About Cisco IOS Software Documentation
Document Conventions
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Cisco IOS IP Configuration Guide
Command syntax descriptions use the following conventions:
Nested sets of square brackets or braces indicate optional or required choices within optional or
required elements. For example:
Examples use the following conventions:
The following conventions are used to attract the attention of the reader:
Caution Means reader be careful. In this situation, you might do something that could result in
equipment damage or loss of data.
Note Means reader take note. Notes contain helpful suggestions or references to materials not
contained in this manual.
Timesaver Means the described action saves time. You can save time by performing the action
described in the paragraph.
Convention Description
boldface Boldface text indicates commands and keywords that you enter literally as shown.
italics Italic text indicates arguments for which you supply values.
[x] Square brackets enclose an optional element (keyword or argument).
| A vertical line indicates a choice within an optional or required set of keywords or arguments.
[x | y] Square brackets enclosing keywords or arguments separated by a vertical line indicate an optional
choice.
{x | y} Braces enclosing keywords or arguments separated by a vertical line indicate a required choice.
Convention Description
[x {y | z}] Braces and a vertical line within square brackets indicate a required choice within an optional element.
Convention Description
screen Examples of information displayed on the screen are set in Courier font.
boldface screen Examples of text that you must enter are set in Courier bold font.
< > Angle brackets enclose text that is not printed to the screen, such as passwords.
! An exclamation point at the beginning of a line indicates a comment line. (Exclamation points are also
displayed by the Cisco IOS software for certain processes.)
[ ] Square brackets enclose default responses to system prompts.