How to turn a standard BGP into a MP-BGP?

[rookie R]

Hi everyone!

As far as I know, the Multiprotocol BGP can support multiple address-family, while the standard BGP can only support ipv4 address. However, I am not sure how to determine if a BGP is standard that can only support ipv4 or MP-BGP that can support multiple address, and how to convert standard BGP to MP-BGP.

I know that the

no bgp default ipv4 unicast

 command can only turn off the default behavior that puts all the neighbors into the ipv4 unicast address family. It's not the switch to convert standard BGP into mp-bgp, so what is that switch to enable MP-BGP?

I searched on the internet and found a Juniper document that said:

Sorry, I couldn't find any Cisco document about this due to my poor ability, so I posted this Juniper document here.

So, is this the same in Cisco devices? Is it the same to assume that there is another address-family other than ipv4 unicast(for example, ipv6 unicast or ipv4 multicast), then it is MP-BGP? And If there is only ipv4 unicast in the configuration, then it's a standard BGP even if there is

no bgp default ipv4 unicast

command there?

R5(config)#do show run | s r b
router bgp 10005
bgp router-id 5.5.5.5
bgp log-neighbor-changes
no bgp default ipv4-unicast
neighbor 192.168.45.4 remote-as 10004

The above one is standard BGP, right?

R5(config-router-af)#do show run | s r b
router bgp 10005
bgp router-id 5.5.5.5
bgp log-neighbor-changes
no bgp default ipv4-unicast
neighbor 192.168.45.4 remote-as 10004
!
address-family ipv6
exit-address-family

The second one is MP-BGP,right?

Thank you!

[Gopinath_Pigili]

Hello rookie R,

• MP-BGP is an extended BGP that allows BGP to carry routing information for multiple network layer protocols IPv6, VPNv4, and others. MP-BGP allows you to have a unicast routing topology different from a multicast routing topology, which helps to control the network and resources.
• By default, commands entered under the 

  router bgp 

• command apply to the IPv4 address family. This will continue to be the case unless you enter the 

  no bgp default ipv4-unicast 

• command as the first command under the 

  router bgp 

• command. The 

  no bgp default ipv4-unicast

•  command is configured on the router to disable the default behavior of the BGP routing process exchanging only IPv4 addressing information with BGP neighbor routers. Now, BGP routing process can exchange IPv4, IPv6 and VPNv4 addressing information with BGP neighbors.
• Cisco IOS version 12.4T or Later versions supports MP-BGP

Reference: Encor official Cert Guide; https://www.cisco.com/c/en/us/support/docs/ip/border-gateway-protocol-bgp/113555-mp-ebgp-config-00.html

Best regards
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[M02@rt37 · Accepted solution]

Hello @rookie R 

To enable MP-BGP, you need to introduce other address families beyond IPv4 unicast.

MP-BGP support multiple address families. The presence of other address families indicates the use of MP-BGP.

** MP-BGP is specified in RFC 2283.

http://www.ietf.org/rfc/rfc2283.txt?number=2283

[paul driver]

Hello

You can use the

bgp upgrade-cli

command to convert BGP into the Address Family (AF) format or manually configure an AF  within the bgp process which will then change bgp to the AF format.

router bgp xx
bgp upgrade-cli

or 
router bgp xx
address-family ipv4 unicast|multicast
address-family ipv4 vrf (vrf)
address-family ....etc

[MHM Cisco World]

I think all new IOS ver. is run MP-BGP 
https://aurumme.com/atech/mp-bgp-address-families/

MHM

[MHM Cisco World]

again all new IOS is run MP-BGP (extension of BGP-4)
so your original post is MP-BGP and you config IPv4 under it.
MHM