1 Second Default VRRP hello timer Default Group Specific Query interval (Maximum Response Time of 10) for IGMPv2 2 Seconds Default IEEE 802.1D STP hello timer Default IGMPv2 Last Member Query Count x 2 3 Seconds Default GLBP hello timer (Cisco IOS) Default HSRP hello timer (Cisco IOS) 5 Seconds Default EIGRP hello timer on …
Category Archive: Tips and Tricks
May 22
TCL Script: Ping
Difficulty Rating: Practical use case: To see what has connectivity in the network Scenario: IGP and EGP routing protocols have converged and are stable. You now want to perform end-to-end connectivity testing to check for faults using ping (or traceroute) Instructions: On each device run the command #show ip alias. This will …
TCL Scripts
For those that don’t know, TCL (pronounced Tickle) is a method of creating and running scripts on Cisco devices, mainly routers and switches. These can range to do anything from configuring device components to pinging remote addresses. To write a script you need to go into the TCL Shell on a device, accessed from Priv EXEC …
IP Protocol Numbers
The below table lists common IP protocols and their well-known numbers. The authoritave list can be found on the IANA website here Protocol Number Protocol 1 ICMP 2 IGMP 6 TCP 17 UDP 41 IPv6 in IP Tunnel 47 GRE 50 ESP 51 AH 88 EIGRP 89 OSPF 103 PIM 112 VRRP 115 L2TP
Cisco Document Locations
Below is a list of all the locations for documents of topics covered in the CCIE Lab Exam. Click the Section of the document to link straight to it. Section Topic Location Link Section Heading Library Document Section Infrastructure Security Control Plane Policing Products IOS and NX-OS Software IOS IOS Software Release 15M&T …
Router Password Reset
The Problem: We’ve all been there – a ticket comes your way where someone asks you to change a config of a device router that no one has touched for ages. You ask around the NOC for the password and you’re met with a variety responses like: “Its not documented in the password sheet” …
IOS Break Sequence
The Problem: There are 2 parts to this problem really: 1. You know how sometimes you want to just stop the router from doing its current task in the console, probably because you made a mistake or fat fingered the keyboard? Normally this includes things like ping, trace route or the dreaded DNS lookup (that …
Router Menus
Recently I have been doing quite a bit of labbing and one thing I have noticed is that there always seems to be repeatable elements such as the IP addressing, interface assignments. or if doing a BGP lab then the IGP configuration. I find that doing this isn’t really adding any value to the lab …