> Date: Thu, 19 Jul 2001 15:50:38 -0400 > From: "Paul Werner" > Subject: Re: Subject: Why ISDN backup line come up ? [7:12920] > ------SNIP------------- I will see if I can post an > improved/enhanced config in a separate post, possibly later > today as time permits. I went ahead and took your existing configs and preserved as much as I could from them. I added the functionality of dialer profiles to the config. This gave three direct benefits. First, your ISDN interface will no longer be in a down status because it is a named standby interface. Second, it allows you to use the ISDN interface to possibly back up a second serial line should you install one later. Lastly, through the use of Cisco magic and a few extra lines of configuration, I was also able to set up your BRI interface to act as a Bandwidth on demand interface in the event that your primary WAN link gets congested. Here they are: RouterA#sh ru Building configuration... Current configuration : 1497 bytes ! version 12.2 no service single-slot-reload-enable service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname RouterA ! enable password cisco ! username RouterB password 0 cisco ip subnet-zero no ip finger no ip domain-lookup ! isdn switch-type basic-5ess ! ! interface Loopback0 ip address 172.16.128.49 255.255.255.255 ! interface Ethernet0 ip address 192.168.1.83 255.255.255.0 no ip route-cache no ip mroute-cache ! interface Serial0 description "Leased link to RouterB" bandwidth 128 backup delay 5 10 backup interface Dialer1 backup load 50 10 ip address 172.16.128.17 255.255.255.252 no ip route-cache no ip mroute-cache clockrate 148000 ! interface Serial1 no ip address no ip route-cache no ip mroute-cache shutdown ! interface BRI0 description "Backup link to RouterB" no ip address encapsulation ppp dialer pool-member 1 isdn switch-type basic-5ess ppp authentication chap no fair-queue ppp multilink ! interface Dialer1 ip unnumbered Loopback0 dialer pool 1 dialer remote-name RouterB dialer string 88001 dialer-group 1 ! router rip network 172.16.0.0 network 192.168.1.0 ! ip classless no ip http server ! dialer-list 1 protocol ip permit ! ! line con 0 transport input none line aux 0 line vty 0 4 password cisco login ! end Here is B: RouterB#sh ru Building configuration... Current configuration : 1790 bytes ! version 12.2 no service single-slot-reload-enable service timestamps debug uptime service timestamps log uptime no service password-encryption ! hostname RouterB ! enable password cisco ! username RouterA password 0 cisco ip subnet-zero no ip finger no ip domain-lookup ! no ip dhcp-client network-discovery isdn switch-type basic-5ess ! ! interface Loopback0 ip address 172.16.128.50 255.255.255.255 ! interface Ethernet0 mac-address 0000.0c00.2520 ip address 192.168.2.83 255.255.255.0 no ip route-cache no ip mroute-cache ! interface Serial0 description "Leased link to RouterA" bandwidth 128 backup delay 5 10 backup interface Dialer1 backup load 50 10 ip address 172.16.128.18 255.255.255.252 no ip route-cache no ip mroute-cache ! interface Serial1 no ip address no ip route-cache no ip mroute-cache shutdown ! interface BRI0 description "Backup connectivity to RouterA " no ip address encapsulation ppp no ip route-cache no ip mroute-cache dialer pool-member 1 isdn switch-type basic-5ess no fair-queue ppp authentication chap ppp multilink ! interface Dialer1 ip unnumbered Loopback0 dialer pool 1 dialer remote-name RouterA dialer string 87001 dialer-group 1 ! router rip network 172.16.0.0 network 192.168.2.0 ! ip classless no ip http server ! dialer-list 1 protocol ip permit ! ! line con 0 logging synchronous transport input none line aux 0 line vty 0 4 password cisco login ! end The testing for the first part was to get an autoping going for 20,000 pings. Once it go started, I pulled out the serial connection. Prior to doing this, I turned on the following debugs: debug isdn q931 debug dialer debug ppp neg None of the debugs were necessary, unless something didn't work; I just thought it was fascinating to watch so much business go by while the interface was changing state. For brevity, I omitted all debugs. Here goes: RouterB#pi Protocol [ip]: Target IP address: 192.168.1.83 Repeat count [5]: 20000 Datagram size [100]: Timeout in seconds [2]: Extended commands [n]: Sweep range of sizes [n]: Type escape sequence to abort. Sending 20000, 100-byte ICMP Echos to 192.168.1.83, timeout is 2 seconds: !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!..................!!!!!!!!!!!!!!!!!! !!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!! !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! !!!!!! The dots above represented several things. It was the time required for the router to figure out the primary interface was down and the time I ordered it to wait until the backup came online. Keep in mind the typical keepalive is set for 10 seconds. When I plugged the serial interface back in, the transition was seamless and no packets were dropped. To simulate the second test, I telnetted to the loopback interface of each router and got a TTCP session going between the routers over the serial interface. if you are unfamiliar with TTCP, I recommend you do a search on CCO for this testing tool. I monitored the serial interface and when the load hit approximately 126/255, it brought the BRI link online. It stayed online until the load dropped down to my preset value. Since this config essentially frees up the BRI interface, it can also do the same duty for serial 1 if it is brought online. Through the use of the priority command in the dialer pool statement, you can bias which dialer interface will have priority of operation should bandwidth on demand on Serial 0 be needed while backup interface operations on Serial 1 are required. HTH, Paul Werner ________________________________________________ Get your own "800" number Voicemail, fax, email, and a lot more http://www.ureach.com/reg/tag Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=13061&t=13061 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
