet3 ! interface bri 0 ip address encapsulation ppp dialer map ip name router2 class s3 572 dialer loadthreshold 80 ppp callback accept ppp multilink dialergroup 1 ppp authentication chap ！ mapclass dialer s3 dialer callbackserver username dialerlist 1 protocol ip permit ! Router2: hostname router2 user router1 password cisco ! isdn switchtype basicnet3 ! interface bri 0 ip address encapsulation ppp dialer map ip name router1 571 dialer loadthreshold 80 ppp callback request ppp multilink dialerg