OK?

diff --git dhcp6leased.8 dhcp6leased.8
index 762fa4344db..c26e3e040e5 100644
--- dhcp6leased.8
+++ dhcp6leased.8
@@ -31,6 +31,15 @@ is an IPv6 dynamic host configuration protocol (DHCPv6) daemon for clients.
 It requests IPv6 prefix delegations from DHCPv6 servers for assignment
 to downstream interfaces.
 .Pp
+DHCPv6 clients are identified by DHCPv6 Unique Identifiers (DUID).
+.Nm
+uses a DUID based on a random Universally Unique Identifier
+(UUID).
+The DUID is stored in
+.Pa /var/db/dhcp6leased/uuid
+If the file does not exist or the UUID is not readable a new, random
+UUID is generated.
+.Pp
 A running
 .Nm
 can be controlled with the
@@ -70,6 +79,8 @@ Default
 configuration file.
 .It Pa /var/db/dhcp6leased/ Ns Aq Ar if
 Interface specific lease files.
+.It Pa /var/db/dhcp6leased/uuid
+DUID to identify this client.
 .El
 .Sh SEE ALSO
 .Xr dhcp6leased.conf 5 ,

-- 
In my defence, I have been left unsupervised.