如何解决 DDNS 转发问题？

Question

运行 BIND 9.10.3-P4-RedHat-9.10.3-12.P4.fc23 和 DHCP 服务器 4.3.3-P1。 DNS 区域没有报告错误并且似乎可以工作（dig、nslookup、nsupdate、dnssec、rpz 等）。 DHCP 启动时没有任何抱怨，分配 IP，但每个客户端都会出现类似以下内容的日志文件消息：“无法添加从 pc2.blkdiamonds.lan. 到 10.0.2.63 的正向映射”。

我已经阅读了手册页、论坛帖子、dhcp 用户列表和档案，但我无法确定我的配置中有哪些不同之处导致 DHCP 服务器将客户端的转发映射发送回客户端？

任何想法将不胜感激。

DHCP.CONF (partial) is a follows:
default-lease-time 600;
max-lease-time 7200;
ddns-updates on;
update-static-leases on;
use-host-decl-names on;
ddns-update-style interim;
authoritative;
include "/etc/named/_blkdiamonds.ddns.update.key";
log-facility local7;
ping-check true;
ddns-domainname "blkdiamonds.lan.";
ddns-rev-domainname "in-addr.arpa.";
server-identifier roxie.blkdiamonds.lan;
local-address 10.0.2.254;
one-lease-per-client on;
do-forward-updates true;
....
shared-network benu {
    ignore client-updates;
    deny unknown-clients;
    # wr0
    subnet 10.0.2.0 netmask 255.255.255.0 {
        authoritative;
        ignore client-updates;
        deny unknown-clients;
        ddns-domainname "blkdiamonds.lan.";
        ddns-rev-domainname "in-addr.arpa.";
        range 10.0.2.160 10.0.2.167;
        option broadcast-address 10.0.2.255;
        option domain-name-servers 10.0.2.254;
        option ntp-servers 10.0.2.254;
        option routers 10.0.2.254;
        option time-servers 10.0.2.254;

        group {
            host pc2-wifi.blkdiamonds.lan {
                hardware ethernet 88:25:2c:bc:11:1a;
                fixed-address 10.0.2.63;
                ddns-hostname "Roy-fallen-pc2-wifi";
                }
...
Another subnet