# File lib/specinfra/command/linux/base/ip6tables.rb, line 3
    def check_has_rule(rule, table=nil, chain=nil)
      cmd = "ip6tables"
      cmd += " -t #{escape(table)}" if table
      cmd += " -S"
      cmd += " #{escape(chain)}" if chain
      cmd += " | grep -- #{escape(rule)}"
      cmd += " || ip6tables-save"
      cmd += " -t #{escape(table)}" if table
      cmd += " | grep -- #{escape(rule)}"
      cmd
    end