Going back to this above visualization of 2-way Redistribution which is a perfect case use for a Route-Map to perform "Route Tagging" for routes being Redistributed, which assigns tag # values to Routes as they Redistribute and can filter (drop) routes that contain a certain tag value to ensure routes are not re-learned into their … Continue reading TSHOOT – Redistribution Part 4 – Route-Map review, and COMPLETE review of Redistribution issues and Troubleshooting – Must know info for exam day!
Route-Maps are used for multiple different purposes as shown in the example above, this specific Route-Map itself would never exist in a real world scenario, because the sequences demonstrate several different use cases for Route-Maps in the sequences. Review of sequences from the Route-Map posted above A few concepts of Route-Maps is that the "permit" … Continue reading TSHOOT – Route-Maps, Policy Based Routing (PBR), and Local Policy Routing review and troubleshooting!
I will be using this Topology not as an OSPF course, but to perform Policy Based Routing (PBR) to influence how traffic travels from R5 to destination network 18.104.22.168, but first we need to review the basics of PBR: PBR effects packets on the Ingress interface it is configured on, not traffic generated by the … Continue reading Policy Based Routing / Local Policy Routing, and Route-Map configuration and explanation, review for exam day!
So as can be seen we have no NBMA in this topology, only Serial Links and an Ethernet segment, which almost makes feel naked without a Frame-Switch in there somewhere. So to begin, my last post included on the tail end a "sh ip bgp" to demonstrate something with a bunch of loopbacks being advertied … Continue reading BGP – The Multi-Exit Discriminator (MED) / Metric explained, configured, and we see some old friends ACL’s and Route-Maps to help accomplish the goal!
Not /fin with this Topology of course, after this lab of fine tuning some sub-optimal routing I am taking copies of all "sh run" to be able to spin this lab up again if it ever gets the "wr er", however it will be /fin for review and onto the subject of VPN's. So, Part … Continue reading Part 6: Troubleshooting of sub-optimal routing via route-maps / redist/ policy routing, and an old friend OSPF distance comes to save the day! (GREAT review!)
I took a quick moment to post before this, advising not to study or lab tired, cause as can be seen towards the end of my Part 4 of this lab I am just tired and swinging at air. Anyway, we now have R1 and R3 both acting as ASBR's, with R1 doing 2-way route-tagged … Continue reading Part 5: Turning “IP Routing” on for Layer 3 SW1, Policy / Local Policy Routing, found sub-optimal routing due to AD! (Will be 6th lab to troubleshoot)
(Added interface #'s to the Topology as we increase working with both IP's and interfaces) I wanted to touch this quick before moving on to policy routing, whether Distribute-Lists can block certain networks from a Summary Route, or if it's possibly at all. So I'll run through it quick here to move on: Distribute-List … Continue reading Part 4: The right ACL for the right job (Distribute-List vs Route-Map), Configuring 3-way Route Redistribution with a lot of failures but final success!!!
(The title may be misleading as ACL's will only be used for Distribute-List configuration) As seen above I have though out how to keep all the route tagging that will need to occur straight in my mind, so the route tags for EIGRP will be their AS #'s, and OSPF / RIP will be using … Continue reading Part 3: DEEP Dive into Redistribution with Route-Map tagging, and Distribute-Lists illustrated for clarity!
As previously mentioned I believe, this will be a multi-part lab in which I will configure "Multi-Point" 2-way Redistribution / Policy-Routing / Distribute-Lists / Route-Maps / and troubleshooting all along the way. Here are a few things I know I want to achieve over the several parts of this lab: Authentication deep dive for … Continue reading Part 1: Setting up the new, bigger, and better lab to configure everything we’ve learned up to this point!
Still working with the same Topology seen above, I want to round off the Policy Routing videos to see if I can bring that into some scenario or freestyle lab, and see how crazy one can get with Policy Routing. The first thing to note that I have amazingly not known at all until this … Continue reading The extended traceroute command, and Local Policy Routing Configuration!
As seen in the previous look at policy routing using a standard ACL, it led to sub-optimal routing due to only routing on the source, and not both source and destination addresses - for this we will use an Extended ACL to correct. So I took the old commands off, nothing fancy: R1(config)#no access-list 5 … Continue reading Using Extended ACL’s for Policy Routing to overcome sub-optimal routing
Boy do I feel stupid. After spending hours of scratching my head at why this is not working yet, as OSPF seems to be gettings tags but RIP is not, that is when I really put my work under a microscope and found that I was applying OSPF2RIP in OSPF router config and the other … Continue reading Part 3: Finally got Route-Maps for Redistribution working correctly, important notes within on how!
So to begin this, right off the bat I am having trouble seeing some routes on R1 from R4, as I just did a "wr er" and reloaded / reconfigured it to be directly connected. However, on R4, things couldn't possible be going better, I created lo5 and lo15 to simulate those networks from the … Continue reading Part 2: A struggle getting RIP on R1 to get any Redistributed OSPF, may need router reconfigs
Above is a "Single-Point 2-way Redistribution" in our network, which is honestly not going to (probably ever) present a loop from sharing or "leaking"routes back into their own domains, however route-tagging usefulness goes beyond just Redistribution as we will see it I assume in the next topic up PBR (Policy Based Routing / Policy Routing) … Continue reading Part 1: Route-Map tagging for 2-way Redistribution, a prevention mechanism for routing loops!
So where Part 1 of this lab left off, we learned that without that "catch all" clause at the end permitting traffic, then it is dropped like an ACL would. Going through the 2-way Redistribution video, I also learned that sequence #'s do also work exactly like ACL's, so you will want to plan your … Continue reading Part 2: Understanding Route-Map Sequence significance, Clauses, and lots of details to finish this Route-Map lab!