Exam Profile: CCNA Data Center DCICN 640-911
Date: Aug 22, 2014
The DCICN 640-911 exam serves as the very first exam in a journey toward any Cisco Data Center certification. To put CCNA Data Center in context, this article reviews the history of the Cisco Data Center certifications. It then discusses one of the biggest differences between the Cisco Data Center certs and other tracks: The fact that the CCNA Data Center certification includes both networking and computing content. The rest of the article then focuses on the CCNA Data Center certification, the DCICN exam in particular, and how to prepare for that exam.
History of Cisco Data Center Certifications
Networking has been an important part of Data Centers for almost the entire history of Information Technology (IT). The earliest computer networks connected user terminals and printers to the applications running in the Data Center. Over time, the details of what makes up a Data Center have progressed tremendously, and networking's role has progressed as well—in both importance and complexity.
Data Centers have been transformed by virtualization and cloud computing. Today's virtualized Data Centers allow great flexibility, for example: applications to move between server OS instances; server instances (virtual machines) to move to new server hardware; and server resources (CPUs, RAM, etc.) to be reallocated to the needs of the VMs. Storage, formerly sitting on a disk drive inside a physical server, sits on a storage area network (SAN), also allowing great flexibility. To make all these Data Center features work, network technology has progressed by adding networking features unique to the needs of Data Centers.
Cisco has long been the leading company in traditional networking, but it has established a leadership position in storage networking and a highly competitive position in server computing technologies. Cisco began offering SAN products in the early 2000s, helping lead the transition from separate SANs to converged products that support both storage and more traditional networking with Ethernet LANs.
Cisco also launched its Unified Computing System (UCS) family of products in 2009: server hardware built with virtualization in mind, with an eye toward easier integration with the storage and networking features required in every Data Center. (And in June 2014, the Cisco UCS achieved the #1 market position in the x86 Blade server market.)
The tremendous growth in Data Center technology over the previous decade has led to a much greater need for skilled engineers with a skillset geared towards Data Centers. Cisco actually had a CCIE Storage certification for those early years of Cisco's SAN products. Then, in 2012, Cisco morphed CCIE SAN into CCIE Data Center. That same year, Cisco added the CCNA Data Center and CCNP Data Center certifications as well. The result: a traditional complete CCNA/CCNP/CCIE certification track for Cisco Data Center technology.
Cisco Data Center Certifications: Networking and Computing
The Cisco Data Center certification track as a whole, from CCNA through CCIE, requires about as much attention to the compute features in Cisco UCS as it does for networking features. As evidence for this relative equality between coverage of networking vs. computing:
- The CCNP Data Center certification requires that you pass four exams: you must choose two exams that happen to focus on networking and two that happen to focus on computing.
- Cisco lists a percentage weight for each major section of the exam (per the list of exam topics). If you look at the CCNP Data Center and CCIE Data Center exam topics in particular, those weightings work out to roughly the same for networking topics and computing topics.
Note that this comparison puts both storage networking and traditional networking together.
However, the CCNA Data Center certification focuses much more on networking than on computing. In fact, the DCICN exam has no real coverage of compute or storage; the DCICT 640-916 exam (typically the second of the two CCNA Data Center exams that you would take) introduces compute and storage while still covering more networking (at least per the weighting information in Cisco's exam topics.)
CCNA Data Center and the DCICN 640-911 Exam
The CCNA Data Center certification requires that you pass two exams with no other prerequisites. Although you can pass the exams in either order, most people start with the DCICN 640-911 exam because DCICT relies on knowledge obtained in DCICN.
DCICN focuses on networking—no storage networking and no compute—as implemented on Cisco's Nexus family of Data Center switches. The major topics include these:
- Layer 2 Ethernet switching
- Layer 3 IPv4 routing
- General networking concepts
- Spanning Tree Protocol
- Virtual LANs and VLAN Trunking
- IP Routing Protocols and OSPF
- IP Access Control Lists
- Implementing and verifying these features on Nexus switches
Note that the end of this post lists the now-current DCICN 640-911 exam topics as of the time this article was posted. However, you should always check www.cisco.com/go/ccna and navigate to the correct exam to check the latest exam topics.
One big difference between the Cisco Data Center certifications, including the DCICN exam, is the focus on the Nexus switch product line and its operating system, NX-OS. The Cisco Nexus product line supports layer 2 Ethernet switching, layer 3 switching (IP routing), storage networking, various advanced protocols to support Data Center functions, and with virtual switch options to help create virtualized Data Centers. The DCICN exam includes details of NX-OS support of layer 2 Ethernet switching and layer 3 IP routing, plus related protocols.
Unlike many of Cisco's other CCNA certifications, the CCNA DC certification does not require the CCENT or CCNA Routing and Switching certification as a prerequisite. One reason Cisco does not require any prerequisite is that the DCICN exam topics have a large amount of overlap with the CCNA R/S exams. In fact, the ICND1 100-101 exam (which earns you the CCENT certification) sets the foundational skills for a career in networking using Cisco routers and Cisco Catalyst switches, whereas the DCICN 640-911 does the same, for many of the same concepts, but with the implementation on Nexus switches.
The following figure shows the current CCNA certifications with the minimum prerequisites. Note that CCNA Data Center, CCNA Video, and CCNA Service Provider are currently the only ones that do not require at least a CCENT certification as a prerequisite.
Exam Details
- Exam Number: 640-911
- 65-75 Questions
- Question types: Multiple choice (single and multiple answer), drag-and-drop, Sim, Simlet, and Testlet (see an exam tutorial here)
- Passing score varies, but it is around 800-850 out of 1000
- 90 minutes
- Multiple languages
- Register at vue.com
Preparation Hints and Trouble Spots
DCICN may well be your first Cisco certification exam. Beyond learning the technology for the exam, you need to learn about the Cisco testing environment and the types of questions. Cisco provides an exam tutorial that reviews those question types—just go to www.cisco.com/go/ccna, navigate to the DCICN exam (or any other exam for that matter), and find the link for the exam tutorial.
Those who have already gotten their CCENT or CCNA Routing and Switching certification have a much smaller effort to pass the DCICN exam. Almost all the conceptual topics in DCICN overlap with CCNA R&S, and many of the NX-OS commands mirror the router IOS and Catalyst IOS commands you learned for CCNA R&S.
IPv4 subnetting has long been a feared and important topic for the CCENT and CCNA Routing and Switching exams. The DCICN exam covers those same topics, so you need to work hard and master IP addressing math. Knowing IPv4 addressing math well may be a little less vital in the Data Center certification track, but it is still important, and Cisco wants you to build a good foundation here in this first exam.
DCICN moves into details of Ethernet layer 2: Ethernet basics, VLANs, and STP. Interestingly, these topics include most of the LAN-specific topics in both the exams (ICND1 and ICND2) in the CCNA R&S track. Ethernet topics play an important role in all the exams in the Data Center track, through CCIE, so learn these topics well.
By percentage, the topics related to implementing IP routing on Nexus hardware take up 52% of the focus of the test. The topics include all the IP routing theory that overlaps with CCENT: IPv4 addressing, encapsulation, matching routes, and routing protocols. It includes Nexus specifics: how to boot a Nexus switch, how to configure IP routing, what the IP routing table looks like, and how routing (also called layer 3 switching because the device is both a switch and a router) works inside a Nexus switch. DCICN is both a switching and a routing exam, and by percentage in the exam topics list, may well be more of a routing exam than a switching exam.
Getting hands-on experience is a challenge with the Data Center track. Even used Nexus switches are more expensive than most self-study candidates choose to afford. However, some options exist. A Cisco offering, Cisco CloudLab, gives free access to some hosted Nexus labs in which you can get some experience. Look at the CCNA Data Center community at the Cisco Learning Network for more information.
The Cisco Nexus 1000v software switch can be installed on your own server and used for testing some functions, and for learning the NX-OS user interface. Plus, Cisco has begun to roll out virtual lab products during 2014, with names that include the phrase "VIRL" and "CML", which include NX-OS support on the roadmap. Watch for those product announcements because they may provide the best long-term solution for lab preparation for the Data Center track.
Finally, connect with the best Cisco exam preparation community: The Cisco Learning Network (CLN) http://learningnetwork.cisco.com. The Cisco Learning Network provides forums for each certification, allowing good discussions and answers to your questions.
Recommended Study Resources
At the time this exam profile was posted, Cisco Press was rolling out a Certification Guide (book) and a Live Lesson (video) product for the DCICN exam, to be followed later by a book and video products for the DCICT 640-916 exam.
The printed DCICN 640-911 Official Cert Guide focuses on the technology included in the DCICN exam, while providing a variety of exam preparation tools. Each chapter and major part of the book ends with review activities. The book notes the most important topics to study for the exam (key topics). It also includes a DVD question bank with exam software.
You may also want to use the Premium edition of the book, either in addition to the print book or instead of the print book. CCNA Data Center DCICN 640-911 Official Cert Guide Premium Edition eBook and Practice Test is the typical Cisco Press Premium eBook product. With this product, you get the book in many eBook formats, appropriate for Amazon Kindle, Barnes and Noble Nook, PDF, and other formats. Additionally, the premium edition comes with all the DVD content that comes with the printed book, but in downloadable format.
Finally, the premium edition comes with additional practice questions not found with the print book. With the substantial discount offered in the back of the print book, many people use this product in addition to the printed book, to get access to the extra questions, and for the convenience of the eBooks.
Cisco CCNA Data Center DCICN 640-911 LiveLessons is a unique video product that provides a solid understanding of the key areas of knowledge required to pass the 640-911 DCICN exam. The 5+ hours of video instruction presented in this product walk through each topic of the exam blueprint so you can gain knowledge of networking concepts for the Data Center environment based on Nexus-OS. These videos will also provide fundamental information on understanding how a Data Center network works. The course will also detail virtualization configuration in the network, addressing schemes; configuration skills, and troubleshooting methods. The videos consist of live video training, video screencasts, and demos. Video instruction throughout offers detailed explanations, tips, and design recommendations.
Major topics include these:
- Basic Networking Concepts
- Layer 2 Switching Using Nexus
- IP Addressing
- Layer 3 Routing Using Nexus
- Security
Exam Objectives
1.0 Describe How a Network Works
- 1.1 Describe the purpose and functions of various network devices
- 1.1.a Interpret a network diagram
- 1.1.b Define physical network topologies
- 1.2 Select the components required to meet a network specification
- 1.2.a Switches
- 1.3 Use the OSI and TCP/IP models and their associated protocols to explain how data flows in a network
- 1.3.a IP
- 1.3.b TCP
- 1.3.c UDP
- 1.4 Describe the purpose and basic operation of the protocols in the OSI and TCP models
- 1.4.a TCP/IP
- 1.4.b OSI Layers
2.0 Configure, Verify and Troubleshoot a Switch with VLANs and Interswitch Communications Using Nexus
- 2.1 Explain the technology and media access control method for Ethernet networks
- 2.1.a IEEE 802 protocols
- 2.1.b CSMA/CD
- 2.2 Explain basic switching concepts and the operation of Cisco switches
- 2.2.a Layer 2 addressing
- 2.2.b MAC table
- 2.2.c Flooding
- 2.3 Describe and Configure enhanced switching technologies
- 2.3.a VTP
- 2.3.b VLAN
- 2.3.c 802.1q
- 2.3.d STP
3.0 Implement an IP Addressing Scheme and IP Services to Meet Network Requirements in a Medium-Size Enterprise Branch Office Network Using Nexus
- 3.1 Describe the operation and benefits of using private and public IP addressing
- 3.1.a Classfull IP addressing
- 3.1.b RFC 1918
- 3.1.c RFC 4193
- 3.2 Describe the difference between IPv4 and IPv6 addressing scheme
- 3.2.a Comparative address space
- 3.2.b Host addressing
4.0 Configure, Verify, and Troubleshoot Basic Router Operation and Routing on Cisco Devices Using Nexus
- 4.1 Describe and Configure basic routing concepts
- 4.1.a Packet forwarding
- 4.1.b Router lookup process (exec mode, exec commands, configuration mode)
- 4.2 Describe the operation of Cisco routers
- 4.2.a Router bootup process
- 4.2.b POST
- 4.2.c Router components
Where to Go from Here
Passing the DCICN 640-911 exam moves you one step closer to a CCNA Data Center certification, but it does not complete the task. Your next step after DCICN is simple: study for and pass the DCICT 640-916 exam. Then consider when to tackle the next big hurdle: CCNP Data Center.