Re: [PATCH] ip route: Do not imply pref and ttl-propagate are per nexthop

[Roopa Prabhu <roopa@cumulusnetworks.com>]

On Tue, Feb 25, 2020 at 5:12 AM Donald Sharp <sharpd@cumulusnetworks.com> wrote:
>
> Currently `ip -6 route show` gives us this output:
>
> sharpd@eva ~/i/ip (master)> ip -6 route show
> ::1 dev lo proto kernel metric 256 pref medium
> 4:5::6:7 nhid 18 proto static metric 20
>         nexthop via fe80::99 dev enp39s0 weight 1
>         nexthop via fe80::44 dev enp39s0 weight 1 pref medium
>
> Displaying `pref medium` as the last bit of output implies
> that the RTA_PREF is a per nexthop value, when it is infact
> a per route piece of data.
>
> Change the output to display RTA_PREF and RTA_TTL_PROPAGATE
> before the RTA_MULTIPATH data is shown:
>
> sharpd@eva ~/i/ip (master)> ./ip -6 route show
> ::1 dev lo proto kernel metric 256 pref medium
> 4:5::6:7 nhid 18 proto static metric 20 pref medium
>         nexthop via fe80::99 dev enp39s0 weight 1
>         nexthop via fe80::44 dev enp39s0 weight 1
>
> Signed-off-by: Donald Sharp <sharpd@cumulusnetworks.com>


Acked-by: Roopa Prabhu <roopa@cumulusnetworks.com>


> ---
>  ip/iproute.c | 11 ++++++++---
>  1 file changed, 8 insertions(+), 3 deletions(-)
>
> diff --git a/ip/iproute.c b/ip/iproute.c
> index 93b805c9..07c45169 100644
> --- a/ip/iproute.c
> +++ b/ip/iproute.c
> @@ -933,9 +933,6 @@ int print_route(struct nlmsghdr *n, void *arg)
>         if (tb[RTA_IIF] && filter.iifmask != -1)
>                 print_rta_if(fp, tb[RTA_IIF], "iif");
>
> -       if (tb[RTA_MULTIPATH])
> -               print_rta_multipath(fp, r, tb[RTA_MULTIPATH]);
> -
>         if (tb[RTA_PREF])
>                 print_rt_pref(fp, rta_getattr_u8(tb[RTA_PREF]));
>
> @@ -951,6 +948,14 @@ int print_route(struct nlmsghdr *n, void *arg)
>                                      propagate ? "enabled" : "disabled");
>         }
>
> +       if (tb[RTA_MULTIPATH])
> +               print_rta_multipath(fp, r, tb[RTA_MULTIPATH]);
> +
> +       /* If you are adding new route RTA_XXXX then place it above
> +        * the RTA_MULTIPATH else it will appear that the last nexthop
> +        * in the ECMP has new attributes
> +        */
> +
>         print_string(PRINT_FP, NULL, "\n", NULL);
>         close_json_object();
>         fflush(fp);
> --
> 2.25.0
>