SR-OS: Adjust system intf IPv6 prefix as a device quirk

Author: ipspace

netsim/ansible/templates/initial/sros.j2

@@ -52,15 +52,16 @@
 {% macro ip_addr(v,ip,ifname) %}
 {% set _ip = ip|ipaddr('address') %}
 {% set _pre = ip|ipaddr('prefix') %}
-   ipv{{v}}:
 {% if v=='4' %}
+   ipv4:
     primary:
      address: "{{ _ip }}"
      prefix-length: {{ _pre }}
 {% else %}
+   ipv6:
     address:
     - ipv6-address: "{{ _ip }}"
-      prefix-length: {{ 128 if ifname=='system' else _pre }}
+      prefix-length: {{ _pre }}
 {% endif %}
 {% endmacro %}
 

netsim/devices/sros.py

@@ -62,10 +62,26 @@ def set_port_modes(node: Box) -> None:
     else:
       set_port_mode(t_intf,'access')
 
+def adjust_system_ipv6_prefix(node: Box) -> None:
+  v6lb = node.get('loopback.ipv6',None)
+  if not v6lb:
+    return
+
+  (v6ad,v6pf) = v6lb.split('/')
+  if v6pf != '128':
+    node.loopback.ipv6 = f'{v6ad}/128'
+    report_quirk(
+      text=f'Loopback prefix {v6lb} on node {node.name} was changed to {node.loopback.ipv6}',
+      more_hints=[ f'The IPv6 prefix configured on SR OS system (loopback) interface must be a /128' ],
+      quirk='loopback_ipv6',
+      node=node,
+      category=Warning)
+
 class SROS(_Quirks):
 
   @classmethod
   def device_quirks(self, node: Box, topology: Box) -> None:
+    adjust_system_ipv6_prefix(node)
     set_port_modes(node)
     ipv4_unnumbered(node)
     vrf_route_leaking(node)