Re: [iproute PATCH] man: ip-route.8: Document nexthop limit

[Phil Sutter <phil@nwl.cc>]

Hi David,

On Mon, Nov 12, 2018 at 04:37:48PM -0800, David Ahern wrote:
> 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.

Oh, thanks for clarifying. I'll follow-up with a fixed version.

> For IPv6, 'append' and 'prepend' both add new nexthops to the existing
> entry.

'ip route prepend' is not even documented. :(

Thanks, Phil