Cisco ASR 9000 User Manual (English)

To Next Page

To Previous Page

A-153

Cisco ASR 9000 Series Aggregation Services Router Getting Started Guide

OL-28417-02

Understanding Regular Expressions, Special

Characters, and Patterns

This appendix describes the regular expressions, special or wildcard characters, and patterns that can be

used with filters to search through command output. The filter commands are described in the Filtering

show Command Output.

Contents

• Regular Expressions, page 153

• Special Characters, page 154

• Character Pattern Ranges, page 154

• Multiple-Character Patterns, page 155

• Complex Regular Expressions Using Multipliers, page 155

• Pattern Alternation, page 156

• Anchor Characters, page 156

• Underscore Wildcard, page 156

• Parentheses Used for Pattern Recall, page 157

Regular Expressions

A regular expression is a pattern (a phrase, number, or more complex pattern).

• Regular expressions are case sensitive and allow for complex matching requirements. Simple

regular expressions include entries like Serial, misses, or 138.

• Complex regular expressions include entries like 00210... , ( is ), or [Oo]utput.

A regular expression can be a single-character pattern or multiple-character pattern. It can be a single

character that matches the same single character in the command output or multiple characters that

match the same multiple characters in the command output. The pattern in the command output is

referred to as a string.

The simplest regular expression is a single character that matches the same single character in the

command output. Letters (A to Z and a to z), digits (0 to 9), and other keyboard characters

(such as ! or ~) can be used as a single-character pattern.

Need help?

Do you have a question about the Cisco ASR 9000 and is the answer not in the manual?

Cisco ASR 9000 Specifications

General

Operating System	Cisco IOS XR
Management	CLI, SNMP, NETCONF, RESTCONF
Type	Edge Router
Interface Support	10G, 40G, 100G, 400G
Power Supply	AC and DC options available
Routing Protocol	BGP, IS-IS, OSPF, EIGRP
Storage	SSD
Operating Temperature	0 to 40°C (32 to 104°F)
Humidity	5 to 95% (noncondensing)
Redundancy	Yes (Power, Fabric, Route Processor)
MTBF	Varies by model (typically > 200, 000 hours)