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UPDATE on 2.11.2013 – There will be an update in February 2014!

Read all about the new announcement in the latest article here! with all new topics added and removed from CCIE lab exam v5.

UPDATE on 23.07.2013 – There will be not update this year to v5 at least not for now…

So, there are some news. The news is that at this moment, few weeks after Cisco Live in Orlando we can say that CCIE lab exam v5 update is not going to happen this year. I other words, for us studying for the lab exam, the old topology and all the topics from v4 are still valid. Many of us will think now that we can be in peace for another year now and try to learn and understand everything so that we can pass the exam before the change. From my perspective, maybe this is not the whole truth. I think that even the change in the exam and all the topics mentioned down here that would change will not necessary mean that the exam would become more difficult. My perspective is that if you are prepared to pass the CCIE lab on v4, you will be probably also prepared to pass it on v5. My point is in that there is so many networking topics covered here that all the changes would not disturb you in your goal, maybe only those people who studied but not really with 100% understanding. The road to CCIE is not short, and is not easy either but it can be fun and in the end it will be worth the effort.

Learn and enjoy the process to, not only thinking on the resulting cert. In that way, you will probably be more succesful even in the CCIE lab changes a bit.

Policy-Based Routing Configuration

Here we will show different examples on how to configure specific PBR types:

• Enabling PBR on the Router
• Fast-Switched PBR
• Local PBR
• CEF-Switched PBR

Enabling PBR

This command will define that the router will use PBR and that the PBR will use route-map named TEST.

R1(config)# route-map TEST permit 10

About Policy-Based Routing

Policy-Based Routing – PBR gives you very simple way of controlling where packets will be forwarded before they enter in the destination-based routing process of the router.

It’s a technology that gives you more control over network traffic flow because you will not always want to send certain packets by the obvious shortest path. That is the job of routing protocol. If you want to send some traffic to the destination using some other path, you will need to use a method that will catch the packet as soon as they enter into router and decides where to send packets before they enter destination-based routing process. That’s Policy-Based routing all about.

What is Wildcard Masking?

Wildcard mask is like any other computer IP address basically a group od zeroes and ones (o and 1). To be short, in wildcard mask all number one (1) mean “I don’t care about that position”, and all zeroes (0) mean “I care about that position in binary address”. Let’s take an example where Access list with wildcardmask will be able to deny fourth subnet and alow next four and so on for all /24 subnets of 192.168.0.0/16 supernetwork.

In the access-list we put an  0.0.0.0 255.255.251.255 network;

We know that 255 means 1111 1111 in binary.
We know that 251 means 1111 1011 in binary.

In the 0.0.0.0 255.255.251.255 line we could change 0.0.0.0 to any other kind of 1.1.0.1 23.23.0.33 because in this situation our ACL will not care about the bits in the first, second and last octet. We could write 192.168.0.0 it will fit in our example.

One more thing to make myself more clear. If we use deny 192.168.0.0 255.255.251.255 in ACL, this ACL will not filter only 192.168.0.0/16 network, but every network in the whole 32bit range from 0.0.0.0 to 255.255.255.255 in which third octet has an zero (0) in 6th position. To filter only those subnets that are part of 192.168.0.0/16 supernet we would need to use deny 192.168.0.0 0.0.251.255 because in that way we will say that we care about first and second octet of the address.

Example: