Routing

Hi Guys

 

There are 3 OSPF routers in the same area connected as shown below

 

On R2 OSPF is running on interfaces connected to R1 and R3

and the other interfaces ge-0/0/2 and ge-0/0/5 are OSPF passive interfaces

so networks 192.168.1.0/24 and 172.32.32.0/24 will be advertised to R1 and R3

 

The requirement:

----------------------------

 

Network 172.32.32.0/24 is required to still be advertised to R1, but shouldn't be advertised to R3, and its interface ge-0/0/5 should stay configured as an OSPF passive interface

 

By which means this can be done???

 

 

                                                  (R3)

                                                     |

                                                     |

                                                     |

(R1) ================= (R2)-----ge-0/0/5 ospf passive - IP address 172.32.32.0/24

                                                     /

                                                    /

                                                  ge-0/0/2 ospf passive - IP address 192.168.1.0/24

 

 

Thanks in Advance 🙂

Hello,

I slighly amended Your diagram for clarity.

 

---

@Eng_Ahmad wrote:

 

 

                                                  (R3)

                                                     |

                                                     |

                                                     |

(R1) =========ge-9/9/9= (R2)-----ge-0/0/5 ospf passive - IP address 172.32.32.0/24

                                                     /

                                                    /

                                                  ge-0/0/2 ospf passive - IP address 192.168.1.0/24

 

 

 

---

Assuming R1 is connected to R2 with a dedicated interface (i.e. ge-9/9/9 as shown aboive on amended diagram), then no-forwarding instance+OSPF export policy+rib-groups for route leaking between no-forwarding instance& inet.0 would accomplish what You want.

Link

http://www.juniper.net/techpubs/en_US/junos10.4/information-products/topic-collections/config-guide-routing/topic-32747.html

(although instance-type is not explicitly configured in this example, the default instance-type is "no-forwarding")

HTH

Thanks

Alex

Thanks aarseniev for the provided information and sorry for the delay from my side in reply.

 

Isn't there any simpler way than this? can't this be done using policy-options or any other idea?

 

Regarding the provided idea , when using another routing instance then this make me have to import interface-routes also inside this other routing instance .. so what if I'm already using another routing instances and using the ((set routing-options interface-routes rib-group inet  RIB_GROUP_NAME)) command to import interface routes inside another instance.

Unfortunately the above command can be applied only on one rib-group so I will not be able to use with several rib-groups.

 

Awaiting your reply and thanks for your support 🙂

 

---

@aarseniev wrote:

Hello,

I slighly amended Your diagram for clarity.

 

---

@Eng_Ahmad wrote:

 

 

                                                  (R3)

                                                     |

                                                     |

                                                     |

(R1) =========ge-9/9/9= (R2)-----ge-0/0/5 ospf passive - IP address 172.32.32.0/24

                                                     /

                                                    /

                                                  ge-0/0/2 ospf passive - IP address 192.168.1.0/24

 

 

 

---

Assuming R1 is connected to R2 with a dedicated interface (i.e. ge-9/9/9 as shown aboive on amended diagram), then no-forwarding instance+OSPF export policy+rib-groups for route leaking between no-forwarding instance& inet.0 would accomplish what You want.

Link

http://www.juniper.net/techpubs/en_US/junos10.4/information-products/topic-collections/config-guide-routing/topic-32747.html

(although instance-type is not explicitly configured in this example, the default instance-type is "no-forwarding")

HTH

Thanks

Alex

---

 

Hello,

 

---

@Eng_Ahmad wrote:

Thanks aarseniev for the provided information and sorry for the delay from my side in reply.

 

Isn't there any simpler way than this? can't this be done using policy-options or any other idea?

 

 

---

"policy-options" do not filter anything, this stanza is used to hold policy-statements. And policy-statements do filter routes _IF_ applied correctly.

Making an OSPF "passive" interface create Type-1 LSA/OSPF Internal route(s) which cannot be filtered with JUNOS policy.

If you export direct routes using OSPF export policy, this wil create Type-5 LSA/OSPF External route(s) which can be filtered _from_ LSDB _to_ route table using OSPF import policy on remote router.

HTH

Thanks

Alex

Yes, I know that policy-options will have no effect unless applied some where, and that what I was asking about, if we can apply a routing policy somewhere to accomplish the requirement.

Ok, no I'm interested to know how to accomplish this using the first suggestion you provided, so could you please provide a sample configuration for this case if possible.

Thanks 🙂

Regards,
Ahmad Rabie

Hello,

Here You go:

 

                                                  (R3)

                                                     |

                                                     |

                                                     |

(R1) ========ge-1/0/6.10== (R2)-----ge-1/0/2.0 ospf passive - IP address 198.18.15.0/30

 

 

The required config on R2:

 

[edit]
aarseniev@R2# show protocols ospf    
area 0.0.0.0 {
    interface ge-1/1/8.2011 {
        interface-type p2p;
    }
    interface lo0.0 {
        interface-type p2p;
        passive;
    }
    interface ge-1/0/2.0 {
        interface-type p2p;
        passive;
    }
}

[edit]
aarseniev@sadok# show routing-instances NF-OSPF 
instance-type no-forwarding;
interface ge-1/1/6.10;
routing-options {
    instance-import inet0->NF-OSPF;
}
protocols {
    ospf {
        export global-ospf-export;
        area 0.0.0.0 {
            interface ge-1/1/6.10 {
                interface-type p2p;
            }
        }
    }
}
[edit]
aarseniev@sadok# show policy-options policy-statement global-ospf-export 
term 10 {
    from protocol ospf;
    then accept;
}

[edit]
aarseniev@sadok# show policy-options policy-statement inet0->NF-OSPF        
term 1 {
    from {
        instance master;
        protocol ospf;
    }
    then accept;
}

 Verification:

 

- 198.18.15.0/30 should be visible as OSPF route on R3 BUT it is NOT visible as OSPF route on R1:

 

aarseniev@R3> show route protocol ospf 198.18.15.0/30 

inet.0: 26 destinations, 27 routes (26 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

198.18.15.0/30     *[OSPF/10] 1d 19:50:01, metric 1
                    > to 198.18.22.1 via ge-1/1/8.2011

 

aarseniev@R1> show route protocol ospf 198.18.15.0/30 

aarseniev@R1>  

 HTH

Thanks

Alex