[pve-devel] [PATCH pve-network 1/1] zones: evpn: add a default unreachable, to prevent vrf leak

[Alexandre Bruyelles]

From: Alexandre Bruyelles <git at jack.fr.eu.org>

On Linux, when no route is found in a vrf, it somehow fallback
to the default routing table. In our case, that means a leak
from the overlay to the underlay.
Adding a low priority unreachable catch-all route is the way to go, as
per the doc: https://www.kernel.org/doc/Documentation/networking/vrf.txt

Signed-off-by: Alexandre Bruyelles <git at jack.fr.eu.org>
---
 PVE/Network/SDN/Zones/EvpnPlugin.pm | 1 +
 1 file changed, 1 insertion(+)

diff --git a/PVE/Network/SDN/Zones/EvpnPlugin.pm b/PVE/Network/SDN/Zones/EvpnPlugin.pm
index e6ee839..ca000cf 100644
--- a/PVE/Network/SDN/Zones/EvpnPlugin.pm
+++ b/PVE/Network/SDN/Zones/EvpnPlugin.pm
@@ -134,6 +134,7 @@ sub generate_sdn_config {
 	#vrf interface
 	@iface_config = ();
 	push @iface_config, "vrf-table auto";
+	push @iface_config, "post-up ip route add vrf $vrf_iface unreachable default metric 4278198272";
 	push(@{$config->{$vrf_iface}}, @iface_config) if !$config->{$vrf_iface};
 
 	if ($vrfvxlan) {
-- 
2.31.0