###############################################################################
# crinv (Create Inventory Report) v0.9 (10-Jan-2010)
# Copyright (c) 2009-2010 Tassos (http://ccie-in-3-months.blogspot.com/)
#
# crinv is a perl script that processes a text file with a list of devices (routers & switches),
# then it gets info from them by using the SNMP Entity-MIB,
# and finally it creates a csv file with parts info per device in a kind of hierarchical format.
#
# Format of devices' file
# -----------------------
#  - The general format of each line is "device|community"
#  - Only device is required, community is optional
#  - All white spaces are removed before processing each line
#  - Lines starting with # are comments and will be ignored
#  - Lines starting with | are ignored
#  - The | character must be used on each line for seperation between device and community
#  - Devices without a community use the default/cli community
#  - Lines without a | character are considered to be devices and use the default/cli community
#
# Output csv filename is created automatically after removing any extension from the 
# devices input filename and adding .csv to it
#
# In order to make the output kind of hierarchical, you have to change the following two parameters:
# 
# my $left_space = " ";  # This can be any character(s) you want to use to produce the left indent effect
#                        # spaces are prefered since tab characters do not show up in Excel
# my $display_level = 1; # This must be 1 for hierarchical output
#
# Examples:
# ---------
#  - crinv -d devices.txt -c SNMP-COMM
#      Process all devices from devices.txt and use SNMP-COMM as a community name for devices
#      that don't have one
#  - crinv -d devices.txt
#      Process all devices from devices.txt and use the default community name for devices
#      that don't have one
#
# The following information can be included in the generated csv file:
#
# entPhysicalDescr : A textual description of physical entity
# entPhysicalName : The textual name of the physical entity
# entPhysicalHardwareRev : The vendor-specific hardware revision string for the physical entity
# entPhysicalFirmwareRev : The vendor-specific firmware revision string for the physical entity
# entPhysicalSoftwareRev : The vendor-specific software revision string for the physical entity
# entPhysicalSerialNum : The vendor-specific serial number string for the physical entity
# entPhysicalModelName : The vendor-specific model name identifier string associated with this physical component
#
# Check Entity MIB (ftp://ftp.cisco.com/pub/mibs/v2/ENTITY-MIB.my) for more details.
#
# Please note that not all Cisco devices support the Entity MIB and those that support it, do not
# always display the correct information.
#
# The following modular devices have been tested (with latest IOS) and seem to return correct values:
# 6500, 7600, 10000, ASR1000, 12000.
#
# The following smaller devices have been tested (with latest IOS) and seem to return correct values:
# 2950, 2960, ME3400, 3750, 3845, 7200/G1, 7200/G2. 7200s may show a different S/N than the actual one.
#
# Required Perl modules:
# ----------------------
#  - Net::SNMP
#
################################################################################
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License as published by
#    the Free Software Foundation, either version 3 of the License, or
#    (at your option) any later version.
#
#    This program is distributed in the hope that it will be useful,
#    but WITHOUT ANY WARRANTY; without even the implied warranty of
#    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#    GNU General Public License for more details.
#
#    You should have received a copy of the GNU General Public License
#    along with this program.  If not, see <http://www.gnu.org/licenses/>.
################################################################################
#
# History
#--------
# v0.1 30/10/2009 initial version
# v0.2 04/11/2009 multiple devices supported
#                 device name added to output
#                 filtering added to model name
#                 minor improvements
# v0.9 10/01/2010 major rewrite
#                 external snmp script deprecated
#                 Net::SNMP integration
#                 uploaded to code.google.com
#
###############################################################################

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