1.1.b Identify Cisco Express Forwarding Concepts

Before discussing CEF one needs to be familiar with how a router actually routes a packet, these are the steps summarized: 1. Packet is received, Frame Check Sequence (FCS) is checked, if passed it moves to step 2. 2. The eth type field is is checked to indicate what the inner packet is, if 0x0800 …

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Ubuntu 17 Onenote Alternative : CherryTree

Finally, I found a suitable replacement for Onenote. Originally when searching for my replacement I immediately looked into Evernote, yet it didn't offer me anything differente compared to Onenote Online (via outlook.com). I wanted something local, with better response. Really I just needed a good way to organize my notes, I didn't need anything fancy. …

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1.1.a (iii) Excluding Specific Platforms Architecture

IOS XE does not run on every platform. Specifically it does not run on 29xx routers, low level ISRs like the 800 or 900 series. It does run on the following though: New Catalyst 9K line Converged Broadband Routers ASR line 42xx, 43xx, 44xx ISR ISRv and CSR1000v

1.1.a (ii) Impact to Troubleshooting and Performance

IOS XE also runs a separate driver instance for each blade, thus one blade driver crashing does not crash any others that use the same driver, this is because they run their own instance of the driver. Monolithic IOS runs all of the processes in one memory space, thus if the kernel crashes or has …

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1.1.a (i) Control plane and Forwarding plane

IOS-XE is able to have better logical and especially physical separation of the three planes. For example a chassis is able to have 3 blades, one dedicated to control plane, one to data plane, and one to the management plane. Granted that is a glorified example, it's possible. Since IOS XE runs a linux operating …

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1.1.a Describe basic software architecture differences between IOS and IOS XE

Cisco moving to different operating systems for their networking devices should come as no surprise. When comparing traditional or monolithic IOS to Juniper or Arista, we find IOS lacking. Specifically we find it lacking in the areas of scripting, programing, and just being able to do more. For the purpose of the CCIE, we should …

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