[PATCH manager 3/3] fix #5066: reload networking: flush PROXMOX-SDN iptables chain at reload

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

With the addition of a separate PROXMOX-SDN iptable chain it is now
possible to flush this distinct chain, without affecting unreated
POSTROUTING rules set by the user.

Flush old rules by running 'iptables -t nat -F PROXMOX-SDN' at the end
of the reload_network_config API call, before executing 'ifreload -a'.
The reload then adds the currently valid rules again.

Signed-off-by: Lukas Sichert <l.sichert@proxmox.com>
---
 .codex              | 0
 PVE/API2/Network.pm | 3 +++
 2 files changed, 3 insertions(+)
 create mode 100644 .codex

diff --git a/.codex b/.codex
new file mode 100644
index 00000000..e69de29b
diff --git a/PVE/API2/Network.pm b/PVE/API2/Network.pm
index c5863ca7..a8ec88a4 100644
--- a/PVE/API2/Network.pm
+++ b/PVE/API2/Network.pm
@@ -932,6 +932,9 @@ __PACKAGE__->register_method({
                     print "$2 : $line \n";
                 }
             };
+            PVE::Tools::run_command(['iptables', '-t', 'nat', '-F', 'PROXMOX-SDN'], noerr => 1);
+            PVE::Tools::run_command(['ip6tables', '-t', 'nat', '-F', 'PROXMOX-SDN'],
+                noerr => 1);
             PVE::Tools::run_command(['ifreload', '-a'], errfunc => $err);
 
             if (defined($regenerate_frr)) {
-- 
2.47.3