Routing
Routing

Virtual router multiple ASN and BGP session on single device

‎03-10-2018 10:18 AM

Hello,

Can anyone explain how virtual router works on Junos?

Say Ex4200 configured with ASN1  and peer with  AS100

Now AS2, AS3 and AS4 are configured on EX4200 and peer with ASN1 running default route so it looks like

 

AS1 >>>>>AS100

AS2 >>> AS1 >>> AS100

AS3 >>> AS1 >>> AS100
AS4 >>> AS1 >>> AS100

I understand there is virtual router option where we can define VRF's but how to peer and setup BGP session with  each other?

Thanks in advance.

6 REPLIES 6
Routing

Re: Virtual router multiple ASN and BGP session on single device

[ Edited ]
‎03-11-2018 12:23 AM

Hi metallica,

 

If i understand your question correctly. you would like to configure the BGP between the Virtual Routers(VR)

1. My example i have xe-2/0/2 is on VR(CUSTA) and xe-2/0/3 on VR(CUSTB)
2. Both configured with vitual router instance and bgp is configured

Configuratin:

CUSA {
instance-type virtual-router;
interface xe-2/0/3.0;
protocols {
bgp {
group ebgp {
neighbor 5.0.0.1 {
peer-as 1;
local-as 100;
}
}
}
}
}
CUSB {
instance-type virtual-router;
interface xe-2/0/2.0;
protocols {
bgp {
group ebgp {
neighbor 5.0.0.2 {
peer-as 100;
local-as 1;
}
}
}
}
}

 

# run show bgp summary instance CUSA
Groups: 1 Peers: 1 Down peers: 0
Table Tot Paths Act Paths Suppressed History Damp State Pending
CUSA.inet.0
0 0 0 0 0 0
CUSA.mdt.0
0 0 0 0 0 0
Peer AS InPkt OutPkt OutQ Flaps Last Up/Dwn State|#Active/Received/Accepted/Damped...
5.0.0.1 1 7 8 0 0 2:34 Establ
CUSA.inet.0: 0/0/0/0

 

# run show bgp summary instance CUSB
Groups: 1 Peers: 1 Down peers: 0
Table Tot Paths Act Paths Suppressed History Damp State Pending
CUSB.inet.0
0 0 0 0 0 0
CUSB.mdt.0
0 0 0 0 0 0
Peer AS InPkt OutPkt OutQ Flaps Last Up/Dwn State|#Active/Received/Accepted/Damped...
5.0.0.2 100 8 8 0 0 2:36 Establ
CUSB.inet.0: 0/0/0/0

 

  

Hope this helps

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Routing

Re: Virtual router multiple ASN and BGP session on single device

‎03-11-2018 12:40 AM

Instead of virtual-router, you should configure logical-system, were the control-plane is separated between the nodes(LS):

 

https://www.juniper.net/documentation/en_US/junos/topics/concept/logical-systems-overview-solutions....

https://forums.juniper.net/t5/Routing/How-To-Build-a-service-provider-network-with-a-single-Juniper/...

 

/Karan Dhanak
# Please mark my solution as accepted if it helped, Kudos are appreciated as well.

Routing

Re: Virtual router multiple ASN and BGP session on single device

‎03-11-2018 06:01 AM

Hello,

Two things to be aware of:

1/ EX-series do not support Logical Systems

2/ if all of the OP ASNs (1,2,3,4,100) are configured on a single device, then JUNOS by default does loop checking for ALL LOCALLY-CONFIGURED AS numbers. This can be circumvented by either "autonomous-system loops $count", "loops $count" under "protocols bgp ... family inet unicast", or "routing-options independent-domain" but EX-series do not appear to support "independent-domain"

https://www.juniper.net/documentation/en_US/junos/topics/reference/configuration-statement/independe...

Supported Platforms

HTH

Thx
Alex

 

_____________________________________________________________________

Please ask Your Juniper account team about Juniper Professional Services offerings.
Juniper PS can design, test & build the network/part of the network as per Your requirements

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Routing

Re: Virtual router multiple ASN and BGP session on single device

‎03-11-2018 06:35 AM

 

LS is supported on EX-Series.

 

/Karan Dhanak
# Please mark my solution as accepted if it helped, Kudos are appreciated as well.

Routing

Re: Virtual router multiple ASN and BGP session on single device

‎03-11-2018 08:57 AM

 

 

Hi metallica,

 

You can try Logical system or Virtual router. 

 

Using Virtual router instance, we are Splitting a device into many virtual routing instances isolates traffic traveling across the network without requiring multiple devices to segment the network Logical system.

 

Its upto your choice

 

Virtual router:

 

https://www.juniper.net/documentation/en_US/junos/topics/concept/bridging-vrf-ex-series.html

Supported Platforms

 

Logical system:

 

https://www.juniper.net/documentation/en_US/junos/topics/concept/logical-systems-restrictions.html

 

Supported Platforms

 

Hope this helps

-----------------------------------------------------------------------------------------------
If this post was helpful, please mark this post as an "Accepted Solution".
Kudos are always appreciated!
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Routing

Re: Virtual router multiple ASN and BGP session on single device

‎03-11-2018 10:36 AM

Hello,


@karand wrote:

 

LS is supported on EX-Series.

 


Yeah, should have been more specific - they are supported on EX9200 only. LS are not supported on EX4200.

HTH

Thx

Alex

_____________________________________________________________________

Please ask Your Juniper account team about Juniper Professional Services offerings.
Juniper PS can design, test & build the network/part of the network as per Your requirements

+++++++++++++++++++++++++++++++++++++++++++++

Accept as Solution = cool !
Accept as Solution+Kudo = You are a Star !