Interesting. I was also pretty sure that didn't work. At best it would
only do a passive open (respond to a TCP syn) no originate the
session.

Bob
-- 
Sent from my iPhone, please excuse any typos.

On Oct 11, 2012, at 8:25 AM, Nick Bonifacio <[email protected]> wrote:

> //Disclaimer:  I am using GNS3 for this example.
>
> This is the way I understand it, anyone else feel free to chime in:
>
> Think update source.
>
> router bgp 4
> neighbor 10.0.4.5 remote-as 5
> neighbor 10.0.4.5 update-source FastEthernet0/0
>
>
> interface FastEthernet0/0
>  ip address 10.0.4.4 255.255.255.0
>  duplex auto
>  speed auto
>  standby 0 ip 10.0.4.254
>
> how can I create a neighborship by sourcing the standby 0 IP?  I can't.
>
> Let's look at router 5 on the other side
>
> interface FastEthernet0/0
>  ip address 10.0.4.5 255.255.255.0
>  duplex auto
>  speed auto
>
> router bgp 5
>  no synchronization
>  bgp log-neighbor-changes
>  neighbor 10.0.1.1 remote-as 1
>  neighbor 10.0.4.254 remote-as 4
>  no auto-summary
>
>
> Let's debug BGP on R4
>
> R4(config-router)#no
> *Mar  1 00:31:36.267: BGP: 10.0.4.5 passive open to 10.0.4.254
> *Mar  1 00:31:36.271: BGP: 10.0.4.5 passive open failed - 10.0.4.254 is not 
> update-source FastEthernet0/0's address (10.0.4.4)
> *Mar  1 00:31:36.271: BGP: 10.0.4.5 remote connection attempt failed, local 
> address 10.0.4.254
> R4(config-router)#no
> *Mar  1 00:31:38.255: BGP: 10.0.4.5 open active, local address 10.0.4.4
> *Mar  1 00:31:38.311: BGP: 10.0.4.5 open failed: Connection refused by remote 
> host, open active delayed 26388ms (35000ms max, 28% jitter)
> R4(config-router)#no
>
> ok it is complaining about 10.0.4.254 not being fa0/0's address.  Fine, I 
> will remove update source fa0/0
>
>
>
> router bgp 4
>  no synchronization
>  bgp log-neighbor-changes
>  neighbor 10.0.4.2 remote-as 2
>  neighbor 10.0.4.3 remote-as 3
>  neighbor 10.0.4.5 remote-as 5
>  neighbor 10.0.4.5 update-source FastEthernet0/0
>  maximum-paths 3
>  no auto-summary
>
> no neighbor 10.0.4.5 update-source FastEthernet0/0
>
> BGP: 10.0.4.5 rcvd OPEN w/ remote AS 5
> *Mar  1 00:33:09.427: BGP: 10.0.4.5 went from OpenSent to OpenConfirm
> *Mar  1 00:33:09.427: BGP: 10.0.4.5 send message type 1, length (incl. 
> header) 45
> *Mar  1 00:33:09.475: BGP: 10.0.4.5 went from OpenConfirm to Established
> *Mar  1 00:33:09.475: %BGP-5-ADJCHANGE: neighbor 10.0.4.5 Up
>
> uh oh, it is working!  Interesting.. I am in GNS3 but will lab it up at home 
> on real hardware once I get there.  This is not the behavior I expected.
>
> R5#sh ip bgp sum
> [...]
> Neighbor        V    AS MsgRcvd MsgSent   TblVer  InQ OutQ Up/Down  
> State/PfxRcd
> 10.0.1.1        4     1      40      40        2    0    0 00:36:01        1
> 10.0.4.254      4     4      16      22        2    0    0 00:02:47        1
>
>
> I also tested it with iBGP and the same behavior occured.  I also failed over 
> the HSRP address and made another node active as 10.0.4.254 and the adjacency 
> did come back up on that router!
>
> I will try this out on real hardware once I get home and then report back.  
> We had tried this in production 2 months ago using ASR1000s and could not get 
> it working.
>
> Nick
>
>
> ________________________________
> From: Samir Idris <[email protected]>
> To: Nick Bonifacio <[email protected]>
> Cc: Taqdir Singh <[email protected]>; "[email protected]" 
> <[email protected]>
> Sent: Thursday, October 11, 2012 7:50 AM
> Subject: Re: [OSL | CCIE_RS] Hello team can we make bgp neighbor ship HSRP 
> virtual IP ?
>
>
> Nick,
>
> Why cant we source from a virtual IP?  Can you shed some light on the logic?
>
> Regards,
> Samir.
>
> On Thursday, October 11, 2012, Nick Bonifacio <[email protected]> wrote:
>> Hi Taqdir,
>>
>> You have to source from a physical interface and cannot source from a vIP.  
>> Here is a link to "best practice" using HSRP and multihomed BGP environments:
>>
>> http://www.cisco.com/en/US/tech/tk365/technologies_configuration_example09186a0080093f2c.shtml
>>
>>
>> Thanks!
>> Nick
>>
>> ________________________________
>>  From: Taqdir Singh <[email protected]>
>> To: [email protected]
>> Sent: Thursday, October 11, 2012 3:16 AM
>> Subject: [OSL | CCIE_RS] Hello team can we make bgp neighbor ship HSRP 
>> virtual IP ?
>>
>> Hello team can we make bgp neighborship with HSRP virtual IP ?
>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, please 
>> visit http://www.ipexpert.com/
>>
>> Are you a CCNP or CCIE and looking for a job? Check out 
>> http://www.platinumplacement.com/
>>
>> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>> _______________________________________________
>> For more information regarding industry leading CCIE Lab training, please 
>> visit http://www.ipexpert.com/
>>
>> Are you a CCNP or CCIE and looking for a job? Check out 
>> http://www.platinumplacement.com/
>>
>> http://onlinestudylist.com/mailman/listinfo/ccie_rs
>
> --
> Samir Idris
> _______________________________________________
> For more information regarding industry leading CCIE Lab training, please 
> visit www.ipexpert.com
>
> Are you a CCNP or CCIE and looking for a job? Check out 
> www.PlatinumPlacement.com
>
> http://onlinestudylist.com/mailman/listinfo/ccie_rs
_______________________________________________
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