diff options
| author | David Ahern | 2017-01-18 07:40:36 -0800 |
|---|---|---|
| committer | David S. Miller | 2017-01-19 23:38:51 -0500 |
| commit | a1a22c12060e4b9c52f45d4b3460f614e00162a2 (patch) | |
| tree | 9c1d02cf0de871f96942e95fa5ba873237006a2e /net/ipv6 | |
| parent | dceeab0e5258fccad5dbf95b54821ae4e919e0b6 (diff) | |
net: ipv6: Keep nexthop of multipath route on admin down
IPv6 deletes route entries associated with multipath routes on an
admin down where IPv4 does not. For example:
$ ip ro ls vrf red
unreachable default metric 8192
1.1.1.0/24 metric 64
nexthop via 10.100.1.254 dev eth1 weight 1
nexthop via 10.100.2.254 dev eth2 weight 1
10.100.1.0/24 dev eth1 proto kernel scope link src 10.100.1.4
10.100.2.0/24 dev eth2 proto kernel scope link src 10.100.2.4
$ ip -6 ro ls vrf red
2001:db8:1::/120 dev eth1 proto kernel metric 256 pref medium
2001:db8:2:: dev red proto none metric 0 pref medium
2001:db8:2::/120 dev eth2 proto kernel metric 256 pref medium
2001:db8:11::/120 via 2001:db8:1::16 dev eth1 metric 1024 pref medium
2001:db8:11::/120 via 2001:db8:2::17 dev eth2 metric 1024 pref medium
...
Set link down:
$ ip li set eth1 down
IPv4 retains the multihop route but flags eth1 route as dead:
$ ip ro ls vrf red
unreachable default metric 8192
1.1.1.0/24
nexthop via 10.100.1.16 dev eth1 weight 1 dead linkdown
nexthop via 10.100.2.16 dev eth2 weight 1
10.100.2.0/24 dev eth2 proto kernel scope link src 10.100.2.4
and IPv6 deletes the route as part of flushing all routes for the device:
$ ip -6 ro ls vrf red
2001:db8:2:: dev red proto none metric 0 pref medium
2001:db8:2::/120 dev eth2 proto kernel metric 256 pref medium
2001:db8:11::/120 via 2001:db8:2::17 dev eth2 metric 1024 pref medium
...
Worse, on admin up of the device the multipath route has to be deleted
to get this leg of the route re-added.
This patch keeps routes that are part of a multipath route if
ignore_routes_with_linkdown is set with the dead and linkdown flags
enabling consistency between IPv4 and IPv6:
$ ip -6 ro ls vrf red
2001:db8:2:: dev red proto none metric 0 pref medium
2001:db8:2::/120 dev eth2 proto kernel metric 256 pref medium
2001:db8:11::/120 via 2001:db8:1::16 dev eth1 metric 1024 dead linkdown pref medium
2001:db8:11::/120 via 2001:db8:2::17 dev eth2 metric 1024 pref medium
...
Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/ipv6')
| -rw-r--r-- | net/ipv6/route.c | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/net/ipv6/route.c b/net/ipv6/route.c index 5585c501a540..4b1f0f98a0e9 100644 --- a/net/ipv6/route.c +++ b/net/ipv6/route.c @@ -2711,13 +2711,16 @@ struct arg_dev_net { struct net *net; }; +/* called with write lock held for table with rt */ static int fib6_ifdown(struct rt6_info *rt, void *arg) { const struct arg_dev_net *adn = arg; const struct net_device *dev = adn->dev; if ((rt->dst.dev == dev || !dev) && - rt != adn->net->ipv6.ip6_null_entry) + rt != adn->net->ipv6.ip6_null_entry && + (rt->rt6i_nsiblings == 0 || + !rt->rt6i_idev->cnf.ignore_routes_with_linkdown)) return -1; return 0; @@ -3216,7 +3219,7 @@ static int rt6_fill_node(struct net *net, else rtm->rtm_type = RTN_UNICAST; rtm->rtm_flags = 0; - if (!netif_carrier_ok(rt->dst.dev)) { + if (!netif_running(rt->dst.dev) || !netif_carrier_ok(rt->dst.dev)) { rtm->rtm_flags |= RTNH_F_LINKDOWN; if (rt->rt6i_idev->cnf.ignore_routes_with_linkdown) rtm->rtm_flags |= RTNH_F_DEAD; |