Order: 212.54.44.54, 192.168.178.70
-----------------------------------

dhcp reply with tcpdump

    $ sudo tcpdump -i wlp2s0 -vvvnn -s 1500 '(port 67 or port 68)'
    12:58:14.848055 IP (tos 0x0, ttl 128, id 57005, offset 0, flags [none], proto UDP (17), length 328)
        192.168.178.1.67 > 192.168.178.16.68: [udp sum ok] BOOTP/DHCP, Reply, length 300, xid 0xa4e62230, Flags [none] (0x0000)
          Your-IP 192.168.178.16
          Server-IP 192.168.178.1
          Client-Ethernet-Address xx:xx:xx:xx:xx:xx
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: ACK
            Subnet-Mask Option 1, length 4: 255.255.255.0
            Time-Zone Option 2, length 4: 0
            Default-Gateway Option 3, length 4: 192.168.178.1
            TTL Option 23, length 1: 64
            Lease-Time Option 51, length 4: 86400
            Server-ID Option 54, length 4: 192.168.178.1
            Domain-Name-Server Option 6, length 8: 212.54.44.54,192.168.178.70
            END Option 255, length 0
            PAD Option 0, length 0, occurs 13


Order: 192.168.178.70, 212.54.44.54
-----------------------------------

dhcp reply with tcpdump:

    $ sudo tcpdump -i wlp2s0 -vvvnn -s 1500 '(port 67 or port 68)'
    13:11:09.619238 IP (tos 0x0, ttl 128, id 57005, offset 0, flags [none], proto UDP (17), length 328)
        192.168.178.1.67 > 192.168.178.16.68: [udp sum ok] BOOTP/DHCP, Reply, length 300, xid 0x3add588f, Flags [none] (0x0000)
          Your-IP 192.168.178.16
          Server-IP 192.168.178.1
          Client-Ethernet-Address xx:xx:xx:xx:xx:xx
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: ACK
            Subnet-Mask Option 1, length 4: 255.255.255.0
            Time-Zone Option 2, length 4: 0
            Default-Gateway Option 3, length 4: 192.168.178.1
            TTL Option 23, length 1: 64
            Lease-Time Option 51, length 4: 86400
            Server-ID Option 54, length 4: 192.168.178.1
            Domain-Name-Server Option 6, length 8: 192.168.178.70,212.54.44.54
            END Option 255, length 0
            PAD Option 0, length 0, occurs 13


But 212.54.44.54 is always on top
---------------------------------

resolv.conf file after dhcp lease acquired:

    $ cat /etc/resolv.conf
    # This file is managed by systemd-resolved(8). Do not edit.
    #
    # Third party programs must not access this file directly, but
    # only through the symlink at /etc/resolv.conf. To manage
    # resolv.conf(5) in a different way, replace the symlink by a
    # static file or a different symlink.

    nameserver 212.54.44.54
    nameserver 192.168.178.70


Lease information as stored by systemd

    $ cat /run/systemd/netif/leases/2
    # This is private data. Do not parse.
    ADDRESS=192.168.178.16
    NETMASK=255.255.255.0
    ROUTER=192.168.178.1
    SERVER_ADDRESS=192.168.178.1
    NEXT_SERVER=192.168.178.1
    DNS=192.168.178.70 212.54.44.54
    NTP=
    CLIENTID=ffe708d2ba00020000ab11f816004b73b60272