Routing

Hi, I have a simple topology :

R1 ge-0/0/3  - ge-0/0/3 R2

R1  - ABR connected to area 0 and 1. R2 in area 1. I try to advertise default route to R2, but R1 doesn't do it.

root@R1> show ospf database

    OSPF database, Area 0.0.0.0
 Type       ID               Adv Rtr           Seq      Age  Opt  Cksum  Len
Router  *1.1.1.1          1.1.1.1          0x80000004   351  0x22 0xc15f  36
Summary *1.1.1.2          1.1.1.1          0x80000001   860  0x22 0x3df5  28
Summary *192.168.1.0      1.1.1.1          0x80000006   865  0x22 0xae1a  28

    OSPF database, Area 0.0.0.1
 Type       ID               Adv Rtr           Seq      Age  Opt  Cksum  Len
Router  *1.1.1.1          1.1.1.1          0x80000007   351  0x20 0xad9e  36
Router   1.1.1.2          1.1.1.2          0x8000000c   340  0x20 0x70c1  48
Network  192.168.1.2      1.1.1.2          0x80000002   868  0x20 0x259b  32
Summary *1.1.1.1          1.1.1.1          0x80000002  1220  0x20 0x59dc  28

Attachment(s)

R1.txt   806 B 1 version

R2.txt   665 B 1 version

Hi,

nothing wrong with your configuration. I tried same and gives me same result. When I tried to connect 3rd router to R1 in same area 0. it starts to send default route to R2.

root@R1# run show ospf database area 0

    OSPF link state database, Area 0.0.0.0
 Type       ID               Adv Rtr           Seq      Age  Opt  Cksum  Len
Router  *10.0.6.1         10.0.6.1         0x80000020    41  0x22 0x25b1  36
Summary *10.0.4.0         10.0.6.1         0x80000008    41  0x22 0x44d3  28
Summary *10.0.4.4         10.0.6.1         0x80000009    41  0x22 0x1004  28
Summary *10.0.4.8         10.0.6.1         0x80000006    41  0x22 0xf71a  28
Summary *10.0.6.2         10.0.6.1         0x80000006    41  0x22 0x26ed  28

root@R1# run show ospf database area 0  

    OSPF link state database, Area 0.0.0.0
 Type       ID               Adv Rtr           Seq      Age  Opt  Cksum  Len
Router   10.0.3.3         10.0.3.3         0x80000003   216  0x22 0x5a09  84
Router  *10.0.6.1         10.0.6.1         0x80000022   255  0x22 0xb7fc  36
Network *10.0.4.14        10.0.6.1         0x80000001   255  0x22 0xee0   32
Summary *10.0.4.0         10.0.6.1         0x80000009   247  0x22 0x42d4  28
Summary *10.0.4.4         10.0.6.1         0x80000009   310  0x22 0x1004  28
Summary *10.0.4.8         10.0.6.1         0x80000006   310  0x22 0xf71a  28
Summary *10.0.6.2         10.0.6.1         0x80000006   310  0x22 0x26ed  28

- May be because the Adv Rtr is R1 in all area 0 database so it detect no need to advertise default route but when new entry for R3 appears in Adv Rtr it started to send default route

Regards,

Mohamed Elhariry

JNCIE-M/T # 1059, CCNP & CCIP

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Hello there

http://www.juniper.net/techpubs/en_US/junos10.0/information-products/topic-collections/config-guide-routing/routing-configuring-ospf-areas.html

The JUNOS Software supports active backbone detection. Active backbone detection is implemented to verify that area border routers are connected to the backbone. If the connection to the backbone area is lost, then the routing device’s default metric is not advertised,

Try this:

set protocols ospf no-active-backbone

This is hidden command, you have to type it in full from your keyboard.

HTH

Rgds

Alex

Thanks it works!