re = /interface GigabitEthernet1\/(1[2-9]|[1-2][0-1]).*\n(.*\n)*.* description \*\* Unused Port \*\*.*\n(.*\n)*.* switchport access vlan 1002.*\n(.*\n)*.* switchport mode access.*\n(.*\n)*.* switchport port-security.*\n(.*\n)*.* switchport port-security mac-address sticky.*\n(.*\n)*.* shutdown.*\n(.*\n)*.* no cdp enable.*\n(.*\n)*.* spanning-tree portfast
/
str = 'interface GigabitEthernet1/12
description ** Unused Port **
switchport access vlan 1002
switchport mode access
switchport port-security
switchport port-security mac-address sticky
shutdown
no cdp enable
spanning-tree portfast
!
interface GigabitEthernet1/13
description ** Unused Port **
switchport access vlan 1002
switchport mode access
switchport port-security
switchport port-security mac-address sticky
shutdown
no cdp enable
spanning-tree portfast
!
'
subst = ''
result = str.sub(re, subst)
# Print the result of the substitution
puts result
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Ruby, please visit: http://ruby-doc.org/core-2.2.0/Regexp.html