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Routing between PE and CE

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  • 1.  Routing between PE and CE

    Posted 03-07-2020 11:57

    PC-CE.JPG

    set system host-name MX-PE1
    
    set interfaces ge-0/0/0 unit 0 family inet address 10.10.10.1/24
    set interfaces ge-0/0/1 unit 0 family inet address 172.16.10.1/24
    set interfaces ge-0/0/1 unit 0 family mpls
    set interfaces lo0 unit 0 family inet address 22.22.22.22/32
    set interfaces lo0 unit 10 family inet address 99.99.99.99/24
    
    Facing MX-P
    set protocols ospf traffic-engineering
    set protocols ospf area 0.0.0.20 interface ge-0/0/1.0
    set protocols ospf area 0.0.0.20 interface lo0.0
    
    set protocols rsvp interface all
    set protocols ldp interface ge-0/0/1.0
    
    set routing-options autonomous-system 65200
    
    set protocols bgp group ToMXPE2 type internal
    set protocols bgp group ToMXPE2 local-address 22.22.22.22
    set protocols bgp group ToMXPE2 family inet unicast
    set protocols bgp group ToMXPE2 family inet-vpn any
    set protocols bgp group ToMXPE2 peer-as 65200
    set protocols bgp group ToMXPE2 neighbor 44.44.44.44
    
    Facing MX-CE1
    set routing-instances CustA instance-type vrf
    set routing-instances CustA interface ge-0/0/0.0
    set routing-instances CustA interface lo0.10
    set routing-instances CustA route-distinguisher 200:10
    set routing-instances CustA vrf-target import target:2000:2000
    set routing-instances CustA vrf-target export target:2000:2000
    set routing-instances CustA protocols ospf export exportBGP
    set routing-instances CustA protocols ospf area 0.0.0.10 interface ge-0/0/0.0
    
    set policy-options policy-statement exportBGP term t1 from protocol bgp
    set policy-options policy-statement exportBGP then accept
    

    Why ospf not needed to redistribute into bgp to be carried over to MX-PE2 as cisco does?

    root@MX-CE2> show route protocol bgp
    
    inet.0: 7 destinations, 7 routes (7 active, 0 holddown, 0 hidden)
    + = Active Route, - = Last Active, * = Both
    
    10.10.10.0/24      *[BGP/170] 01:21:01, localpref 100
                          AS path: 65004 65200 I, validation-state: unverified
                        > to 20.20.20.1 via ge-0/0/1.0
    11.11.11.11/32     *[BGP/170] 01:21:01, localpref 100
                          AS path: 65004 65200 I, validation-state: unverified
                        > to 20.20.20.1 via ge-0/0/1.0
    99.99.99.0/24      *[BGP/170] 01:21:01, localpref 100
                          AS path: 65004 65200 I, validation-state: unverified
                        > to 20.20.20.1 via ge-0/0/1.0
    99.99.99.99/32     *[BGP/170] 01:21:01, localpref 100
                          AS path: 65004 65200 I, validation-state: unverified
                        > to 20.20.20.1 via ge-0/0/1.0
    

    thanks !!



  • 2.  RE: Routing between PE and CE

     
    Posted 03-07-2020 20:52

    Hi

     

    Please check below link which has some information on why we do not need to redistribute the ospf route into bgp:

     

    https://www.juniper.net/documentation/en_US/junose15.1/topics/concept/mbgp-ospf-routes-distribution-pe-ce-router-overview.html

     

     



  • 3.  RE: Routing between PE and CE

    Posted 03-08-2020 08:37

    thanks for the information.

    Here I am more interested in 11.11.11.11 which originates from MX-CE1. I did not redistribute it, how does MX-CE2 see it ?



  • 4.  RE: Routing between PE and CE

    Posted 03-07-2020 23:33

    Hello,

     


    @gongyayu wrote:

    Why ospf not needed to redistribute into bgp to be carried over to MX-PE2 as cisco does?

    root@MX-CE2> show route protocol bgp
    
    inet.0: 7 destinations, 7 routes (7 active, 0 holddown, 0 hidden)
    + = Active Route, - = Last Active, * = Both
    
    10.10.10.0/24      *[BGP/170] 01:21:01, localpref 100
                          AS path: 65004 65200 I, validation-state: unverified
                        > to 20.20.20.1 via ge-0/0/1.0
    11.11.11.11/32     *[BGP/170] 01:21:01, localpref 100
                          AS path: 65004 65200 I, validation-state: unverified
                        > to 20.20.20.1 via ge-0/0/1.0
    99.99.99.0/24      *[BGP/170] 01:21:01, localpref 100
                          AS path: 65004 65200 I, validation-state: unverified
                        > to 20.20.20.1 via ge-0/0/1.0
    99.99.99.99/32     *[BGP/170] 01:21:01, localpref 100
                          AS path: 65004 65200 I, validation-state: unverified
                        > to 20.20.20.1 via ge-0/0/1.0
    

     


     

    If You are asking about routes 10.10.10.0/24,  99.99.99.0/24 and 99.99.99.99/32 then they are NOT OSPF routes in PE1.

    They are covered by "protocols ospf area X interface BLAH.blah" statement but they are direct routes in PE1 VRF table.

    And JUNOS "vrf-target" knob redistributes direct+static routes as expected.

    HTH

    Thx

    Alex 

     

     



  • 5.  RE: Routing between PE and CE

    Posted 03-08-2020 08:41

    I am interested in 11.11.11.11 which originates from MX-CE1 and advertises via OSPF.

     

    thanks !!



  • 6.  RE: Routing between PE and CE
    Best Answer

     
    Posted 03-08-2020 10:02

    Why ospf not needed to redistribute into bgp to be carried over to MX-PE2 as cisco does?

    <Vishal> For the route learned from CE (local route) you don't need specific policy to advertise those route to remote PE. All the local routes will be advertised to remote PE unless to apply a specific export policy.

    Refer the Example Below:


    set logical-systems r1 routing-instances test instance-type vrf
    set logical-systems r1 routing-instances test interface xe-1/3/1.1
    set logical-systems r1 routing-instances test route-distinguisher 100:11111
    set logical-systems r1 routing-instances test vrf-target target:100:111111  <<< no export policy
    set logical-systems r1 routing-instances test protocols ospf export mpbgp_to_ospf
    set logical-systems r1 routing-instances test protocols ospf area 0.0.0.0 interface xe-1/3/1.1


    labroot@rigel-re0# run show route logical-system r1 table test.inet.0

    test.inet.0: 6 destinations, 8 routes (6 active, 0 holddown, 0 hidden)
    + = Active Route, - = Last Active, * = Both

    1.1.1.0/30 *[Direct/0] 00:02:31
    > via xe-1/3/1.1
    1.1.1.2/32 *[Local/0] 00:02:31
    Local via xe-1/3/1.1
    192.168.1.100/32 *[OSPF/10] 00:01:39, metric 1   <<<< this is the local CE loopback leanred from OSPF

     

    labroot@rigel-re0# run show route advertising-protocol bgp 192.168.1.104 logical-system r1
    test.inet.0: 6 destinations, 8 routes (6 active, 0 holddown, 0 hidden)
    Prefix Nexthop MED Lclpref AS path
    * 1.1.1.0/30 Self 100 I
    * 192.168.1.100/32 Self 1 100 I   <<<<< getting advertised to RR

    PS: Please accept my response as solution if it answers you query, kudos are appreciated too!

    Thanks
    Vishal




  • 7.  RE: Routing between PE and CE

    Posted 03-08-2020 15:51

    Do you have links to any documentation related to this ?

    Seems this is different from Cisco.

     

    thanks !!



  • 8.  RE: Routing between PE and CE

     
    Posted 03-09-2020 13:57

    Hi gongyayu,

     

    Including the vrf-target statement in the configuration for a VRF target community causes default VRF import and export policies to be generated that accept and tag routes with the specified target community. By default, all routes in the bgp.l3vpn.0 routing table are exported to the IBGP peers

     

    https://www.juniper.net/documentation/en_US/junos/topics/topic-map/l3-vpns-distributing-routes.html

     

    In the example configuration that I had shared in my response you can check the policy that junos created upon vrf-target configuration. You can see there is no term matching any protocol.

    Config:

    set logical-systems r1 routing-instances test vrf-target target:100:111111
    set logical-systems r1 routing-instances test protocols ospf export mpbgp_to_ospf

    labroot@rigel-re0# run show policy logical-system r1 __vrf-export-test-internal__   < default export policy
    Policy __vrf-export-test-internal__:
    Term unnamed:
    then community + __vrf-community-test-common-internal__ [target:100:111111 ] accept

    labroot@rigel-re0# run show policy logical-system r1 mpbgp_to_ospf
    Policy mpbgp_to_ospf:
    Term unnamed:
    from proto BGP     < manually configured policy has the protocol
    then accept

    PS: If you found my response useful, kudos are appreciated.

    Thanks
    Vishal



  • 9.  RE: Routing between PE and CE

     
    Posted 03-08-2020 06:47
    10.10.10.0/24
    99.99.99.0/24
    99.99.99.99/32

    The above 3 prefixes look correct. They are local/direct routes on PE1.

     

    Who is owning 11.11.11.11/32? 



  • 10.  RE: Routing between PE and CE

    Posted 03-08-2020 08:29

    MX-CE1 owns 11.11.11.11.

     

    thanks for taking a look at it.



  • 11.  RE: Routing between PE and CE

     
    Posted 03-08-2020 08:40

    I see,

     

    You must have leaked the route via, though I don't remember seeing such behavior 🙂 

    set routing-instances CustA vrf-target import target:2000:2000
    set routing-instances CustA vrf-target export target:2000:2000

     

    If you want more controlable import/export, please sue vrf-import/vrf-export  



  • 12.  RE: Routing between PE and CE

    Posted 03-08-2020 16:01

    I can't find where I leak this.

     

    thanks !!



  • 13.  RE: Routing between PE and CE

    Posted 03-08-2020 16:11
    router bgp 65100
     bgp log-neighbor-changes
     no bgp default ipv4-unicast
     neighbor 4.4.4.4 remote-as 65100
     neighbor 4.4.4.4 update-source Loopback0
     !
     address-family ipv4
     exit-address-family
     !
     address-family vpnv4
      neighbor 4.4.4.4 activate
      neighbor 4.4.4.4 send-community both
     exit-address-family
     !
     address-family ipv4 vrf CustA
      redistribute eigrp 10
      red ospf 20
     exit-address-family
    

    I have redistribute ospf 20 in cisco configuration.  wondering no need for Junos ?