#!/usr/bin/ruby require 'resolv' require 'optparse' require 'yaml' NAGIOS_STATUS = { :OK => 0, :WARNING => 1, :CRITICAL => 2, :UNKNOWN => -1 }; @verbose = 0; @additional_nameservers = [] def show_help(parser, code=0, io=STDOUT) program_name = File.basename($0, '.*') io.puts "Usage: #{program_name} [options] " io.puts parser.summarize exit(code) end ARGV.options do |opts| opts.on_tail("-h", "--help" , "Display this help screen") { show_help(opts) } opts.on("-v", "--verbose" , String, "Be verbose") { @verbose += 1 } opts.on("-a", "--add=HOST" , String, "Also check SOA on ") { |val| @additional_nameservers << val } opts.parse! end show_help(ARGV.options, 1, STDERR) if ARGV.length == 0 warnings = [] oks = [] dns = Resolv::DNS.new ARGV.each{ |domain| serial = [] nameservers = dns.getresources(domain, Resolv::DNS::Resource::IN::NS) nameservernames = nameservers.collect{ |ns| ns.name.to_s } nameservernames = nameservernames.concat @additional_nameservers nameservernames.each{ |nameserver| puts "Testing nameserver #{nameserver} for #{domain}" if @verbose > 0 arecords = dns.getresources(nameserver, Resolv::DNS::Resource::IN::A) warnings << "Nameserver #{nameserver} for #{domain} has #{arecords.length} A records" if arecords.length != 1 arecords.each{ |a| puts " Nameserver #{nameserver} is at #{a.address}" if @verbose > 0 resolver = Resolv::DNS.new({:nameserver => a.address.to_s}) begin soas = resolver.getresources(domain, Resolv::DNS::Resource::IN::SOA) rescue SystemCallError => e warnings << "Could not resolve #{domain} on #{nameserver}: #{e.message}" else warnings << "Nameserver #{nameserver} for #{domain} returns #{soas.length} SOAs" if soas.length != 1 soas.each{ |soa| puts " Nameserver #{nameserver} returns serial #{soa.serial} for #{domain}" if @verbose > 0 serial << soa.serial unless serial.include? soa.serial } end resolver.close } } case serial.length when 0 warnings << "Found no serials for #{domain}" when 1 oks << "#{domain} is at #{serial.first}" else warnings << "Nameservers disagree on serials for #{domain}: found #{serial.join(', ')}" if serial.length != 1 end } dns.close if warnings.length > 0 warnings.each{ |w| puts w } exit NAGIOS_STATUS[:WARNING] else oks.each{ |w| puts w } exit NAGIOS_STATUS[:OK] end