DNS problem resolving local names

[Chris Green]

I'm running Ubuntu 18.04 with a Draytek 2860n router connecting to the
internet.  The router provides resolution of some LAN addresses for me:-

For example my printer:-

    chris at esprimo$ dig @192.168.1.1 oki

    ; <<>> DiG 9.11.3-1ubuntu1.3-Ubuntu <<>> @192.168.1.1 oki
    ; (1 server found)
    ;; global options: +cmd
    ;; Got answer:
    ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 64099
    ;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0
    ;; WARNING: Message has 3 extra bytes at end

    ;; QUESTION SECTION:
    ;oki.                           IN      A

    ;; ANSWER SECTION:
    oki.                    86400   IN      A       192.168.1.50

    ;; Query time: 0 msec
    ;; SERVER: 192.168.1.1#53(192.168.1.1)
    ;; WHEN: Mon Feb 04 22:49:43 GMT 2019
    ;; MSG SIZE  rcvd: 40

    chris at esprimo$ 

The system is set up with a static IP and has 192.168.1.1 set as the
DNS server:-

    chris at esprimo$ nmcli
    eth0: connected to Wired connection 1
            "Intel 82579LM Gigabit (Lewisville)"
            ethernet (e1000e), 90:1B:0E:06:BC:91, hw, mtu 1500
            ip4 default
            inet4 192.168.1.3/24
            route4 192.168.1.0/24
            route4 169.254.0.0/16
            route4 192.168.20.1/32
            route4 0.0.0.0/0
            inet6 fe80::921b:eff:fe06:bc91/64
            route6 ff00::/8
            route6 fe80::/64
            route6 fe80::/64

    lo: unmanaged
            "lo"
            loopback (unknown), 00:00:00:00:00:00, sw, mtu 65536

    DNS configuration:
            servers: 192.168.1.1
            interface: eth0


But I can't actually connect to my printer by name:-

    chris at esprimo$ ping oki
    ping: oki: Temporary failure in name resolution
    ping: oki.zbmc.eu: Temporary failure in name resolution
    chris at esprimo$ 

Other commands report the same "Temporary failure in name resolution".


This is driving me crazy!  How can I diagnose and resolve the problem?

-- 
Chris Green