Regular Expressions

Useful/Standard RegEx

Matches	Expression
IP Address	^\b((25[0-5]|2[0-4]\d|[01]\d\d|\d?\d)\.){3}(25[0-5]|2[0-4]\d|[01]\d\d|\d?\d)\b
Hostname (no domain)	\A(\w|-)+
Email address	\b[A-Z0-9._%+-]+@[A-Z0-9.-]+\.[A-Z]{2,4}\b

Examples

Logfile Name

\d{4}-[A-Za-z]{3}-Week\d{1}.log

Example matches...

• 2010-Feb-Week4.log
• 2009-Dec-Week2.log
• 1234-aBc-Week0.log

Between Parentheses

(?<=\[)(.*?)(?=\])

Matches everything between [ and ] , so for example...

• VMFS_SCSI_DS_01 is matched from [VMFS_SCSI_DS_01] My_VM/MyVM.vmdk

Its essentially done via three chunks of the regex...

1. (?<=\[)
   • Requires that [ immediately proceeds the match
2. (.*?)
   • Matches everything
3. (?=\])
   • Requires that [ immediately follows the match