Now I've spent hours and hours trying to figure GRE out, this was not included in my CCNP ROUTE material except for some DMVPN using mGRE, however I did want to know for practical purposes how to encapsulate broadcast / multicast traffic over an IPSec tunnel which in turn needs a GRE tunnel as there … Continue reading VPN: DEEP Dive into GRE Tunnel configuration over OSPF, explanation of behaviors and how to overcome them!
This first image is a break down of the different types of VPN Packet Type by the headers / trailers (or lack thereof), and the following of your typical IPSec VPN Packet Type: The VPN generic representation of the IPSec VPN Packet above works for a general review, but there are details in the headers … Continue reading VPN: DEEP Dive into different VPN Packet Types, Packet Headers, and the differences between VPN Packets and their Modes!
One thing that was lacking from Chris Bryants training that I found in the INE series is explanations between when to use OSPF Filter-list vs a Distribute-list. I have modified the network as reflected in the Topology so Area 34 will no longer be a stub, and Area 15 will only be an NSSA Area. … Continue reading OSPF: DEEP Dive – Distribute-List vs Filter-List, and reviewing Prefix-Lists as Filter-Lists use Prefixes to filter!
Since I already have the lab configured with different OSPF Area's, and we had a riveting exploration into the world of LSA's and the LS DB of each router, I wanted to hit some other topics again thoroughly before I switch up protocols for more DEEP Dives into all things CCNP ROUTE related! Without further … Continue reading OSPF: DEEP Dives into Summarization methods, Authentication, Default-Information Originate (Always)!
To lead off where we left, we made Area 15 an NSSA Area which stopped the Type 4 and 5 LSA's from entering the Area, now we are going to do some Redistribution the other way and turn R5 in the NSSA Area into an ASBR. I've created networks (loopbacks) 18.104.22.168 /32 and 22.214.171.124 /24, … Continue reading Part 3: OSPF LSA DEEP Dive LSA Type 7, DEEP Dive into OSPF Stub and NSSA Areas, and how they impacts LSA traffic!
I will start this off by stating that we will start redistribution on the ASBR specified R2 to examine LSA types 4 and 5 (and where we can spot them), and R1 will eventually also be turned into an ASBR when we redistribute some loopback routes into the NSSA Area so we can review type … Continue reading Part 2: OSPF LSA DEEP Dive, LSA Types 4 / 5, and turn Area 15 to an NSSA to see what happens with the LS Database!
So we are back to OSPF, as I never really went into a deep dive with LSA types, or the LSA DataBase from different routers to show their perspective of the OSPF network caused by these Link State Advertisements. I've only configured base OSPF and RIP configurations in this lab so far, the above Topology … Continue reading Part 1: OSPF LSA DEEP dive, starting with LSA Types 1 / 2 / 3, and an Intro to all LSA Types and OSPF Routers types!
So I got a spanking big time from the INE ROUTE practice exam, which follows with video answers of both why the answer were either right or wrong, as well as highlighting where to look on the Topology to meet the criteria of the objective. One thing that I picked up was a subnetting trick … Continue reading Got my butt KICKED on INE practice ROUTE exam, but got a really helpful tips that I will continue to update on this post!
This topology has served me well so far through NAT / PAT so I will stick with it! Now PAT also known as Port Address Overload allows private IP addresses of inside hosts on your network to be translated to a single routable address with a random port number, so that a single address can … Continue reading Port Address Translation (PAT) explained, easy configuration, brief NVI0 mention, and thats it for the video series!
Once again I will be using R2 as our Dynamic NAT router for the Ethernet network, and the fundamentals of it are really just that it operates exactly like Static NAT, except we configure a pool of outside or "global" addresses that the inside "local" addresses can dynamically get used as needed. Now for the … Continue reading Dynamic NAT (DNAT) configuration, explanations along the way, verification commands, and important info for exam day!
I will use the IP SLA Track lab Topology to use SW1 as a host to perform the NAT on R2, however I have given the Ethernet segment a sub-network makeover! So to preface this I thought it was a good idea just to throw up the RFC 1918 IP address ranges, as they are … Continue reading RFC 1918 Range refresher, NAT Terminology, Static NAT fundamentals, configuration, and demo of SNAT in use!
You heard it, after this quick lab, got NAT and PAT to go over and the next week or so will be reading and labbing my butt off until exam day on 4/28. With that being said, this lab will piggy back on what we've learned, only this is a more practical real-world scenario that … Continue reading Tracking SLA for failover of static routes, explanation, and configuration – Almost to the end of ROUTE video series!!
To begin, I'd like to start with a stark contrast between Frame-Relay CIR (Committed Information Rate) provided by the FR provider, and IP SLA. As the FR Provider guarantees at least a certain up-time and bandwidth availability, that makes no claims for over-utilization or perfect uptime, and this helps to have those minimums in place … Continue reading IP SLA fundamentals, deep dive into explanation of operation, configuration, and verification commands / behaviors!
Once again, this is a no non-sense post, with no Topology associated to it (though there will be some router output to demonstrate things). I'll do this one bullet point style, think it makes the points jump out a bit more: CEF is described as Layer 3 Switching, but this means packet switching, not frame … Continue reading CEF (Cisco Express Forwarding), L3 “Switching”, RIB / FIB explained, and a ton of good info important for exam day!
Private AS Numbers: When you look at router bgp ? you see (1-65535), which the range of 64496-65535 are actually reserved or Private AS's, which should not be advertised Externally as Private IP's on your LAN should not be advertised to External networks. Also to note, you cannot use AS 0, and will get an … Continue reading BGP Private AS’s, RID, Redistribution, and some other quick but important information for success on exam day!