Fix route_check.py to ignore local p2p IP prefixes

scripts/route_check.py

@@ -444,6 +444,65 @@ def get_interfaces(namespace):
     return sorted(intf)
 
 
+def is_point_to_point_prefix(prefix):
+    """
+    check if a given prefix is a p2p /31 ipv4 prefix or a /126 ipv6 prefix
+    :return sorted list of local p2p IP prefixes
+    """
+    try:
+        network = ipaddress.ip_network(prefix, strict=False)
+        if isinstance(network, ipaddress.IPv4Network) and network.prefixlen == 31:
+            return True
+        if isinstance(network, ipaddress.IPv6Network) and network.prefixlen == 126:
+            return True
+        return False
+    except ValueError:
+        return False
+
+
+def get_local_p2p_ips(namespace):
+    """
+    helper to read p2p local IPs from interface table in APPL-DB.
+    :return sorted list of local p2p IP addresses
+    """
+    db = swsscommon.DBConnector(APPL_DB_NAME, REDIS_TIMEOUT_MSECS, True, namespace)
+    print_message(syslog.LOG_DEBUG, "APPL DB connected for interfaces")
+    tbl = swsscommon.Table(db, 'INTF_TABLE')
+    keys = tbl.getKeys()
+
+    intf = []
+    for k in keys:
+        lst = re.split(':', k.lower(), maxsplit=1)
+        if len(lst) == 1:
+            # No IP address in key; ignore
+            continue
+
+        ip = lst[1]
+
+        if is_point_to_point_prefix(ip):
+            intf.append(ip)
+
+    print_message(syslog.LOG_DEBUG, json.dumps({"APPL_DB_INTF": sorted(intf)}, indent=4))
+    return sorted(intf)
+
+
+def filter_out_local_p2p_ips(namespace, keys):
+    """
+    helper to filter out local p2p IPs
+    :param keys: APPL-DB:ROUTE_TABLE Routes to check.
+    :return keys filtered out of local
+    """
+    rt = []
+    if_tbl_ips = set(get_local_p2p_ips(namespace))
+
+    for k in keys:
+        if k in if_tbl_ips:
+            continue
+        rt.append(k)
+
+    return rt
+
+
 def filter_out_local_interfaces(namespace, keys):
     """
     helper to filter out local interfaces
@@ -818,6 +877,10 @@ def check_routes_for_namespace(namespace):
     # Drop all those for which DEL received
     rt_asic_miss, _ = diff_sorted_lists(rt_asic_miss, deletes)
 
+    # Filter local p2p IPs if any that are reported as missing in APPL_DB
+    if rt_appl_miss:
+        rt_appl_miss = filter_out_local_p2p_ips(namespace, rt_appl_miss)
+
     if rt_appl_miss:
         results["missed_ROUTE_TABLE_routes"] = rt_appl_miss
 

tests/route_check_test_data.py

@@ -1295,4 +1295,63 @@
         },
         RET: -1,
     },
+    "28": {
+        DESCR: "failure case with local p2p IPs in APP_DB",
+        MULTI_ASIC: False,
+        NAMESPACE: [''],
+        ARGS: "route_check -i 15",
+        RET: -1,
+        PRE: {
+            DEFAULTNS: {
+                APPL_DB: {
+                    ROUTE_TABLE: {
+                        "0.0.0.0/0": {"ifname": "portchannel0"},
+                        "10.10.196.12/31": {"ifname": "portchannel0"},
+                        "10.10.196.20/31": {"ifname": "portchannel0"},
+                        "10.10.196.40/31": {"ifname": "portchannel0"},
+                        "90.10.196.32/32": {"ifname": "portchannel0"},
+                        "fc02::78/126": {"ifname": "portchannel0"},
+                        "fc03::2c/126": {"ifname": "portchannel0"},
+                        "10.10.196.30/31": {"ifname": "lo"}
+                    },
+                    INTF_TABLE: {
+                        "PortChannel1013:90.10.196.24/31": {},
+                        "PortChannel1015:10.10.196.12/31": {},
+                        "PortChannel1017:fc03::2c/126": {},
+                        "PortChannel1021:9603:10b0:503:df4::5e/126": {},
+                        "PortChannel1023:9603:10b0:503:df4::5d/126": {},
+                        "PortChannel1024": {}
+                    }
+                },
+                ASIC_DB: {
+                    RT_ENTRY_TABLE: {
+                        ASIC_RT_ENTRY_KEY_PREFIX + "20.10.196.24/32" + ASIC_RT_ENTRY_KEY_SUFFIX: {},
+                        ASIC_RT_ENTRY_KEY_PREFIX + "10.10.196.40/31" + ASIC_RT_ENTRY_KEY_SUFFIX: {},
+                        ASIC_RT_ENTRY_KEY_PREFIX + "3603:10b0:503:df4::5d/128" + ASIC_RT_ENTRY_KEY_SUFFIX: {},
+                        ASIC_RT_ENTRY_KEY_PREFIX + "0.0.0.0/0" + ASIC_RT_ENTRY_KEY_SUFFIX: {}
+                    }
+                }
+            }
+        },
+        RESULT: {
+            DEFAULTNS: {
+                "missed_ROUTE_TABLE_routes": [
+                    "10.10.196.20/31",
+                    "90.10.196.32/32",
+                    "fc02::78/126"
+                ],
+                "missed_INTF_TABLE_entries": [
+                    "10.10.196.12/32",
+                    "90.10.196.24/32",
+                    "9603:10b0:503:df4::5d/128",
+                    "9603:10b0:503:df4::5e/128",
+                    "fc03::2c/128"
+                ],
+                "Unaccounted_ROUTE_ENTRY_TABLE_entries": [
+                    "20.10.196.24/32",
+                    "3603:10b0:503:df4::5d/128"
+                ]
+            }
+        }
+    },
 }