Static routing on Linux (ip route + netplan)

docs/module/routing.md

@@ -22,22 +22,22 @@ This configuration module implements generic routing features:
 The following table describes high-level per-platform support of generic routing features:
 
 | Operating system      | Routing<br>policies | Prefix<br>filters| AS-path<br>filters | BGP<br>communities | Static<br>routes|
-| ------------------ | :-: | :-: | :-: |:-: | :-: |
-| Arista EOS          |  ✅  |  ✅  |  ✅  |  ✅  |
-| Aruba AOS-CX        |  ✅  |  ✅  |  ✅  |  ✅  |
-| Cisco IOSv/IOSvL2   |  ✅  |  ✅  |  ✅  |  ✅  |
-| Cisco IOS-XE[^18v]  |  ✅  |  ✅  |  ✅  |  ✅  |
-| Cumulus Linux       |  ✅  |  ✅  |  ✅  |  ✅  |
-| FRR                 |  ✅  |  ✅  |  ✅  |  ✅  |
-| Nokia SR Linux      |  ✅  |  ✅ [❗](caveats-srlinux) |
-| Nokia SR OS         |  ✅  |
-| VyOS                |  ✅  |  ✅  |  ✅  |  ✅  |
+| ------------------ |:--:|:--:|:--:|:--:|:--:|
+| Arista EOS         | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Aruba AOS-CX       | ✅ | ✅ | ✅ | ✅ |
+| Cisco IOS/XE[^18v] | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Cumulus Linux      | ✅ | ✅ | ✅ | ✅ | ✅ |
+| FRR                | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Linux              | ❌  | ❌  | ❌  | ❌  | ✅ |
+| Nokia SR Linux     |  ✅ |  ✅ [❗](caveats-srlinux) |
+| Nokia SR OS        |  ✅ |
+| VyOS               |  ✅ |  ✅ | ✅ |  ✅  |
 
 ```{tip}
 See [Routing Integration Tests Results](https://release.netlab.tools/_html/coverage.routing) for more details.
 ```
 
-[^18v]: Includes Cisco CSR 1000v, Cisco Catalyst 8000v, Cisco IOS-on-Linux (IOL), and IOL Layer-2 image.
+[^18v]: Includes Cisco IOSv, Cisco IOSvL2, Cisco CSR 1000v, Cisco Catalyst 8000v, Cisco IOS-on-Linux (IOL), and IOL Layer-2 image.
 
 (generic-routing-policies)=
 ## Routing Policies
@@ -101,8 +101,7 @@ You can use these routing policy **match** parameters on devices supported by th
 |---------------------|:--:|:--:|:--:|:--:|
 | Arista EOS          | ✅ | ❌  | ✅ | ✅ |
 | Aruba AOS-CX        | ✅ | ❌  | ✅ | ✅ |
-| Cisco IOSv/IOSvL2   | ✅ | ❌  | ✅ | ✅ |
-| Cisco IOS-XE[^18v]  | ✅ | ❌  | ✅ | ✅ |
+| Cisco IOS/XE[^18v]  | ✅ | ❌  | ✅ | ✅ |
 | Cumulus Linux       | ✅ | ❌  | ✅ | ✅ |
 | FRR                 | ✅ | ❌  | ✅ | ✅ |
 | Nokia SR Linux      | ✅ |
@@ -114,8 +113,7 @@ You can use these routing policy **set** parameters on devices supported by the
 |---------------------|:--:|:--:|:--:|:--:| :--:|
 | Arista EOS          | ✅ | ✅ | ✅ | ✅ | ✅ |
 | Aruba AOS-CX        | ✅ | ✅ | ✅ | ✅ | ✅ |
-| Cisco IOSv/IOSvL2   | ✅ | ✅ | ✅ | ✅ | ✅ |
-| Cisco IOS-XE[^18v]  | ✅ | ✅ | ✅ | ✅ | ✅ |
+| Cisco IOS/XE[^18v]  | ✅ | ✅ | ✅ | ✅ | ✅ |
 | Cumulus Linux       | ✅ | ✅ | ✅ | ✅ | ✅ |
 | FRR                 | ✅ | ✅ | ✅ | ✅ | ✅ |
 | Nokia SR Linux      | ❌  | ✅ | ✅ | ❌  | ❌  |
@@ -128,8 +126,7 @@ The **set.community** attribute can be used to set these BGP communities on supp
 |---------------------|:--:|:--:|:--:|:--:|:--:|
 | Arista EOS          | ✅ | ✅ | ✅ | ✅ | ✅ |
 | Aruba AOS-CX        | ✅ | ❌  | ❌  | ✅ | ✅ |
-| Cisco IOSv/IOSvL2   | ✅ | ❌  | ❌  | ✅ | ❌  |
-| Cisco IOS-XE[^18v]  | ✅ | ❌  | ❌  | ✅ | ❌  |
+| Cisco IOS/XE[^18v]  | ✅ | ❌  | ❌  | ✅ | ❌  |
 | Cumulus Linux       | ✅ | ✅ | ✅ | ✅ | ❌  |
 | FRR                 | ✅ | ✅ | ✅ | ✅ | ❌  |
 | VyOS                | ✅ | ✅ | ✅ | ✅ | ❌  |
@@ -497,8 +494,7 @@ _netlab_ supports static routes on these platforms:
 | Cisco IOS/XE[^18v]  | ✅ | ✅ | ✅ |
 | Cumulus Linux 4.x   | ✅ | ✅ | ✅ |
 | FRR                 | ✅ | ✅ | ✅ |
-
-[^18v]: Includes Cisco IOSv, Cisco IOSvL2, Cisco CSR 1000v, Cisco Catalyst 8000v, Cisco IOS-on-Linux (IOL), and IOL Layer-2 image.
+| Linux               | ✅ |  ❌ |  ❌ |
 
 ### Global Static Routes
 

netsim/ansible/templates/initial/linux/ubuntu.j2

@@ -140,23 +140,25 @@ network:
 SCRIPT
 {% endfor %}
 
-# Add routes to IPv4 address pools pointing to the first neighbor on the first link
-{% for ifdata in interfaces|default([]) if ifdata.gateway is defined %}
-cat <<SCRIPT > /etc/netplan/04-routes-{{ ifdata.ifname }}.yaml
+{% if routing.static|default([]) %}
+# Add IPv4 static routes
+cat <<SCRIPT > /etc/netplan/04-routes.yaml
 network:
   version: 2
   renderer: networkd
   ethernets:
-    {{ ifdata.ifname }}:
+{%   for intf in routing.static|map(attribute='nexthop.intf',default='')|unique if intf %}
+    {{ intf }}:
       routes:
-{%   for name,pool in pools.items()|default({}) %}
-{%     for af,pfx in pool.items() if af == 'ipv4' and name != 'mgmt' and name != 'router_id' %}
-        - to: {{ pfx }}
-          via: {{ ifdata.gateway.ipv4|ipaddr('address') }}
+{%     for sr_entry in routing.static|default([])
+         if 'ipv4' in sr_entry and
+            sr_entry.nexthop.intf|default('') == intf %}
+        - to: {{ sr_entry.ipv4 }}
+          via: {{ sr_entry.nexthop.ipv4 }}
 {%     endfor %}
 {%   endfor %}
 SCRIPT
-{% endfor  %}
+{% endif %}
 
 echo -n 'Starting netplan generate ' && date
 netplan generate

netsim/ansible/templates/initial/linux/vanilla.j2

@@ -46,24 +46,18 @@ ip link set {{ l.ifname }} mtu {{ l.mtu }}
 {% endif %}
 {% endfor %}
 #
-# Add routes to IPv4 address pools pointing to the first neighbor on the first link
+# Add routes to IPv4 address pools pointing to the first usable default gateway
 #
 # If you need anything better, use FRR instead of Linux and start routing (or use IPv6)
 #
-{% for ifdata in interfaces|default([]) if ifdata.gateway is defined %}
-{%   for name,pool in pools.items()|default({}) %}
-{%     for af,pfx in pool.items() if af == 'ipv4' %}
-# {{ name }} prefix: {{ pfx }} local subnet: {{ ifdata.gateway.ipv4|ipaddr('subnet') }}
-{%       if name not in ['mgmt','router_id'] and pfx is string and
-            pfx != ifdata.gateway.ipv4|ipaddr('subnet') %}
+{% for sr_entry in routing.static|default([]) if 'ipv4' in sr_entry %}
+echo "sr_entry: {{ sr_entry }}"
 set +e
-ip route del {{ pfx }} 2>/dev/null
+ip route del {{ sr_entry.ipv4 }} via {{ sr_entry.nexthop.ipv4 }} 2>/dev/null
 set -e
-ip route add {{ pfx }} via {{ ifdata.gateway.ipv4|ipaddr('address') }}
-{%       endif %}
-{%     endfor %}
-{%   endfor %}
-{% endfor  %}
+ip route add {{ sr_entry.ipv4 }} via {{ sr_entry.nexthop.ipv4 }}{{
+  ' dev '+sr_entry.nexthop.intf if 'intf' in sr_entry.nexthop else '' }}
+{% endfor %}
 #
 # Print the final routing table
 ip route

netsim/ansible/templates/routing/linux.j2

@@ -0,0 +1,8 @@
+#!/bin/bash
+{% if routing.static|default([]) %}
+#
+echo "Static routes are configured as part of the initial configuration template"
+echo
+#
+ip route
+{% endif %}

netsim/devices/linux.yml

@@ -9,6 +9,9 @@ features:
       ipv6: true
     server: true
     relay: true
+  routing:
+    static:
+      max_nexthop: 1
 libvirt:
   image: generic/ubuntu2004
   group_vars:

netsim/modules/routing.py

@@ -777,12 +777,7 @@ def resolve_node_nexthop(sr_data: Box, node: Box, topology: Box) -> Box:
 """
 Check whether a VRF static route is valid and supported by the device on which it's used
 """
-def check_VRF_static_route(sr_data: Box, node: Box, topology: Box) -> bool:
-  d_features = devices.get_device_features(node,topology.defaults)
-  sr_features = d_features.get('routing.static')
-  if not isinstance(sr_features,dict):
-    sr_features = data.get_empty_box()
-
+def check_VRF_static_route(sr_data: Box, node: Box, sr_features: Box) -> bool:
   if 'vrf' in sr_data:
     if sr_data.vrf not in node.get('vrfs',{}):
       log.error(
@@ -819,6 +814,10 @@ def check_VRF_static_route(sr_data: Box, node: Box, topology: Box) -> bool:
 
 def check_static_routes(idx: int,o_name: str,node: Box,topology: Box) -> None:
   sr_data = node.routing[o_name][idx]
+  d_features = devices.get_device_features(node,topology.defaults)
+  sr_features = d_features.get('routing.static')
+  if not isinstance(sr_features,dict):
+    sr_features = data.get_empty_box()
 
   if 'pool' in sr_data:
     sr_data = sr_data + extract_af_info(topology.addressing[sr_data.pool])
@@ -845,7 +844,7 @@ def check_static_routes(idx: int,o_name: str,node: Box,topology: Box) -> None:
     return
 
   if 'vrf' in sr_data or 'vrf' in sr_data.nexthop:
-    if not check_VRF_static_route(sr_data,node,topology):
+    if not check_VRF_static_route(sr_data,node,sr_features):
       return
 
   if sr_data.nexthop.get('node',None):
@@ -868,7 +867,7 @@ def check_static_routes(idx: int,o_name: str,node: Box,topology: Box) -> None:
     for af in log.AF_LIST:
       if af not in sr_data:
         continue
-      for nh_entry in sr_data.nexthop.nhlist:
+      for nh_entry in sr_data.nexthop.nhlist[:sr_features.get('max_nexthop',256)]:
         sr_entry = { af: sr_data[af], 'nexthop': nh_entry }
         if 'vrf' in sr_data:
           sr_entry['vrf'] = sr_data.vrf