[PATCH perl-rs v5 08/10] fabrics: bgp: enable force_forwarding for ipv6 transit traffic

[Lukas Sichert <l.sichert@proxmox.com>]

In a non-full-mesh BGP-fabric setup, nodes may need to relay traffic
between peers that are not directly connected. This requires forwarding
ipv6 packets between fabric interfaces. With the addition of
'force_forwarding' to the Linux kernel, this can be done without
enabling 'all.forwarding', which disables Router Advertisements.

Configure fabric interfaces with the ifupdown2 ip6-force-forward flag.

Signed-off-by: Lukas Sichert <l.sichert@proxmox.com>
---
 pve-rs/src/bindings/sdn/fabrics.rs | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pve-rs/src/bindings/sdn/fabrics.rs b/pve-rs/src/bindings/sdn/fabrics.rs
index 8413168..864e060 100644
--- a/pve-rs/src/bindings/sdn/fabrics.rs
+++ b/pve-rs/src/bindings/sdn/fabrics.rs
@@ -771,6 +771,7 @@ pub mod pve_rs_sdn_fabrics {
                             writeln!(interfaces, "iface {name} inet manual")?;
                             writeln!(interfaces, "\tip-forward 1")?;
                             writeln!(interfaces, "\tip6-forward 1")?;
+                            writeln!(interfaces, "\tip6-force-forward 1")?;
                             // BGP unnumbered uses RAs to discover peer link-local
                             // addresses. frr listens for them itself, but the kernel
                             // would otherwise install RA-derived routes we don't want.
-- 
2.47.3