@Abraham-Oz,
Make sure that you download the official exam blueprint from Cisco for ENCOR and ENARSI. This will list definitively what topics are covered on the exam for you.
The ROUTE, SWITCH and T-SHOOT are helpful in the fact that majority of the material is covered in there for both of the ENCOR and ENARSI. There are objective domains, at least one, that are not covered in that material. I can think of the virtualization
and automation
domains. Mastery of course is the ultimate goal. In preparation for the ENCOR exam specifically this is where Anthony's approach can help you scope more appropriately.
As far as recommendations of the OSG for ENCOR and ENARSI. They are written for a particular audience, which is the person who is ultimately seeking the CCIE in Enterprise Infrastructure. This means the topics though covered on ENCOR exam, they are covered at a very detailed level that does over prepare you for the exam. This is fine but it's not scoped for the person looking to sit the exam within a relatively short time...it is scoped for preparing you for the CCIE exam. This makes sense in the fact that ENCOR is the equivalent of the "CCIE Written" exam now. I recommend that you use these particular guides to help you on difficult topics you need more guidance.
Cordially,
Ronnie Wong
Edutainer Manager, ITProTV
*if the post above has answered the question, please mark as solved.
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