I sure miss turning on my space ship / physical lab from my CCNP R/S studies 🙂 This will be a review of some fairly basic networking information that is so basic and forgettable that I should probably review it, though I am very tempted to just skip right over this portion of this weeks … Continue reading Week 3 of the Cisco DevNet Grind – Some review of well known ports, and some network info specific to DevNet usage!
To round off the Netmiko section of Python3, I'd like to show a script that will standardize the entire network here with NTP and Buffered Logging, as those two things should be absolutely configured on a network for troubleshooting purposes. The configs shown are very minimal, and definitely not best practice for production networks, which … Continue reading Python3 Network Programming – Deploying base NTP / Logging across entire network, best practices, and the raw script at the very end of the post!
If a trouble ticket pops up for these an issue with these protocols, to know if a protocols port # is not being forwarded correctly, or being blocked by an ACL somewhere, in addition to all the other misconfigurations that might go wrong. For IP SLA, perhaps someone can correct me here in the comments, … Continue reading TSHOOT – Mgmt Tools (NTP / Syslog / SNMP / IP SLA Tracking) review and troubleshooting for exam day!
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!
Config of Clock Set, NTP Server / Client, Authentication, but first Fundamentals! Without NTP not only is your network logging going to be a nightmare to match up, but various other services rely on NTP being correct, which is why my configuration of a local MLS being the Master Clock is a TERRIBLE idea! … Continue reading NTP (Network Time Protocol) – Fundamentals, Configuration, Verification, and Authentication!
As I only have two routers in my lab running IOS 15.x, and 12.x is not NTPv4 capable, I've decided to review it between just these two routers to demonstrate new features brought by 15.x code that I couldn't in my previous lab involving the whole WAN Topology. To start there are a quite a … Continue reading NTP: Demonstrated between 2 routers running IOS 15.x to demonstrate NTPv4 Authentication and other concepts! (Edited with more content 5/20/17)
I have done a "wr er" / "reload" on R1 and R5, configuring only loopbacks, and opened Fa0/1 interfaces to be Area 0 between the two. No NBMA, no oddities (hopefully), and see how it works with a lot of troubleshooting. So to begin, I'll set R1 first as the NTP master with a clock … Continue reading NTP Broadcast better demonstrated over an Ethernet segment, pretty brief and to the point to finish off the NTP section!
After quite a few days out of the study game due to illness and actually giving myself time to recover from it this time, I am back, and I am already sick of going over NTP - So this is the last but important concepts for NTP. One oddity I have noticed working with NTP … Continue reading NTP Finale – Configuring broadcast / multicast / version #, and disabling NTP all together – Time to see what breaks!
So to begin this, I apparently completely spaced writing R1 so nothing got saved, and we are back in time again: R1#sh clock *22:38:45.666 UTC Fri Mar 1 2002 R1# So I've decided to go right into Authentication first, as it's fairly straight forward with an odd behavior to note, then continue my battle with … Continue reading NTP Authentication and ACL configuration, odd behaviors explained, and issues to troubleshoot as always!
For this lab I will be using this OSPF Topology, which has the virtual-link to R4 to bring it into the entirety of the network, and to demonstrate how to configure each of these routers so they keep in sync with the entire network via NTP even if their primary time source goes down. So … Continue reading NTP – Network Time Protocol discussion, configuration, and some NTP / routing troubleshooting as usual!