CCDP achieved!!!

ccdp_design_largeTo be honest, the Arch exam 642-874 is probably one of the easiest exams I have taken. It wasn’t as brutal as CCDA where you had to memorize a number of things which made the exam look like a marketing exam for Cisco in terms of familiarizing yourself with their products.

Maybe I get to say this because I am working for an ISP and most of the questions they ask were the technology that I work with on a day to day basis such as VRF, fibre, Nexus, data center design etc.

Funny story, I wasn’t supposed to take this exam until end of this month. But last week I was looking around the Pearsonvue website thinking of moving it further and noticed that the testing center where I am going to take the exam had an available slot the very next day.

Silly me, told myself “well this might just be a glitch, 1. They don’t usually have a schedule on a Monday, it is usually between tue to thur 2. There should be a 24 hour notice before you can cancel or book an exam. So I clicked around trying to book the exam the next day which I thought was impossible or I was expecting it would give an error message. Well it went through so I had to no choice but to sit the exam in less than 15hours. My mind went over drive trying to go through all of CBTNuggets vids.

Got to the testing center the next day. They told me that they normally don’t accept candidate on Mondays and they only opened that slot Sunday evening for an internal employee. No one expected that someone would be online the night before and actually book an exam.

So sat the exam, I thought the questions were surprisingly easy. I had to intentionally slow down because I don’t want to experience what happened with my BCNE exam where I received an email from Brocade questioning how I was able to finish the exam that quick with good results.

My Cisco certs are now extended for another fresh three years and I have totally no more excuse but to go after my CCIE number 🙂

VRF Lite for Dual ISP Gateway

vrflite

Scenario:

Branch office decided to have two internet connections, both getting private addresses. It is not for redundant purposes but they want to dedicate one link for DATA and other for Voice over IP. Both internet tails are ordered through the same carrier set to one to many. This means there is a single physical link onsite with 2 logically tagged tails or in Cisco’s terminology VLAN.

Office has an 1921 Cisco router onsite and due to budget constraints, cannot afford to by an extra gigabit WIC to run their VOIP vlan on.

For the purpose of this lab, we are going to have 4 VLANs. Two VLANs facing the carrier (WAN) and another pair of VLANs for the DATA and VOIP LAN network.

WAN VLANs

1023 DATA, 1024 VOIP

WAN IPs

1023 = 203.149.1.2/30, 1024 = 203.149.1.6/30

LAN VLANs

10 DATA, 20 VOIP

LAN IPs

10 = 192.168.10.0/24, 20 = 192.168.20.0/24

Challenge is you have only 2 ports on your Cisco 1921 WAN/LAN but need to run 2 networks which will have their own default gateway to the carrier. How do you solve this?

VRF Lite

Virtual Routing and Forwarding is a magical way of creating layer 3 instances on your router. Kinda like having virtual routers inside your single router. It is lite because there are no MPLS gypsy magic involvedJ

Format:

Ip vrf <vrf name>

!

int <int name>

ip vrf forwarding <vrf name>

ip add x.x.x.x x.x.x.x

!

Just remember to do the ”ip vrf forwarding” command first before putting in your ip address. Doing it the other way around, you’d lose your ip address because the moment you type that command it creates the instance within the interface and removing existing address.

ip vrf DATA
ip vrf VOIP
!
int g0/1
no shut
!
int g0/1.1023
encap dot1q 1023
desc WAN_DATA
ip vrf forwarding DATA
ip add 203.149.1.2 255.255.255.252
!
int g0/1.1024
encap dot1q 1024
desc WAN_VOIP
ip vrf forwarding VOIP
ip add 203.149.1.6 255.255.255.252
!
int g0/0
no shut
!
int g0/0.10
encap dot1q 10
desc LAN_DATA
ip vrf forwarding DATA
ip add 192.168.10.1 255.255.255.0
!
int g0/0.20
encap dot1q 20
desc LAN_VOIP
ip vrf forwarding VOIP
ip add 192.168.20.1 255.255.255.0
!
ip route vrf DATA 0.0.0.0 0.0.0.0 203.149.1.1 255.255.255.252 name DATA_GATEWAY
ip route vrf VOIP 0.0.0.0 0.0.0.0 203.149.1.5 255.255.255.252 name DATA_GATEWAY
!

You can verify that you are on the right track by doing a “sh ip route” and there should be nothing on your global routing table.

Each VRF instance would have its own routing table. So here are some helpful verification commands.

sh ip route vrf <vrf name>, so in this case it would be “sh ip route vrf DATA”
ping vrf <vrf name> x.x.x.x, ping vrf DATA 203.149.1.1
sh ip arp vrf <vrf name>, sh ip arp vrf DATA

an exam away from CCDP

I knew from the beginning it was going to lead into this. I wouldn’t be able to help myself have the patience while I study for the CCIE without being tempted to take another exam. Its been monsterously busy at work for the last couple of months. As they say, we’ve been hitting record breaking sales and provisioning.

This also means being involved in more projects beyond the regular stuff that I do. Really challenging to find time these days to study and focus on atleast a topic. So to get my rhythm going, I decided to book in to sit the ARCH exam to achieve my 2nd pro-level cert from Cisco, Cisco Certified Design Professional.

To be honest, I got motivated to study as well because Jeremy Cioara just released his latest training vids on Cisco ARCH. I would just go through his videos if I get the chance or while I drive on my way to work. So far, ARCH is just a review of CCDA going through an overview of different network technologies and how you can apply them in designing a good network. Hopefully unlike the CCDA I took, it wouldn’t test me much on a lot of unknown Cisco technologies or offering that I have no idea they exist to begin with.

If everything goes well, hopefully, I can take the exam by the end of the month.