From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: Maximum MPLS labels on Linux network stack Date: Wed, 3 May 2017 12:14:09 -0600 Message-ID: <5a408c23-d3e2-aa3e-4574-82521b2255b0@gmail.com> References: <149211493832787@web33j.yandex.ru> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit To: =?UTF-8?B?0JDQu9C10LrRgdC10Lkg0JHQvtC70LTRi9GA0LXQsg==?= , netdev@vger.kernel.org Return-path: Received: from mail-pf0-f182.google.com ([209.85.192.182]:36666 "EHLO mail-pf0-f182.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752660AbdECSOO (ORCPT ); Wed, 3 May 2017 14:14:14 -0400 Received: by mail-pf0-f182.google.com with SMTP id q66so16266893pfi.3 for ; Wed, 03 May 2017 11:14:13 -0700 (PDT) In-Reply-To: <149211493832787@web33j.yandex.ru> Sender: netdev-owner@vger.kernel.org List-ID: On 5/3/17 11:33 AM, Алексей Болдырев wrote: > I watched one forum, there is listed in the properties of one license for Cisco, it says: > > Layer 3 VPN • Multi-VRF CE (VRF-lite); requires IP Services Feature license > • MPLS VPN; requires Advanced IP Feature license > • 26 VRFs There is no direct limit on the number of VRFs the kernel allows you to create. There are indirect ones -- total memory in the system and limits such as /proc/sys/net/ipv6/route/max_size. By increasing the latter I have created 4k VRFs in a system. > • 8192 MPLS labels > > Especially interested in the figure 8192 MPLS Labels. 8192 labels added in one pass is absurd. There is no reason to support such a number. With the latest version of the MPLS stack in the kernel you can add up to 30 labels in a single route. If you want more you have to either recirculate the packet using routes or recompile the kernel and increase the memory limit and the number of labels limit. > > As I understand it, is it either a limit on the number of labels on the stack or the total number of labels? > > In Linux, for example, you can specify a common col- lection of labels through /proc/sys/net/mpls/platforms_labels that just allocates the size of an array which dictates the max label number for that namespace. The array needs to be converted to a hash table at some point. > > Also I would like to know if the openvswitch has a limit of 3 tags in the stack or the total number of MPLS labels that can send? > someone familiar with OVS needs to answer that.