Credit: Michal Racek <michal.racek@t-systems.sk>

In Resmon 1, it was possible to add an interval parameter to an individual
check to give it a larger check interval than regular checks (cached results
would be returned in the meantime). This functionality wasn't properly carried
over into resmon 2, and this commit fixes that.

Allow setting an absent => X config param for file checks.  If set will return all the metrics the module normally would, but with their integer values set to whatever you defined for absent.  present will still = 0 and text values will be undef

Occasionally on some systems, the data returned from the shared state file is
bad/blank, despite locking. Ideally we'd find the cause of this and fix it,
but various attempts haven't identified exactly why this happens (including
running fsync after writing and before unlocking). If the data returned is
blank, we should use the latest available data rather than returning blank
data to the user/monitoring system.

This allows you to have multiple checks on the same file, but with a different
match string in order to count different types of errors.

Allow escaped commas in config parameters.  Update Core::SMART docs and stop prefixing metrics with the disk name, as Resmon already uses check_name in the final metric output.

Uses ps to count the amount of processes on a system. I've placed this
into the Linux area as I've only tested it on a Linux system (Ubuntu
11.04).

To avoid warning messages like:
"Use of uninitialized value $bits in string eq at /opt/resmon/lib/Resmon/Config.pm line 16..."
$bits variable should be checked if it is defined before comparison with empty string

Hosts allow-deny lists are the coma or blank separated lists of
a dotted decimal IPv4 addresses of the form a.b.c.d. to match incoming machine’s IP address exactly,
or an 'ipaddr/n' where ipaddr is the IP address and n is the number of one bits in the netmask.
The first to occur match gives the result, skipping other rules.
If nothing matches IP is allowed.

They are still available in the resmon1 branch if needed.

This module is meant to be generic enough that it can do any query based check against postgres. You just need to add the entry to %queries for it to be available.

The backslash at the end of the line wasn't a line continuation, and turned
the following string into a reference. Yay perl!

The generic Cpu module makes use a vmstat, and the columns used vary across
different linux installations. This improves the situation somewhat.

MemFreeBufCache == MemFree + Buffers + Cached

Add a module to report OS name/version.  Helpful for correlating events with OS changes like patching or upgrading.  Add a gitignore at the top level with resmon.conf in it.  This will prevent the loss of a live conf file during a git clean.

The filter patterns for identifying local port/remote port and so on are taken
directly from the resmon 1 module. They look like they could use some
improvement to prevent some misdetection, but if the resmon 1 module worked
for your purposes, the resmon 2 module should also.

If a client connection dies (connection reset by peer) then previously the web
server would just exit. This shouldn't happen.