Above is a quick reminder of different Hex values, given the previous post on FHRP troubleshooting which includes the VLAN / Router Group in Hex format. Click here for my full Hex Conversion article. It will be needed for IPv6 troubleshooting! Now a quick but necessary review of IPv4 identification! It is important to be … Continue reading TSHOOT – Hex, IPv4 Addressing, DHCP, and IP NAT review and troubleshooting!
Will cover the three FHRP's for the CCNP R/S in the article, review some very basics of each protocol, and jump into commands to troubleshoot them on TSHOOT day! HSRP (Hot Standby Router Protocol) Review and Troubleshooting Review HSRP is Cisco Propriety HSRP works on both Layer 3 switches and Cisco Routers Hello 3 sec … Continue reading TSHOOT – HSRP, VRRP, and GLBP First Hop Redundancy Protocol review and troubleshooting!
Above is a visual of Private VLANs and how they can communicate with each other, however this is going to be a lot of Switch security, so lets get to it. Port Security troubleshooting Some common issues that can cause Port Security not to work: Port Security is configured but not enabled - This is … Continue reading TSHOOT – Port Security, DHCP Snooping, IP Source Guard, DAI, Protected Ports, Private VLANs, and VACL Troubleshooting!
Though router on a stick is not on current TSHOOT Topologies that I see, and will more likely be SVI's that you are troubleshooting, I wanted to add some notes on here pertaining to that subject as well for possible dated real life scenarios of dated networks. Quick review of Router on a Stick Troubleshooting … Continue reading TSHOOT – Router On A Stick, Switched Virtual Interface (SVI), Routed Ports, and Layer 3 EtherChannel troubleshooting!
Above is a simple STP topology from earlier SWITCH labbing, however this will cover all STP flavors (PVST+ / RSTP / MSTP), features that go with them, and EtherChannels. STP issues, how to identify and resolve them, and feature behaviors In relation to the TSHOOT exam, the most important thing to note is that the … Continue reading TSHOOT – Troubleshooting Spanning-Tree and Layer 2 EtherChannel issues!
The troubleshooting of Layer 2 issues seems like it may be the easiest, as the information is really taught quite thorough at the CCNA level, however there are some caveats that are potential exam landmines for TSHOOT to avoid on exam day! First I want to start with some verification commands that are critical for … Continue reading TSHOOT – Layer 2 troubleshooting of Trunks, VTP, and VLANs!
Multi-Layer Switch architecture, and how SDM can play a role in relieving the issue, and as this will only be a reference to commands to use / method of using them the following articles will need to be read or understood for the commands to make sense: Detailed review of MLS Architecture SDM templates reviewed … Continue reading TSHOOT – Troubleshooting Memory / CPU issues, and how to apply it to “follow the path” troubleshooting method!
Found this graphic of condensed definitions of error descriptions when running a command for interface gi1/1 as "show interfaces gi 1/1 counter errors" when troubleshooting a switches interface for errors. A very good full explanation of all the different output can be found at the youtube channel I stole the graphic from (shame on me) … Continue reading TSHOOT – Description of error types in “show interfaces gig 1/0/1 counters error” output!
We are almost to the Summit of the CCNP R/S and soon to be Enterprise!!! My previous TSHOOT posts to this article is unique information that you will want to know for exam day and for real life on the job purposes, otherwise going forward will be much more condensed notes that will be largely … Continue reading Almost to the Summit! TSHOOT notes will be a bit more limited, and some suggested prep materials within!
I was going to demonstrate some concepts in packet tracer to make writing out explanations a bit quicker, but I need to speed up my grind a bit here, so I'm just going to foot to the floor these next few explanation before I take a break from blogging to really put my nose to … Continue reading TSHOOT – Using CLI Tools Part 2 – Ping, Extended Ping, Traceroute, Telnet, SNMP, Netflow, EEM (Embedded Event Mgr), FTP reviewed!
I left myself with one device to assist in getting my network back up and running, and that is the Frame-Relay Switch running configuration, which I can look at the above 3 interfaces and do the "Stare and Compare" with R1 / R2 / R3 to get them reconfigured for labbing TSHOOT concepts going forward … Continue reading TSHOOT – Using CLI tools Part 1 – Network information access, Show / Logging / NTP / Debugging concepts reviewed!