DRBD cluster facts

Some facts to help managing a DRBD cluster:

if FileTest.exists?("/proc/drbd")
  result = {}

  Thread::exclusive do
    File.readlines("/proc/drbd").each do |l|
      if l =~ /(\d+): cs:Unconfigured/
        device = $1

        result["drbdconnectionstate#{device}"] = "Unconfigured"
      elsif l =~ /(\d+): cs:(\w+) st:(\w+)\/(\w+) ld:(\w+)/
        device = $1
        connectionstate = $2
        localstate = $3
        peerstate = $4
        localdiskstate = $5

        result["drbdconnectionstate#{device}"] = connectionstate
        result["drbdlocalstate#{device}"] = localstate
        result["drbdpeerstate#{device}"] = peerstate
        result["drbdlocaldiskstate#{device}"] = localdiskstate
      elsif l =~ /(\d+): cs:(\w+) st:(\w+)\/(\w+) ds:(\w+)\/(\w+)/
        device = $1
        connectionstate = $2
        localstate = $3
        peerstate = $4
        localdiskstate = $5
        peerdiskstate = $6

        result["drbdconnectionstate#{device}"] = connectionstate
        result["drbdlocalstate#{device}"] = localstate
        result["drbdpeerstate#{device}"] = peerstate
        result["drbdlocaldiskstate#{device}"] = localdiskstate
        result["drbdpeerdiskstate#{device}"] = peerdiskstate
      end
    end
  end

  result.each { |name, fact|
    Facter.add(name) do
       setcode do
         fact
       end
    end
  }
end

It has been tested with DRBD version 0.7.24 and 8.0.4 (not sure the /proc/drbd format is the same for older versions of DRBD).

Here is a sample output from facter (indicates the state of /dev/drbd0 on the primary node while the secondary node is disconnected):

drbdconnectionstate0 => WFConnection
drbdlocaldiskstate0 => UpToDate
drbdlocalstate0 => Primary
drbdpeerdiskstate0 => Outdated
drbdpeerstate0 => Unknown