Add EVPN LAG Support

AI-assisted: Claude Code
Signed-off-by: Freerk-Ole Zakfeld <fzakfeld@scaleuptech.com>

Remove .vscode/settings.json

Signed-off-by: Freerk-Ole Zakfeld <fzakfeld@scaleuptech.com>

Rework

Signed-off-by: Freerk-Ole Zakfeld <fzakfeld@scaleuptech.com>

Author: fzakfeld

osism/tasks/conductor/sonic/config_generator.py

@@ -73,6 +73,17 @@ def generate_sonic_config(device, hwsku, device_as_mapping=None, config_version=
     # Get port channel configuration from NetBox first (needed by get_connected_interfaces)
     portchannel_info = detect_port_channels(device)
 
+    # Resolve evpn_system_mac early so it is validated once and passed explicitly later
+    _raw_evpn_mac = device.config_context.get("_evpn_system_mac")
+    evpn_system_mac = (
+        _raw_evpn_mac if isinstance(_raw_evpn_mac, str) and _raw_evpn_mac else None
+    )
+    if _raw_evpn_mac and not evpn_system_mac:
+        logger.warning(
+            f"Device {device.name}: '_evpn_system_mac' in config_context is not a valid string"
+            f" (got {type(_raw_evpn_mac).__name__!r}), ignoring"
+        )
+
     # Get connected interfaces to determine admin_status
     connected_interfaces, connected_portchannels = get_connected_interfaces(
         device, portchannel_info
@@ -274,7 +285,7 @@ def generate_sonic_config(device, hwsku, device_as_mapping=None, config_version=
         config["BREAKOUT_PORTS"].update(breakout_info["breakout_ports"])
 
     # Add port channel configuration
-    _add_portchannel_configuration(config, portchannel_info)
+    _add_portchannel_configuration(config, portchannel_info, evpn_system_mac)
 
     # Add VRF configuration
     _add_vrf_configuration(config, vrf_info, netbox_interfaces)
@@ -2108,17 +2119,20 @@ def _add_vrf_configuration(config, vrf_info, netbox_interfaces):
             )
 
 
-def _add_portchannel_configuration(config, portchannel_info):
+def _add_portchannel_configuration(config, portchannel_info, evpn_system_mac=None):
     """Add port channel configuration from NetBox."""
     if portchannel_info["portchannels"]:
         for pc_name, pc_data in portchannel_info["portchannels"].items():
             # Add PORTCHANNEL configuration
-            config["PORTCHANNEL"][pc_name] = {
+            pc_config = {
                 "admin_status": pc_data["admin_status"],
                 "fast_rate": pc_data["fast_rate"],
                 "min_links": pc_data["min_links"],
                 "mtu": pc_data["mtu"],
             }
+            if pc_data.get("evpn_lag") and evpn_system_mac:
+                pc_config["system_mac"] = evpn_system_mac
+            config["PORTCHANNEL"][pc_name] = pc_config
 
             # Add PORTCHANNEL_INTERFACE configuration to enable IPv6 link-local
             config["PORTCHANNEL_INTERFACE"][pc_name] = {

osism/tasks/conductor/sonic/constants.py

@@ -5,6 +5,9 @@
 # Tag to add AF L2VPN EVPN to BGP neighbor
 BGP_AF_L2VPN_EVPN_TAG = "bgp-af-l2vpn-evpn"
 
+# Tag to enable EVPN Multihoming (evpn-lag mode) on a port channel
+EVPN_LAG_TAG = "evpn-lag"
+
 # Default AS prefix for local ASN calculation
 DEFAULT_LOCAL_AS_PREFIX = 4200
 

osism/tasks/conductor/sonic/interface.py

@@ -7,7 +7,12 @@
 import re
 from loguru import logger
 
-from .constants import PORT_TYPE_TO_SPEED_MAP, HIGH_SPEED_PORTS, PORT_CONFIG_PATH
+from .constants import (
+    PORT_TYPE_TO_SPEED_MAP,
+    HIGH_SPEED_PORTS,
+    PORT_CONFIG_PATH,
+    EVPN_LAG_TAG,
+)
 from .cache import get_cached_device_interfaces
 
 # Global cache for port configurations to avoid repeated file reads
@@ -978,7 +983,7 @@ def detect_port_channels(device):
         # Get all interfaces for the device (using cache)
         interfaces = get_cached_device_interfaces(device.id)
 
-        # First pass: find LAG interfaces
+        # First pass: find LAG interfaces and precompute evpn_lag lookup
         lag_interfaces = []
         for interface in interfaces:
             # Check if this is a LAG interface
@@ -987,6 +992,15 @@ def detect_port_channels(device):
                     lag_interfaces.append(interface)
                     logger.debug(f"Found LAG interface: {interface.name}")
 
+        evpn_lag_by_id = {
+            iface.id: (
+                hasattr(iface, "tags")
+                and iface.tags
+                and any(tag.slug == EVPN_LAG_TAG for tag in iface.tags)
+            )
+            for iface in lag_interfaces
+        }
+
         # Second pass: map members to LAGs
         for interface in interfaces:
             # Check if this interface has a LAG parent
@@ -1044,12 +1058,15 @@ def detect_port_channels(device):
 
                 # Initialize port channel if not exists
                 if portchannel_name not in portchannels:
+                    evpn_lag = evpn_lag_by_id.get(lag_parent.id, False)
+
                     portchannels[portchannel_name] = {
                         "members": [],
                         "admin_status": "up",
                         "fast_rate": "true",
                         "min_links": "1",
                         "mtu": "9100",
+                        "evpn_lag": evpn_lag,
                     }
 
                 # Add member to port channel