This is a very quick post to provide some documents to read and study if you are interested in learning DMVPN technology. I added a very short comment for each suggested link/study resource.
- Quick Guide + link for workbook:
https://learningnetwork.cisco.com/docs/DOC-24227
I’ve found that this link i a very good point where to start. It is not exaplaining in too much details the technology but gives good examples and a very good workbook to practice a bit.
- DMVPN fundamentals in phase 1, 2 and 3:
http://blog.ipspace.net/2011/01/dmvpn-phase-1-fundamentals.html
http://blog.ipspace.net/2011/01/dmvpn-phase-2-fundamentals.html
http://blog.ipspace.net/2014/03/the-fundamental-difference-between.html
Above links are another good overview about DMPVN with dedicated explanations of the three phases.
- Another quick overview with examples:
http://packetlife.net/blog/2008/jul/23/dynamic-multipoint-vpn-dmvpn/
- Main Document from Cisco.com:
http://www.cisco.com/c/en/us/products/collateral/security/dynamic-multipoint-vpn-dmvpn/data_sheet_c78-468520.html
This link is coming directly from Cisco.com and as you can imagine you can consider it as a reference. Definitely to add to your bookmarks!
- Configuration Guide from Cisco.com for IOS 15.X:
http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/sec_conn_dmvpn/configuration/15-mt/sec-conn-dmvpn-15-mt-book.html
http://www.cisco.com/c/en/us/support/docs/security-vpn/ipsec-negotiation-ike-protocols/29240-dcmvpn.html
I don’t need too many words to describe what these links are for. Definitely a great resource especially for configuring services and labs from scratch. The second one has also some specific details about the configuration of the encryption that is very often seen in production.
- From INE Blog:
-Part 1 about DMVPN Phase 1 and 2
http://blog.ine.com/2008/08/02/dmvpn-explained/
-Part 2 about DMVPN Phase 3
http://blog.ine.com/2008/12/23/dmvpn-phase-3/
I expect that you all know INE. When you want to go deeper in Networking you have to read their articles and watch their videos. Definitely the best resource on the web!
- About the Design:
Of course you can be interested also in design of DMVPN and this is a good point to start.
- Free INE videos:
- Introduction to DMVPN :: Part 1
https://www.youtube.com/watch?v=CIWcYSClbio
- Introduction to DMVPN :: Part 2
https://www.youtube.com/watch?v=DA9K0eGG17E
Great resource from INE and for free!!
The above are some of the resources I found interesting to read to have a little bit of familiarity with DMVPN subject. If you want to read more and you have the opportunity, I suggest to also have a look at the Chapter 10 of the book CCIE Routing&Switching v 5.0 Official Certification Guide, volume II, where you can find a very good explanation of the theory and the configuration. Moreover, once you will be more familiar with DMVPN technologies I suggest to watch dedicated video streams from Ciscolive365.com website. I am talking in particular about the videos with reference BRKSEC-3052.
Anyway I will soon publish a GNS3/IOU file with a topology to play with DMVPN 
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