10-13-2002 07:42 PM - edited 03-02-2019 02:02 AM
I have configured my Cisco 1720 Router with a primary Serial interface and a
dialer profile tied to a BRI as a backup interface. I am using both the backup load and backup delay commands on the primary Serial interface, to trigger the bri in event of excess traffic load and primary line failure, however the backup interface never seems to trigger, even though I've set a very low threshold for traffic load on the primary interface. Is it possible that the backup
load command only works with similar interfaces? Need help..
thanks
10-14-2002 03:19 AM
Hi,
here is a sample configuration which should work.
interface Serial0/0
bandwidth 128
backup interface Dialer2
backup load 60 40
no ip address
interface Bri0/0
description *** ***
no ip address
no ip directed-broadcast
encapsulation ppp
dialer pool-member 2
isdn switch-type basic-net3
no cdp enable
ppp authentication chap
!
!
interface Dialer2
description *** BoD ***
bandwidth 64
ip address 10.65.65.10 255.255.255.252
no ip directed-broadcast
encapsulation ppp
dialer remote-name bod_location_b
dialer string 0511...
dialer load-threshold {1-255} {outbound | inbound | either}
dialer pool 2
dialer-group 2
ppp authentication chap
ppp chap hostname bod_loaction_a
ppp multilink
I the dialer-list you should enable ip any any first, to check if it is working.
Check also with the "debug dialer" command if the ISDN tries to establish
a call, maybe you have a problem with ISDN. If it is fitting in your flash
memory, take at least IOS version 12.2(7) or higher for ISDN.
Hope this will help
regards Ulrich Marzoli
10-15-2002 10:37 PM
thankx for the input ulrich,
tried ur sample config but was still unsuccessful, the backup interface will trigger only if the primary interface fails , but never when traffic exceeds the maximum load specified, the following is my router config. I even did a debug isdn, but saw zero isdn activity.Could it be because I am using a sub interface for my primary serial frame relay link?
any ideas?...
thanx again
sh ru
Building configuration...
Current configuration:
!
version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname BT9_RT1720_01
!
!
username KJG_RT3640_01
username RG_Kuala_Lumpur
!
!
!
!
memory-size iomem 15
clock timezone SGT 8
ip subnet-zero
no ip domain-lookup
no ip dhcp conflict logging
ip dhcp excluded-address 10.31.34.1 10.31.34.19
ip dhcp excluded-address 10.31.34.51 10.31.34.126
!
ip dhcp pool bt9
network 10.31.34.0 255.255.255.128
default-router 10.31.34.1
dns-server 10.31.29.10 10.0.8.1
domain-name kjg
lease 365
!
isdn switch-type basic-net3
!
!
!
interface Loopback0
ip address 202.178.62.21 255.255.255.0
!
interface Loopback1
ip address 10.10.10.10 255.255.255.255
!
interface Serial0
bandwidth 32
backup delay 1 300
backup interface Dialer1
backup load 30 10
no ip address
encapsulation frame-relay IETF
no fair-queue
frame-relay class bt9
frame-relay lmi-type ansi
!
interface Serial0.1 point-to-point
description KK Batu 9 Cheras_Hulu Langat to Hospital Kajang
ip address 202.178.63.34 255.255.255.252
ip ospf message-digest-key 10 md5 7 0524222C7067642E4B
frame-relay interface-dlci 41
!
interface BRI0
no ip address
encapsulation ppp
dialer pool-member 1
dialer pool-member 2
isdn switch-type basic-net3
no cdp enable
ppp authentication chap
!
interface FastEthernet0
ip address 10.31.34.1 255.255.255.128
speed auto
!
interface Dialer1
bandwidth 128
ip unnumbered Loopback0
encapsulation ppp
dialer remote-name KJG_RT3640_01
dialer pool 1
dialer idle-timeout 1800
dialer string 87321292
dialer load-threshold 200 either
dialer-group 1
no cdp enable
ppp authentication chap
ppp chap hostname BT9_RT1720_01
ppp multilink
!
interface Dialer2
ip unnumbered Loopback1
encapsulation ppp
dialer remote-name RG_Kuala_Lumpur
dialer pool 2
dialer idle-timeout 20
dialer string 20529946
dialer-group 1
ppp authentication chap
!
router ospf 2
log-adjacency-changes
area 2 authentication message-digest
area 2 nssa
passive-interface BRI0
passive-interface Dialer1
network 10.31.34.0 0.0.0.127 area 2
network 202.178.63.32 0.0.0.3 area 2
ip classless
ip route 0.0.0.0 0.0.0.0 Dialer1 200
no ip http server
map-class frame-relay bt9
frame-relay traffic-rate 32000 64000
no frame-relay adaptive-shaping
frame-relay priority-group 1
logging 202.178.0.98
logging 202.178.10.10
logging 10.0.11.8
priority-list 1 protocol ip high
dialer-list 1 protocol ip permit
!
end
BT9_RT1720_01#
rgds,
shahrun
10-14-2002 04:46 AM
You must have a functional dialer configuration before "backup interface" can use it. To test, delete the "backup interface" command and see if the dialer activates (the only thing which should stand between the dialer and a backup call should be the "backup interface" command disabling the dialer.
Warning note: removing the backup interface line will also delete all other backup parameters on the interface, so you'll need to add everything back once you get the dialer working correctly.
If you need help finding your configuration error, try posting a sanitized version of your configuration. There are examples of working configurations on www.cisco.com and in the "Listings from my book" section of my website. See in particular Listing 4-4.
Good luck and good hunting!
Vincent C Jones
10-15-2002 08:38 PM
thankx for the input guys,
tried ur sample config but was still unsuccessful, the backup interface will trigger only if the primary interface fails , but never when traffic exceeds the maximum load specified, the following is my router config. I even did a debug isdn, but saw zero isdn activity.Could it be because I am using a sub interface for my primary serial frame relay link?
any ideas?...
thanx again
sh ru
Building configuration...
Current configuration:
!
version 12.1
service timestamps debug uptime
service timestamps log uptime
no service password-encryption
!
hostname BT9_RT1720_01
!
!
username KJG_RT3640_01
username RG_Kuala_Lumpur
!
!
!
!
memory-size iomem 15
clock timezone SGT 8
ip subnet-zero
no ip domain-lookup
no ip dhcp conflict logging
ip dhcp excluded-address 10.31.34.1 10.31.34.19
ip dhcp excluded-address 10.31.34.51 10.31.34.126
!
ip dhcp pool bt9
network 10.31.34.0 255.255.255.128
default-router 10.31.34.1
dns-server 10.31.29.10 10.0.8.1
domain-name kjg
lease 365
!
isdn switch-type basic-net3
!
!
!
interface Loopback0
ip address 202.178.62.21 255.255.255.0
!
interface Loopback1
ip address 10.10.10.10 255.255.255.255
!
interface Serial0
bandwidth 32
backup delay 1 300
backup interface Dialer1
backup load 30 10
no ip address
encapsulation frame-relay IETF
no fair-queue
frame-relay class bt9
frame-relay lmi-type ansi
!
interface Serial0.1 point-to-point
description KK Batu 9 Cheras_Hulu Langat to Hospital Kajang
ip address 202.178.63.34 255.255.255.252
ip ospf message-digest-key 10 md5 7 0524222C7067642E4B
frame-relay interface-dlci 41
!
interface BRI0
no ip address
encapsulation ppp
dialer pool-member 1
dialer pool-member 2
isdn switch-type basic-net3
no cdp enable
ppp authentication chap
!
interface FastEthernet0
ip address 10.31.34.1 255.255.255.128
speed auto
!
interface Dialer1
bandwidth 128
ip unnumbered Loopback0
encapsulation ppp
dialer remote-name KJG_RT3640_01
dialer pool 1
dialer idle-timeout 1800
dialer string 87321292
dialer load-threshold 200 either
dialer-group 1
no cdp enable
ppp authentication chap
ppp chap hostname BT9_RT1720_01
ppp multilink
!
interface Dialer2
ip unnumbered Loopback1
encapsulation ppp
dialer remote-name RG_Kuala_Lumpur
dialer pool 2
dialer idle-timeout 20
dialer string 20529946
dialer-group 1
ppp authentication chap
!
router ospf 2
log-adjacency-changes
area 2 authentication message-digest
area 2 nssa
passive-interface BRI0
passive-interface Dialer1
network 10.31.34.0 0.0.0.127 area 2
network 202.178.63.32 0.0.0.3 area 2
ip classless
ip route 0.0.0.0 0.0.0.0 Dialer1 200
no ip http server
map-class frame-relay bt9
frame-relay traffic-rate 32000 64000
no frame-relay adaptive-shaping
frame-relay priority-group 1
logging 202.178.0.98
logging 202.178.10.10
logging 10.0.11.8
priority-list 1 protocol ip high
dialer-list 1 protocol ip permit
!
end
BT9_RT1720_01#
10-15-2002 11:09 PM
Hi,
I think that you should configure the backup commands on your sub-interface.
Be aware that you are using fram-relay and when the PVC is down your interface could be up. So the router won't dailout.
Regards,
Mario
10-16-2002 12:29 AM
hi mario,
actually i tried the backup interface on the serial interface, and fail-over backup
kicked in, because it is tracking the line protocol(so even though the serial is up, the backup will trigger because line protocol is down). So, I have no problem with backup failover,just the traffic load backup. Also,
to do a backup load on the sub interface is not possible as the backup command only allows backup delay and backup interface options, and I am running IOS version 12.1.3.Is it possible with more recent versions?
thanx..
10-16-2002 03:32 AM
Hi,
just reviewed your configuration and I believe the problem is that you didn't
have included the Loopback network in the OSPF routing process. So in case
of the backupload is exceeded the ISDN will only establish a call when there
is interesting traffic but there is none, because you didn't have a route pointing
in direction of the dialer interface. The floating static default route only kicks
in when the leased line fails, that#s why the backup function works.
Including the Loopback network in the OSPF process will let open the ISDN
connection via the OSPF Hello packets, and than the OSPF routing updates
will advertise also all networks over ISDN.
You also should ensure that in case both connections are up (the serial and
the ISDN connection) that the metrics are equal and the sessions were
load-balanced over the serial and the ISDN connection otherwise it will not
be working properly.
regards Ulrich Marzoli
10-16-2002 03:40 AM
HI,
I've been searching on CCO and as far as i can found that there is no support for the "backup load" command on an sub-interface which is on a frame-relay encapsulation.
See the following URL:
Regard,
Mario
10-16-2002 11:43 PM
hey mario,
that's right, no such command on a sub interface and there should'nt be any
with more recent versions...anyways..as ulrich advised, my problem was with
my loopback network route. but thanx all the same!
10-16-2002 11:38 PM
Hi ulrich,
thanx, for the advice, u were right about the ospf hello packets. I added in the loopback networks and the backup interface kicked off instantly. However, I am only seeing output traffic thru the backup interface, as most of the input traffic(which consumes the bandwidth most) keeps flowing thru the small frame relay pipe, even though I've set a similar metric for both routes. I suppose this is the standard nature in which backup load operates. I just
hope to able to tune the traffic flow so that the load is really balanced.
anyways thanx again for the helpful info
10-17-2002 12:46 AM
Hi,
I hope you have added the loopback interface on the other router as well to
the OSPF process, otherwise the router can not built an OSPF neighboring
and no route informations will be exchanged. Also the metric on the other router must be adjusted for load-balancing. Then all should work well.
regards Ulrich Marzoli
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