[j-nsp] JNCIP question: eBGP policy

[Chris Grundemann]

Hi Min,

For the test, I would recommend that you do not assume anything
specific ahead of time.  As you stated in your first question, "even
if it's real world, [you] have to follow what's required."

The requirements given on the test will be similar to those given in
the case studies and in some cases may be the same but there is no
point to memorizing the specific policy chains nor individual policies
since you don't know what the specific combination of requirements
will be on the exam.

My best advice is to make sure that you understand how to meet the
various requirements with policy so that yo are prepared for anything,
rather than trying to anticipate the requirements.  More specific
advice below:

On Tue, Sep 1, 2009 at 16:03, Min<smartsuites at gmail.com> wrote:
> hey guys, I have a few reqestions during studying JNCIP book. hopefull
> someone can help here.
>
> 1. Can I safely assume and configure following annoucing policy since
> it's the way in the real world:
>    " send cust routes to transit and peer, send peer routes to cust,
> sent transit routes to cust. "
>
> I noticed sometimes JNCIP question doesn't require one or some of
> them, is it ok for me to implement all? sometimes it's required that
> "send peer routes to transit", I know even it's not in real world, I
> have to follow what required.

The most important thing is to make sure that you read and understand
the provided requirements and restrictions regarding what routes to
announce to whom.  In order to fully test your knowledge, the tests
requirements (in my experience) often did not follow a real-world
scenario.  Typically, anything that is not specifically forbidden is
allowed but you have to take into consideration all of the affects if
you are going to do something not specifically required as it may
impact routing in a way that interferes with a separate requirement or
restriction.

>
> 2. in practice, we normally define eBGP import policy like this:
> [ generic-filter-in generic-community-setup community-setup-as65050
> prefer-peer ]
>
> generic-filter-in and generic-community shared by all ebgp import
> policy on this router; prefer-peer shared by all peer ebgp import
> policy, community-setup-as65050 tags peer specific community.
>
> with extra requirement for some peers, one or some of these policy [
> as65050-filter-in no-comms damping prepend-twice ] will be added to
> policy chain.
>
> I'm wondering if this is a good policy formation for JNCIP test?

Again, it is going to depend on the specific requirements and
restrictions provided on the day of your exam -- focus on
understanding how to implement various requirements with policy,
rather than what the requirements should be.

>
> Min

Hope that is helpful even if it is not exactly the answer you were
looking for.  For a bit more information on the IP exam in general,
you may want to look over my recent post: JNCIP-M Lab Exam Q&A
(http://weblog.chrisgrundemann.com/index.php/2009/jncip-lab-exam-faq/).

~Chris


> _______________________________________________
> juniper-nsp mailing list juniper-nsp at puck.nether.net
> https://puck.nether.net/mailman/listinfo/juniper-nsp
>


-- 
Chris Grundemann
weblog.chrisgrundemann.com
www.burningwiththebush.com
www.coisoc.org