# File lib/specinfra/command/linux/base/interface.rb, line 26
    def check_has_ipv6_address(interface, ip_address)
      ip_address = ip_address.dup
      if ip_address =~ /\/\d+$/
        ip_address << " "
      else
        ip_address << "/"
      end
      ip_address.downcase!
      "ip -6 addr show #{interface} | grep 'inet6 #{ip_address}'"
    end