Redundant Routes, BGP with MPLS provider

Bill.Ingrum at t-systems.com Bill.Ingrum at t-systems.com
Fri Aug 31 11:33:45 CDT 2012


I work for an MPLS provider, so I guess I tend to trust them ;)

Bill

-----Original Message-----
From: Lee [mailto:ler762 at gmail.com] 
Sent: Friday, August 31, 2012 11:28 AM
To: Ingrum, Bill
Cc: WTribble at sterneagee.com; nanog at nanog.org
Subject: Re: Redundant Routes, BGP with MPLS provider

On 8/31/12, Bill.Ingrum at t-systems.com <Bill.Ingrum at t-systems.com> wrote:
> I think having a GRE tunnel for the internal routing protocol is 
> unnecessary.

It might be, but we have a requirement for multicast over the wan so the
GRE tunnels had to be there.

>  Can you explain the reasoning behind this?  I understand the 
> technical issue whereby GRE will allow multicast for EIGRP, OSPF, etc,

> but why not just redistribute into BGP?

I see no reason to trust the provider that much.

> I work on a lot of MPLS CE routers, and in general you can accomplish 
> anything you need by redistributing your internal routing protocol 
> into BGP, and adjusting LP, MED and AS Prepend as needed.

Sure.. but how do you *know* you're not getting anything added/removed
by the provider?

Lee



>
> Thanks,
>
> Bill
>
> -----Original Message-----
> From: Lee [mailto:ler762 at gmail.com]
> Sent: Friday, August 31, 2012 11:15 AM
> To: Tribble, Wesley
> Cc: nanog at nanog.org
> Subject: Re: Redundant Routes, BGP with MPLS provider
>
> On 8/30/12, Tribble, Wesley <WTribble at sterneagee.com> wrote:
>> Hello all,
>>
>> I am an Network Operator working in an Enterprise environment with 
>> offices all over the country(mostly connected via MPLS).  We are 
>> currently working towards building a Disaster Recovery Site that will

>> host some of our vendor routers and provide the capability to access 
>> these vendors from both our primary and backup data center locations.
>
>> The routes(as advertised by the vendor's routers) will be the same at

>> both locations.  I would like to advertise the routes from multiple 
>> locations at the same time, rather than suppress the routes and
> advertise conditionally.
>
> At work, we have our internal routing protocol running on GRE over 
> IPSec tunnels & keep the BGP sessions with the MPLS provider limited 
> to just the MPLS network.  And have an ACL on the MPLS network
> interface that allows only what's expected in...   some providers are
> better than others at not having anything hit the 'deny any any log'
> line
>
> Regards,
> Lee
>
>
>>
>> What is the best method to Instruct the provider's network to prefer 
>> the Primary Data Center routes over the DR site?  Keep in mind that I

>> am only peering with the provider over BGP and I have no visibility 
>> to
>
>> the underlying MPLS architecture or configuration.  Although if you 
>> have specific questions  about their architecture, I can work to get
> answers.
>>
>> Discussing in house, we have gone over a few different options:
>>
>> -Advertise specific routes from primary site and summary routes from 
>> the DR site.  Most specific will always be chosen.
>> -Prepend the routes from the DR site so that they will have a longer 
>> AS-path than the Primary location -Use Community Strings to influence

>> local preference.(Still working to find out if Provider will pass our

>> community strings)
>>
>> Just looking for some ideas and best practices.  Any thoughts or 
>> insight would be much welcomed and appreciated.  This is my first 
>> message on NANOG, so please be gentle.  I apologize in advance if I 
>> have done something incorrectly.
>>
>>
>> Wes
>>
>>
>> ________________________________
>> *********************************************************************
>> *
>> **************************** Sterne Agee Group, Inc. and its 
>> subsidiaries request that you do not transmit orders and instructions

>> regarding your Sterne Agee account by e-mail. Transactional details 
>> do
>
>> not supersede normal trade confirmations or statements. The 
>> information contained in this transmission is privileged and 
>> confidential. It is intended for the use of the individual or entity 
>> named above. The information contained herein is based on sources we 
>> believe reliable but is not considered all-inclusive. Opinions are 
>> our
>
>> current opinions only and are subject to change without notice.
>> Offerings are subject to prior sale and/or change in price. Prices, 
>> quotes, rates and yields are subject to change without notice. Sterne

>> Agee & Leach, Inc. member FINRA and SIPC, is a registered 
>> broker-dealer subsidiary of Sterne Agee Group, Inc. Generally, 
>> investments are NOT FDIC INSURED, NOT BANK GUARANTEED, and MAY LOSE 
>> VALUE. Please contact your Financial Advisor with information 
>> regarding specific investments.
>> Sterne Agee
>> reserves the right to monitor all electronic correspondence.
>>
> **********************************************************************
> **
> **************************
>>
>
>



More information about the NANOG mailing list