07-07-2003 05:39 AM - edited 03-02-2019 08:40 AM
hi,
we have an 3640 connected over 2xFrameRelayMultipoint and 2xFrameRelayPoint_Point.
The P-P links have a much greater cost than the MultipointInterfaces - but the router always gets the defaultrouter over the Point_point Interfaces -
Any Idea ???
WHY ??
interface Serial0/0
description BR-GRZTR1: FrameRelay to GRZ (Se0/0)
bandwidth 4900
no ip address
encapsulation frame-relay
no ip mroute-cache
logging event subif-link-status
logging event dlci-status-change
load-interval 30
keepalive 5
serial restart-delay 0
frame-relay traffic-shaping
frame-relay lmi-type q933a
!
interface Serial0/0.1 multipoint
description BR-GRZTR1: FR to GRZRBGO1 (Se0/0.1) - PROD
bandwidth 512
ip address 172.16.33.22 255.255.255.252
no ip route-cache same-interface
ip ospf network point-to-multipoint
frame-relay class 1024k
frame-relay interface-dlci 199
!
interface Serial0/0.2 multipoint
description BR-GRZTR1: FR to GRZRBGO2 (Se0/0.2) - BACKUP
bandwidth 512
ip address 172.16.33.122 255.255.255.252
no ip route-cache same-interface
ip ospf network point-to-multipoint
ip ospf cost 1000
frame-relay class 1024k
frame-relay interface-dlci 599
!
interface Serial0/0.299 point-to-point
description BR-GRZTR1: to MPLSRBGOPE01 (Se0/0.299) - PROD
bandwidth 512
ip address 172.16.25.30 255.255.255.252
ip ospf message-digest-key 1 md5 7 011C15145D5F140D26
ip ospf cost 1500
tag-switching mtu 1512
tag-switching ip
frame-relay class mpls_1024k
frame-relay interface-dlci 299
!
interface Serial0/0.699 point-to-point
description BR-GRZTR1: to MPLSRBGOPE02 (Se0/0.699) - BACKUP
bandwidth 512
ip address 172.16.25.130 255.255.255.252
ip ospf message-digest-key 1 md5 7 011C15145D5F140D26
ip ospf cost 2000
tag-switching mtu 1512
tag-switching ip
frame-relay class mpls_1024k
frame-relay interface-dlci 699
!
07-07-2003 05:56 AM
There is no 'ip ospf cost ' statement on interface interface Serial0/0.1 multipoint , without this statement OSPF uses the bandwidth statement , since the bandwidth on this interface is 512 K the cost associated with this would be approx 90 .
Another thing you may want to check is are there OSPF neibors on the all the links , and the cost is used for outbound traffic , you may want to check the cost on the side that you are receiving the default router from .
07-07-2003 06:02 AM
hi,
you are right - so the router should get the defaultroute over s0/0.1 because it has approx cost=90 and all other have a higher cost.
BUT:
it receives the defaultroute over s0/0.299 - and that is my problem !
(could it be that a router sees a P-P interface better than a multipoint ??)
07-07-2003 06:13 AM
How is the default route being propagated ? redistribution ?
could you paste in a 'sh ip o dat external 0.0.0.0 '
07-07-2003 06:29 AM
hi,
thanks for answer - we do a "default-information originate always metric-type 1"
the problem is that i have "shut" the int 0/0.299 and 0/0.699 because we have problems - it´s a productionenviroment.
so i can paste a "sh ip os ....." without 0/0.299 and 0/0.699:
br-grztr1#sh ip ospf data ext 0.0.0.0
OSPF Router with ID (172.16.24.9) (Process ID 65052)
OSPF Router with ID (10.22.208.254) (Process ID 100)
Type-5 AS External Link States
Routing Bit Set on this LSA
LS age: 537
Options: (No TOS-capability, DC)
LS Type: AS External Link
Link State ID: 0.0.0.0 (External Network Number )
Advertising Router: grzrbgo2.rbgooe.at
LS Seq Number: 80008F49
Checksum: 0x10E1
Length: 36
Network Mask: /0
Metric Type: 1 (Comparable directly to link state metric)
TOS: 0
Metric: 1
Forward Address: 0.0.0.0
External Route Tag: 100
Routing Bit Set on this LSA
LS age: 1095
Options: (No TOS-capability, DC)
LS Type: AS External Link
Link State ID: 0.0.0.0 (External Network Number )
Advertising Router: grzrbgo1.rbgooe.at
LS Seq Number: 8000A1EB
Checksum: 0x46E9
Length: 36
Network Mask: /0
Metric Type: 1 (Comparable directly to link state metric)
TOS: 0
Metric: 1
Forward Address: 0.0.0.0
External Route Tag: 100
br-grztr1#
but i even have problems to interpret this:
why is the metric=1 over both advertising router ?
on rbgo1-router it should be approx=90 and over rbgo2 it should be 1000
(thats the interface-cost)
07-07-2003 06:40 AM
are you sure you have ospf neighbors across Serial0/0.2 & Serial0/0.1 ?
do you have access to the routers on both sides of PVC ?
did you look for mismatched ospf network types this would result in mismatched timers , this would not allow the neighbors to become adjacent.
07-07-2003 11:05 PM
hi,
a.) yes - i have ospf neigbors on all 4 int.
b.) yes - i have access on all routers
c.) the networktype ons0/0.1 and 0/0.2 is multipoint on all sides and the
networktype on s0/0.299 and 0/0.699 is point-point on all sides.
one thing to mention:
i have 2 different ospf-processes running on the router which has the "wrong"
defaultroute.
we migrating to mpls, so this distributionsrouter has two links (s0/0.1 and s0/0.2) to the "old" world with ospf process 100 and 2 links (s0/0.299 and 699) to the new mpls core-routers with process-id 65052.
so the distributionsrouter gets the defaultroute over 2 different ospf-processes.
it should install the defaultroute from the "old" routers.
today i have changed the networktype from s0/0.1 and 0/0.2 to point-point.
we will try in 4 hours - perhaps the different networktype between the old and the new world is the issue.
do you know on what parameter a router installs the route in the routingtable if it gets a route over 2 different ospf-processes?
(as you saw we configured different ospf cost - is this enough ?)
07-08-2003 08:05 AM
Ok I think I see the problem
Your default has a tag of 100, the interface s0/0.1 , is in AS 65052 , in order for you to default all your traffic you this interface a router upstream in this
AS will have to generate a default, currently the default is being propagated in AS 100.
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