Re: OT: GS Archives Search

hahahahahaha

I thought it all happens automagically.

On Tue, Mar 27, 2012 at 8:34 AM, Brian McGahan <bmcgahan_at_ine.com> wrote:

> > The "Route-target" is a BGP extended community that indicates which
> routes should be exported from a given VRF or imported into a given VRF.
>
> The Route Target doesn't control which routes leave the VRF to go into
> VPNv4 BGP, redistribution controls this. If you don't set a Route Target
> the VPNv4 routes will still originated, but no one will be able to import
> them on the other side. This is actually a common misconfiguration for
> MPLS L3VPN.
>
> Brian McGahan, CCIE #8593 (R&S/SP/Security)
> bmcgahan_at_INE.com
>
> Internetwork Expert, Inc.
> http://www.INE.com
>
>
> From: Narbik Kocharians [mailto:narbikk_at_gmail.com]
> Sent: Monday, March 26, 2012 9:18 PM
> To: Brian McGahan
> Cc: Marko Milivojevic; Yemi Salau; ccielab_at_groupstudy.com
> Subject: Re: OT: GS Archives Search
>
> Since we all know what VRFs are. Remember that the VRF is NOT operational
> without an RD.
> What is an RD? An RD is a 64 bit value that is attached to the customer's
> IPv4 address, to make it a Unique 96 bit address called VPNv4. These
> addresses are ONLY exchanged between the PE routers. In Brian's example,
> RDs distinguish one route from another, in his example 10.0.0.0:A from
> 10.0.0.0:B.
>
> I think that the name "VPNv4" is the worst name they could assign to these
> addresses, because many people think that RDs define the VPN, and they DO
> NOT define the VPN.
>
> Once the PE router attaches the RD to the CE routes, it then sends the
> VPNv4 address/es to the other PE router/s. The receiving PE router strips
> the RD from the VPNv4 prefix, and it's left with an IPv4 address.
>
> NOW..How does the receiving PE know which VRF does the IP address belong
> to? The answer is "Route-Target".
>
> The "Route-target" is a BGP extended community that indicates which routes
> should be exported from a given VRF or imported into a given VRF.
> I hope this helped.
> On Mon, Mar 26, 2012 at 6:27 PM, Brian McGahan <bmcgahan_at_ine.com> wrote:
> Personally that seems overly confusing to me. Yes Route Targets are an
> attribute of the route, but that attribute is not part of the BGP Bestpath
> Selection. I'm not sure how it ties together. It's simpler to think of it
> this way:
>
> It's given that customers of a Service Provider will have overlapping IP
> addressing in their VPNs, e.g. you will have more than two customers who
> use the 10.0.0.0/8 network. The RD is how you tell them apart. If you
> have customer "A" with RD "A" and customer "B" with RD "B" the routes "A:
> 10.0.0.0/8" and "B:10.0.0.0/8" become unique. This is all the RD does.
>
> The Route Target tells you which VRF table the route belongs to. You have
> to separate the two attributes because sometimes you want the same route to
> belong to multiple VRF tables. This is common in what's known as "Central
> Services VPNs". For example if the Service Provider hosts email for
> customers, that route to the mail server would have to be in the routing
> table of multiple customers. This doesn't break the rule of the route
> having to be unique though, which is what the RD does.
>
> Like I said you may be able to find more clarification in this video:
> http://goo.gl/Y0imB.
>
> Brian McGahan, CCIE #8593 (R&S/SP/Security)
> bmcgahan_at_INE.com
>
> Internetwork Expert, Inc.
> http://www.INE.com
>
> -----Original Message-----
> From: nobody_at_groupstudy.com [mailto:nobody_at_groupstudy.com] On Behalf Of
> Marko Milivojevic
> Sent: Monday, March 26, 2012 6:00 PM
> To: Yemi Salau
> Cc: ccielab_at_groupstudy.com
> Subject: Re: OT: GS Archives Search
>
> Simple reason - prefixes are passed on through the bestpath selection
> process where the best one is chosen based on attributes. RT is a
> community, which is an attribute. This means that given two prefixes with
> different RTs would be treated as equals when it comes to bestpath
> selection. With RD we extend the prefix space to 86 bits and then use those
> for comparison instead of 32bit ones.
>
> [ iPhone, brevity, etc disclaimer :-) ]
>
> --
> Marko Milivojevic - CCIE #18427
>
> :: This message was sent from a mobile device. I apologize for errors and
> brevity. ::
>
> On Mar 26, 2012, at 14:44, Yemi Salau <salauolayemi_at_yahoo.co.uk> wrote:
>
> > Thanks Marko, reading RFC 4364, I was trying to figure out why RT
> > couldn't
> do the same job of RD for uniquely separating VPN-IPv4 routes within the
> provider MPLS cloud. I'll watch your video when I get home. Many Thanks.
> >
> > From: Marko Milivojevic <markom_at_ipexpert.com>
> > To: Yemi Salau <salauolayemi_at_yahoo.co.uk>
> > Cc: ccielab_at_groupstudy.com
> > Sent: Monday, 26 March 2012, 16:25
> > Subject: Re: OT: GS Archives Search
> >
> >
> > Yemi,
> >
> > I'm not sure about the Archive search, but I can certainly help you
> > with RD
> and RT. Almost two years ago I hosted a free online training session
> called "MPLS 101". You can find it, together with all other recorded
> vLectures on many other subjects here:
> >
> > http://bit.ly/vLecture
> >
> > Please go ahead and watch it and if you have any questions feel free
> > to ask
> them here.
> >
> > --
> > Marko Milivojevic - CCIE #18427 (SP R&S) Senior CCIE Instructor -
> > IPexpert
> >
> > On Mon, Mar 26, 2012 at 10:18, Yemi Salau <salauolayemi_at_yahoo.co.uk>
> wrote:
> > Guys,
> >
> > I remember a time where I was able to search the GS archives for
> > stuffs. Is
> this still available today? I want to search out some stuffs on RD vs RT.
> >
> > Yemi
> >
> >
> > Blogs and organic groups at http://www.ccie.net
> >
> > ______________________________________________________________________
> > _ Subscription information may be found at:
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>
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> _______________________________________________________________________
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>
>
>
>
>
>
>
>
> --
> Narbik Kocharians
> CCSI#30832, CCIE# 12410 (R&S, SP, Security)
> www.MicronicsTraining.com
> Sr. Technical Instructor
> YES! We take Cisco Learning Credits!
> A Cisco Learning Partner
>
>

-- 
*Narbik Kocharians
*CCSI#30832, CCIE# 12410 (R&S, SP, Security)
*www.MicronicsTraining.com* <http://www.micronicstraining.com/>
Sr. Technical Instructor
YES! We take Cisco Learning Credits!
A Cisco Learning Partner
Blogs and organic groups at http://www.ccie.net