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!