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If there’s one CCNP / BSCI topic that looks so easy but can lead to a real headache, it’s route redistribution. I’m not even talking about the routing loops and suboptimal routing that can result when route redistribution is done without proper planning – I’m talking about the basic commands themselves. Leaving out one single command option, or forgetting what else needs to be redistributed when redistributing dynamically discovered routes, can leave you with a routing table that looks complete but does not result in full IP connectivity.

In this free CCNP / BSCI tutorial series, we’ll take a look at three common errors in route redistribution configurations, and how to fix them. We’ll use three routers, R1, R3, and R5. R1 and R5 are in a RIPv2 domain and R1 and R3 are in an OSPF domain. R1 will be performing two-way route redistribution.

R5 is advertising its loopback, 5.5.5.5/24, into the RIPv2 domain. R1 sees this route in its RIP routing table:

R1#show ip route rip

5.0.0.0/24 is subnetted, 1 subnets

R 5.5.5.0 [120/1] via 100.1.1.5, 00:00:01, Ethernet0

For R3 to see this route, route redistribution must be configured on R1. We’ll use the redistribute rip command to do so.

R1(config)#router ospf 1

R1(config-router)#redistribute rip

% Only classful networks will be redistributed

The router immediately gives us a message that “only classful networks will be redistributed”. What does this mean? Let’s go to R3 and see if that router is receiving this route.

R3#show ip route ospf

< no output >

When we get no result from a show command, that means there’s nothing to show. The only routes that will be successfully redistributed with the current configuration on R1 are classful networks, and 5.5.5.0/24 is a subnet.

To further illustrate the point, a classful network has been added to R5. This network is 16.0.0.0 /8, and is now being advertised by RIP. R1 sees this network as classful…

R1#show ip route rip

R 16.0.0.0/8 [120/1] via 100.1.1.5, 00:00:00, Ethernet0

5.0.0.0/24 is subnetted, 1 subnets

R 5.5.5.0 [120/1] via 100.1.1.5, 00:00:00, Ethernet0

… and R3 is receiving the route through redistribution.

R3#show ip route ospf

O E2 16.0.0.0/8 [110/20] via 172.12.123.1, 00:00:08, Serial0.31

To redistribute both classful and classless networks, the option “subnets” must be added to the redistribute command on R1.

R1(config)#router ospf 1

R1(config-router)#no redistribute rip

R1(config-router)#redistribute rip subnets

R3 will now see both the classful and classless networks being redistributed into OSPF. (100.1.1.0 is the network connecting R1 and R5.)

R3#show ip route ospf

O E2 16.0.0.0/8 [110/20] via 172.12.123.1, 00:00:20, Serial0.31

100.0.0.0/24 is subnetted, 1 subnets

O E2 100.1.1.0 [110/20] via 172.12.123.1, 00:00:20, Serial0.31

5.0.0.0/24 is subnetted, 1 subnets

O E2 5.5.5.0 [110/20] via 172.12.123.1, 00:00:20, Serial0.31

This is one of the most common errors made during route redistribution, but now you know what to look out for! In the next part of this free CCNP / BSCI tutorial, we’ll take a look at another such error.

Once you earn your CCNA certification, you’ve got quite a few exciting choices ahead of you! The majority of CCNAs go on to pursue another Cisco certification, and this is a wise decision. The more you know, the more valuable you are in today’s IT market.

A question I’m often asked by new CCNAs is “Which certification should I go after next?” Often, these new CCNAs have their eye on the Cisco Certified Security Professional (CCSP) certification. While adding a security certification to your resume is an excellent idea, I strongly recommend that new CCNAs acquire their Cisco Certified Network Professional (CCNP) certification before pursuing their security certifications. The CCNP requires you to pass three or four exams (depending on the path you choose) that will demand a further mastery of some subjects you studies to earn your CCNA as well as several important topics that you haven’t seen yet.

The CCNP builds on the foundation of networking knowledge you built when you earned your CCNA, and your CCNP study will add greatly to your skills and resume. There are some common technologies that you’ll see in many networks – BGP and route redistribution among them – that you don’t learn about in your CCNA studies. By pursuing your CCNP, you’ll also learn much more about OSPF, switching, and refine your troubleshooting skills. These are skills that will pay off in your current job as well as any future job hunting you do.

When you’re preparing for success on your CCNA or CCNP certification exams, sooner or later you’re going to want to start totally from scratch on your Cisco routers and switches. It’s easy enough to type “write erase” and “reload”, but there are a few details you have to watch if you want your home lab or rack rental devices to act as though they just came out of the box.

The first step is indeed to run the command write erase, and then reload the router. You’re going to be prompted with a question before the reload starts, though, and you have to give the right answer …. or your configuration will still be there when you reload!

First, you will be prompted to confirm the erase. Press to accept the default answer of “confirm”.

R1#write erase

Erasing the nvram filesystem will remove all configuration files! Continue? [confirm]

[OK]

Erase of nvram: complete

With the startup configuration erased, it’s time to reload the router. This is where the second prompt comes in:

R1#reload

System configuration has been modified. Save? [yes/no]: no

When a Cisco router prompts you with two answers to a question, you’ve got to type the answer in (or at least the first letter of it). Answer NO to this question and press when prompted to confirm the reload.

The router will then start the reload process. Since there is no startup configuration in NVRAM, the router will prompt you to enter setup mode. You should only answer yes if you have a lot of time on your hands, just want to see what setup mode is like, or practice CTRL-C to get out it! Otherwise, answer NO.

— System Configuration Dialog —

Would you like to enter the initial configuration dialog? [yes/no]: n

Would you like to terminate autoinstall? [yes]:y

You’ll see quite a few messages after this relating to interface states, and finally you’re back at the user exec prompt.

Router>

Now you’re working with a router that’s just like it was when it came out of the box!

For switches such as the 2950, the process is much the same, but you should delete the VLAN.DAT file before reloading the router. This file contains VLAN information and is kept in flash, so it will still be present after a reload.

switch1#write erase

Erasing the nvram filesystem will remove all files! Continue? [confirm]

[OK]

Erase of nvram: complete

switch1#delete vlan.dat

Delete filename [vlan.dat]?

Delete flash:vlan.dat? [confirm]

switch1#reload

Make sure to hit for the two questions regarding the deletion – if you answer “y” instead, the switch thinks you’re trying to erase a file named “y”!

After the reload is complete, you’ll be prompted to enter setup mode. As you did with the router, enter “N” and begin to configure the router from user exec mode. There’s nothing like working with real equipment to prepare for your CCNA and CCNP success, and there’s no better practice than configuring routers and switches from the very beginning!

In the competitive world of the internet, computer training is necessary to gain skills and knowledge in order to get the validation you need to be recognized as an expert IT professional confronting all those opportunities and career challenges that have never been greater than today.

An IT certification is a common a prerequisite to get a job or a salary increase, hence professional certifications are a necessity and not just a marketing strategy to sell determined software or useless courses. Both computer training and IT certification are the best way to demonstrate your skills and expertise in any given technical field to present to prospective employers.

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Computer training online and computer based training products also offer online support from expert instructors, which make it easier to learn without even leaving the comfort of your home. From study guides, practice exams, to audio training, video training and online training. Computer training offers different requirements and levels of learning to focus on anyone’s demands.

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More CCNA and CCNP candidates than ever before are putting together their own home practice labs. It’s more affordable than it ever has been, and I receive emails daily from new CCNAs and CCNPs who say it’s the best thing they could have done to improve their studies.

There are some commands you can configure on your lab routers that won’t necessarily be on your CCNA or CCNP exams, but they will make life a lot easier for you. Let’s take a look at just a few of these.

The command “no exec” is short, yet powerful. Occasionally you’ll have what is referred to as a “rogue EXEC” process tie up a line, and you end up having to continually clear lines, which disrupts your practice. If you have an access server, I highly recommend you configure this command on your lines, as shown here:

ACCESS_SERVER(con)#line 1 8

ACCESS_SERVER(con)#no exec

From your CCNA studies, you know that the command “no ip domain-lookup” prevents a Cisco router from sending a broadcast to find a DNS server anytime you enter something that is not an IOS command – and that includes mistyped commands, which happens to all of us sooner or later. Make sure to run that command in global configuration mode on all your practice routers.

There are two commands I like to configure on the console line on all my practice routers and switches. The first is “exec-timeout 0 0″, which prevents you from being kicked out of enable mode and back into user exec after a few minutes of inactivity. (This doesn’t sound like much, but you’ll get pretty tired of typing “enable” after a while.) The first zero refers to minutes, the second zero to seconds. Setting them both to zero disables the exec-timeout function.

The second command prevents the router from interrupting the command you’re typing with a console message. If you’ve ever been in the middle of typing a router command and suddenly you’re interrupted with a logging message, you know that can be pretty annoying. We don’t want the router to not display the message, but we do want the router to wait until we’re done entering data. The command to perform this is “logging synchronous”.

R1(config)#line console 0

R1(config-line)#exec-timeout 0 0

R1(config-line)#logging synchronous

You won’t see many of these commands on your exams, but after you configure them on your home lab devices, you’ll wonder how you did without them!

To earn your CCNP, you’ve got to pass some very rigorous Cisco exams, and you also need to know the rules regarding this important certification. In this article, I’ll answer some of the most commonly asked questions regarding the CCNP.

Q: What exams do I need to pass to get my CCNP?

A: You have two options, a three-exam path and a four-exam path. Currently, the four-exam path consists of rigorous exams on advanced routing techniques (BSCI), advanced switching (BCMSN), remote access methods (BCRAN), and advanced troubleshooting techniques (CIT). The three-exam path combines the BCMSN and BSCI exams into a single exam, the Composite exam.

Q: Do I have to take them in any order?

A: No, the order is up to the candidate. Most CCNP candidates take the BSCI exam first and the CIT exam last, but again this is up to the candidate.

Q: What else do I have to do to get the CCNP?

A: You must earn your CCNA before you can be CCNP certified (as well as passing the exams, of course).

Q: Is there a recertification requirement?

A: Cisco CCNP certifications are valid for three years. During that time, you must either pass the Composite exam, the BSCI and BCMSN exams, or pass any CCIE written exam.

Q: What if I don’t recertify within the three-year period?

A: You must then meet whatever CCNP requirements there are at that time, from the beginning. It’s easier to make sure you recertify!

Becoming CCNP certified is a great boost to your career and your confidence, and as with any Cisco certification, it’s up to you to stay current with the CCNA and CCNP requirements. Visit the Career Certification section of Cisco’s website regularly to learn about the program’s requirements and changes.

Congratulations on your decision to earn your CCNP certification! As a CCIE, I can tell you that Cisco certifications are both financially and personally rewarding.

To earn your CCNP, you first have to earn your CCNA certification. Then you’re faced with a decision – take the three-exam CCNP path, or the four-exam path? They’re both quite demanding, so let’s take a look at each path.

The four-exam CCNP path includes the Building Scalable Cisco Internetworks exam (BSCI), Building Cisco Multilayer Switched Networks exam (BCMSN), Building Cisco Remote Access Networks (BCRAN), and Cisco Internetwork Troubleshooting (CIT) exam.

The three-exam path combines the BSCI and BCMSN exams into a single exam, called the Composite exam.

I’m often asked what order I recommend taking the exams in. After earning your CCNA, I recommend you begin studying for the BSCI exam immediately. You will find the fundamentals you learned in your CCNA studies will help you a great deal with this exam. You’re going to add to your CCNA knowledgebase quite a bit when it comes to OSPF and EIGRP, as well as being introduced to BGP.

I don’t have a preference between the BCMSN and BCRAN exams, but I do recommend you take the CIT exam last. You’ll be using all the skills you learned in the first three exams to pass the CIT. It’s a very demanding exam, and it’s a little hard to troubleshoot technologies that you haven’t learned yet!

The CCNP is both financially and personally fulfilling. Once you complete your CCNA studies, take a little breather and then get started on your CCNP studies. The more you know, the more valuable you are in today’s ever-changing IT job market.

While studying to pass the BSCI exam and preparing to earn your CCNP certification, you’ll quickly notice that while OSPF and ISIS are both link-state protocols, there are a lot of differences between the two. One major difference is the way the two protocols handle hello packets.

Hello packets are imperative to keeping OSPF and ISIS adjacencies alive. Since they are both link-state protocols, neither of them will send updates at any specified time. Hello packets are the only method by which routers running OSPF and ISIS can see that a neighboring router is still available.

OSPF gives us some great options when it comes to keeping routing table size down via the use of stub and total stub areas, but to OSPF, a hello packet is a hello packet. ISIS routers are capable of sending two different types of hellos – Level 1 and Level 2.

ISIS routers are classified as Level 1 (L1), Level 2 (L2), and Level 1-2 (L1-L2). By default, Cisco routers are L1-L2 routers; this means that every ISIS-enabled interface will send out both L1 and L2 hellos.

If one of the interfaces is forming only an L1 or L2 adjacency, there’s no reason to send out hellos for the other adjacency type. For example, if R1 is forming an L1 adjacency with R2 via its ethernet0 interface, there is no reason to allow the router to transmit L2 hellos. To hardcode a router interface to send only L1 or L2 hellos, use the isis circuit-type command.

R1(config)#interface ethernet0

R1(config-if)#isis circuit-type level-1

Note: To configure this interface to send only L2 hellos, the full command is “isis circuit-type level-2-only”, not just “level-2″.

This configuration would prevent L2 hellos from being transmitted out ethernet0. While this does save router resources and prevents unnecessary bandwidth usage, there is also no way an L2 adjacency can be formed – so double-check your network topology before using this command!

One of the most common questions I get from CCNA and CCNP candidates who are setting up their own home labs is “What cables will I need?” The answer is “It depends.” As you know from your exam studies, the physical layout of your lab is what determines the cables you’ll need. Let’s take a look at the most common home lab cable types and when you will need them.

Straight-through cables have quite a few uses in a CCNA / CCNP home lab. You’ll need them to connect a switch port to an AUI port on a router (and you’ll need a transceiver for that as well). If you have an ISDN simulator, straight-through cables can be used to connect a router’s BRI port to the simulator.

Crossover cables are used to connect switches and allow them to trunk. If at all possible, get two switches in your home lab. This will allow you to gain valuable experience in manipulating root bridge election, working with STP, and creating EtherChannels.

DTE/DCE cables are used to connect two routers via their serial cables. If you are planning on using a frame relay switch in your lab, you’ll need several of these. You can also get some great practice in by directly connecting two routers and bringing the connection up (and making sure it stays up!). This is valuable practice for your CCNA exam.

Octal cables are used to connect an access server to each of the other routers and switches in your lab.

Finally, there’s that precious blue cable, the rollover cable. Rollover cables (sometimes called “rolled cables”) allow you to connect a host device directly to a router or switch’s console port. These cables have a way of disappearing around an IT shop, so make sure to take one home – and leave it there!

Whether you’re thinking of starting a career with computers and information technology, or thinking about earning a professional certification such as the CCNA or MCSE to accelerate your career, there is no better time to start than today. Silicon Valley is hiring again, and while we all can’t work for Google, IT hiring is at its highest level in years and the opportunities for driven, motivated individuals are unlimited.

I also know that for many of us, the holiday season is a good excuse to put off those studies! “I’ll study for the CCNA after Thanksgiving…” “I’ll start working on my CCNP after the New Year…” Well, guess what – the new year is here.

It’s 2006. Where is your IT career? Are you actively studying to earn a certification, or are you still thinking about it? Are you attending a school to break into the IT field, or are you still thinking about it?

Newton’s First Law Of Motion states that an object at rest tends to stay at rest, and an object at motion tends to stay in motion. This is true of careers as well, including yours. Where do you want your career to be in one year? Do you want to have earned several certifications in that time, therefore advancing your career, or do you want to be in the exact same place you are today?

The only person who can make this decision is you. And I can speak from experience that when you begin putting your career into motion – the possibilities are unlimited. But you have to get started – today!