From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Ahern Subject: Re: [iproute PATCH] man: ip-route.8: Document nexthop limit Date: Mon, 12 Nov 2018 16:37:48 -0800 Message-ID: References: <20181112222101.9674-1-phil@nwl.cc> Mime-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org To: Phil Sutter , Stephen Hemminger Return-path: Received: from mail-pg1-f193.google.com ([209.85.215.193]:45002 "EHLO mail-pg1-f193.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725991AbeKMKdZ (ORCPT ); Tue, 13 Nov 2018 05:33:25 -0500 Received: by mail-pg1-f193.google.com with SMTP id w3-v6so4802199pgs.11 for ; Mon, 12 Nov 2018 16:37:51 -0800 (PST) In-Reply-To: <20181112222101.9674-1-phil@nwl.cc> Content-Language: en-US Sender: netdev-owner@vger.kernel.org List-ID: On 11/12/18 2:21 PM, Phil Sutter wrote: > diff --git a/man/man8/ip-route.8.in b/man/man8/ip-route.8.in > index a33ce1f0f4006..383178c11331e 100644 > --- a/man/man8/ip-route.8.in > +++ b/man/man8/ip-route.8.in > @@ -589,6 +589,13 @@ argument lists: > route reflecting its relative bandwidth or quality. > .in -8 > > +The internal buffer used in iproute2 limits the maximum number of nexthops to > +be specified in one go. If only a gateway address is given, the current buffer > +size allows for 144 IPv6 nexthops and 253 IPv4 ones. If more are required, they > +may be added to the existing route using > +.B "ip route append" > +command. > + That is not true for IPv4. 'ip ro append' adds a new route after the existing route - an entry that can not be hit unless all of the nexthops in the first route are down. 'ip ro prepend' adds a new entry before the existing one meaning it takes precedence over the existing entries. For IPv6, 'append' and 'prepend' both add new nexthops to the existing entry.