Update logic to configure router bgp even without underlay/overlay

python-avd/pyavd/_eos_designs/shared_utils/filtered_tenants.py

@@ -450,3 +450,38 @@ def get_additional_svi_config(svi_config: dict, svi: dict, vrf: dict) -> None:
                     ospf_keys.append({"id": ospf_key["id"], "hash_algorithm": ospf_key.get("hash_algorithm", "sha512"), "key": ospf_key["key"]})
                 if ospf_keys:
                     svi_config.update({"ospf_authentication": ospf_authentication, "ospf_message_digest_keys": ospf_keys})
+
+    def bgp_in_network_services(self: SharedUtils) -> bool:
+        """
+        True if any VRFs are enabled for BGP.
+
+        Used to enable router_bgp even if there is no overlay or underlay routing protocol.
+        """
+        if not self.network_services_l3:
+            return False
+
+        return any(self.bgp_enabled_for_vrf(vrf) for tenant in self.filtered_tenants for vrf in tenant["vrfs"])
+
+    def bgp_enabled_for_vrf(self: SharedUtils, vrf: dict) -> bool:
+        """
+        True if the given VRF should be included under Router BGP.
+
+        - If bgp.enabled is set to True, we will always configure the VRF.
+        - If bgp.enabled is set to False, we will never configure the VRF.
+
+        Otherwise we will autodetect:
+        - If the VRF is part of an overlay we will configure BGP for it.
+        - If any BGP peers are configured we will configure BGP for it.
+        - If uplink type is p2p_vrfs and the vrf is included in uplink VRFs.
+        """
+        if (bgp_enabled := get(vrf, "bgp.enabled")) is not None:
+            return bgp_enabled
+
+        vrf_address_families = [af for af in vrf.get("address_families", ["evpn"]) if af in self.overlay_address_families]
+        return any(
+            [
+                vrf_address_families,
+                vrf["bgp_peers"],
+                (self.uplink_type == "p2p-vrfs" and vrf["name"] in (self.get_switch_fact("uplink_switch_vrfs", required=False) or [])),
+            ]
+        )

python-avd/pyavd/_eos_designs/shared_utils/routing.py

@@ -51,6 +51,7 @@ def bgp(self: SharedUtils) -> bool:
                     self.overlay_routing_protocol in ["ebgp", "ibgp"]
                     and (self.evpn_role in ["client", "server"] or self.mpls_overlay_role in ["client", "server"])
                 )
+                or self.bgp_in_network_services
             )
         )
 

python-avd/pyavd/_eos_designs/structured_config/network_services/router_bgp.py

@@ -140,40 +140,17 @@ def _router_bgp_vrfs(self: AvdStructuredConfigNetworkServices) -> list | None:
 
         for tenant in self.shared_utils.filtered_tenants:
             for vrf in tenant["vrfs"]:
-                # If bgp.enabled is set to True, we will always configure the VRF.
-                # If bgp.enabled is set to False, we will never configure the VRF.
-                # Otherwise we will autodetect:
-                #  - if the VRF is part of an overlay we will configure BGP for it.
-                #  - if any BGP peers are configured we will configure BGP for it.
-                #  - if uplink type is p2p_vrfs and the vrf is included in uplink VRFs.
-
-                if (bgp_enabled := get(vrf, "bgp.enabled")) is False:
+                if not self.shared_utils.bgp_enabled_for_vrf(vrf):
                     continue
 
-                vrf_address_families = [af for af in vrf.get("address_families", ["evpn"]) if af in self.shared_utils.overlay_address_families]
                 vrf_name = vrf["name"]
-                if not any(
-                    [
-                        bgp_enabled,
-                        vrf_address_families,
-                        vrf["bgp_peers"],
-                        (
-                            self.shared_utils.uplink_type == "p2p-vrfs"
-                            and vrf_name in (self.shared_utils.get_switch_fact("uplink_switch_vrfs", required=False) or [])
-                        ),
-                    ]
-                ):
-                    continue
-
                 bgp_vrf = {
                     "name": vrf_name,
-                    # Adding router_id here to avoid reordering structured config for all hosts. TODO: Remove router_id.
-                    "router_id": None,
                     "eos_cli": get(vrf, "bgp.raw_eos_cli"),
                     "struct_cfg": get(vrf, "bgp.structured_config"),
                 }
 
-                if vrf_address_families:
+                if vrf_address_families := [af for af in vrf.get("address_families", ["evpn"]) if af in self.shared_utils.overlay_address_families]:
                     # For EVPN configs get evpn keys and continue after the elif block below.
                     self._update_router_bgp_vrf_evpn_or_mpls_cfg(bgp_vrf, vrf, vrf_address_families)