Conventions used

There are a number of text conventions used throughout this book.

Code in text: Indicates code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter/X handles. Here is an example: “The following output from the PE1 router confirms that the IP addresses are applied according to the configurations on each router.”

A block of code is set as follows:

router IS-IS IGP 
interface GigabitEthernet0/0/0/3 
address-family ipv4 unicast 
metric 100

When we wish to draw your attention to a particular part of a code block, the relevant lines or items are set in bold:

interface {{ interface_name }} 
description "P(E){{ x }}_to_P(E){{ y}}" 
ipv4 address {{ xy.0.0.(x or y) }} 255.255.255.0 
no shutdown

Any command-line input or output is written as follows:

RP/0/RP0/CPU0:PE1#show isis route detail 5.5.5.5/32 
L2 5.5.5.5/32 [40/115] Label: None, medium priority 
Installed Jan 01 06:02:54.493 for 00:02:56 
via 12.0.0.2, GigabitEthernet0/0/0/2, P2, Weight: 0 
src PE5.00-00, 5.5.5.5 
RP/0/RP0/CPU0:PE1#

Bold: Indicates a new term, an important word, or words that you see onscreen. For instance, words in menus or dialog boxes appear in bold. Here is an example: “Built-in support for SR-Traffic Engineering (SR-TE), allowing operators to direct traffic through specific paths for optimized network performance.”

Tips or important notes

Appear like this.