Re: ISIS L1 vs L2

I agree with this statement completely.

Paul Negron
CCIE# 14856
negron.paul_at_gmail.com
303-725-8162

On Nov 28, 2012, at 8:56 AM, shiran guez <shiranp3_at_gmail.com> wrote:

> L1/L2 everywhere is not making much sense as you will
> have redundant database for both L1 and L2. normally Core you will work L2
> edge to "stub" you will do L1/L2 and stub networks you will set L1, L2 will
> provide you future flexibility, even if you think that you will not expand
> or change, it is not a good design to do a limit yourself from the start,
> it does not cost anything to do it L2, but it will cost plenty if you will
> need to change Core in future.
>
> my 2 cents :-)
>
>
> On Wed, Nov 28, 2012 at 3:18 PM, Ronnie Angello
<ronnie.angello_at_gmail.com>wrote:
>
>> A single L1/L2 domain would be best as it provides flexibility... That
>> way you already have a contiguous L2 domain. If the network grows, it's
>> easier to add an L1 routing domain than it is to add an L2 routing domain.
>> You just add an L1 IS to the edge and push the L1 domain into the
network...
>>
>> Ronnie
>>
>> Sent from my iPhone
>>
>> On Nov 27, 2012, at 10:24 PM, Routing Freak <routingfreak_at_gmail.com>
>> wrote:
>>
>>> Hi all
>>>
>>> In my customer core network where we had a heated about wither OSPF or
>> ISIS
>>> and finally ISIS won the race for the core IGP due to some business
>>> decision and now my problem here is that when i was designing the network
>>> with one large ISIS area with all the linka s L1, everyone opposed me to
>>> not to configure L1 and go for L2.
>>>
>>> I know that L1 is within single area and L2 can be connected across areas
>>> and also within a single area and it carries all the routes within L1 and
>>> L2.
>>>
>>> But in my design , i have single large area with all links as L1, what is
>>> the problem in that, L1 or L2 it should be the same.
>>>
>>> I didnt understood what is the logic behind the fact that L1 should not
>> be
>>> used and L2 should be used.
>>>
>>> I thought may be when they are forming more areas, then l2 makes sense,
>> but
>>> they r not going to expand the site with another area, so why not going
>> for
>>> L1 will suffice the requirement .
>>>
>>> L1 is within one single area and doesnt know any other routes of other
>> area
>>>
>>> L2 router is one where all the areas merge and exchange routes in one
>>> separate area. It can be any area and not area 0 and just all the routers
>>> in that particular area should be running L2 adjacency with each other.
>>>
>>>
>>> In one large area, which is better L1 or L2. Any ISIS Experts, be sure to
>>> reply to this.
>>>
>>>
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>>
>>
>>
>>
>
>
> --
> Shiran Guez
> MCSE CCNP NCE1 JNCIA-ENT JNCIS-ENT CCIE #20572
> http://cciep3.blogspot.com
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Received on Wed Nov 28 2012 - 16:37:47 ART