T2898: add ndp-proxy service

VyOS CLI command
  set service ndp-proxy interface eth0 prefix 2001:db8::/64 mode 'static'

Will generate the following NDP proxy configuration

  $ cat /run/ndppd/ndppd.conf
  # autogenerated by service_ndp-proxy.py

  # This tells 'ndppd' how often to reload the route file /proc/net/ipv6_route
  route-ttl 30000

  # This sets up a listener, that will listen for any Neighbor Solicitation
  # messages, and respond to them according to a set of rules
  proxy eth0 {
      # Turn on or off the router flag for Neighbor Advertisements
      router no
      # Control how long to wait for a Neighbor Advertisment message before invalidating the entry (milliseconds)
      timeout 500
      # Control how long a valid or invalid entry remains in the cache (milliseconds)
      ttl 30000

      # This is a rule that the target address is to match against. If no netmask
      # is provided, /128 is assumed. You may have several rule sections, and the
      # addresses may or may not overlap.
      rule 2001:db8::/64 {
          static
      }
  }

1 files changed, 6 insertions, 0 deletions

diff --git a/op-mode-definitions/monitor-log.xml.in b/op-mode-definitions/monitor-log.xml.in
index 3a8118dcb..c03ec4cce 100644
--- a/op-mode-definitions/monitor-log.xml.in
+++ b/op-mode-definitions/monitor-log.xml.in
@@ -120,6 +120,12 @@
             </properties>
             <command>journalctl --no-hostname --boot --follow --dmesg</command>
           </leafNode>
+          <leafNode name="ndp-proxy">
+            <properties>
+              <help>Monitor last lines of Neighbor Discovery Protocol (NDP) Proxy</help>
+            </properties>
+            <command>journalctl --no-hostname --boot --follow --unit ndppd.service</command>
+          </leafNode>
           <leafNode name="nhrp">
             <properties>
               <help>Monitor last lines of Next Hop Resolution Protocol log</help>