redis_downtime.rb

redis = Redis.new(:url => 'redis://localhost:6379/1')

disconnected_at = nil

loop  do 
  begin
    
    if  disconnected_at && (size = redis.keys('testing:*').count)
      puts "reconnected_at #{Time.now}"
      puts "KeysSize: #{size}"
      break
    end
    
    redis.set("testing:#{Time.now.to_i}", 1)
    puts "#{Time.now}=>#{redis.keys('testing:*').count}" 
    
    sleep 2
  rescue Redis::CannotConnectError, Errno::EINVAL
    unless disconnected_at 
      disconnected_at = Time.now 
      puts "disconnected_at #{disconnected_at}"
    end
    retry
  end
end