From eefcc888dc4479aad54bbf710b9e5768666c072a Mon Sep 17 00:00:00 2001
From: Tim Wilkinson <tim.j.wilkinson@gmail.com>
Date: Wed, 1 Feb 2023 22:38:17 -0800
Subject: [PATCH] Filter out non-routable ARP entries which confuse LQM

---
 files/usr/local/bin/mgr/lqm.lua | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/files/usr/local/bin/mgr/lqm.lua b/files/usr/local/bin/mgr/lqm.lua
index 2735884a..238e8f6b 100755
--- a/files/usr/local/bin/mgr/lqm.lua
+++ b/files/usr/local/bin/mgr/lqm.lua
@@ -362,18 +362,22 @@ function lqm()
         for mac, entry in pairs(arps)
         do
             if entry.Device:match("%.2$") or entry.Device:match("^br%-dtdlink") then
-                stations[#stations + 1] = {
-                    type = "DtD",
-                    device = entry.Device,
-                    signal = nil,
-                    ip = entry["IP address"],
-                    mac = mac:upper(),
-                    tx_packets = 0,
-                    tx_fail = 0,
-                    tx_retries = 0,
-                    tx_bitrate = 0,
-                    rx_bitrate = 0
-                }
+                -- Sometimes we find arp entries are not routable. Filter them out early.
+                local rt = ip.route(entry["IP address"])
+                if rt and tostring(rt.gw) == entry["IP address"] then
+                    stations[#stations + 1] = {
+                        type = "DtD",
+                        device = entry.Device,
+                        signal = nil,
+                        ip = entry["IP address"],
+                        mac = mac:upper(),
+                        tx_packets = 0,
+                        tx_fail = 0,
+                        tx_retries = 0,
+                        tx_bitrate = 0,
+                        rx_bitrate = 0
+                    }
+                end
             end
         end