VM -- (eth0)RPI(wlan0) -- Router -- ISP
 ^      ^         ^         ^
DHCP  Static     DHCP      GW

# interfaces(5) file used by ifup(8) and ifdown(8)

# Please note that this file is written to be used with dhcpcd
# For static IP, consult /etc/dhcpcd.conf and 'man dhcpcd.conf'

# Include files from /etc/network/interfaces.d:
source-directory /etc/network/interfaces.d

#auto wlan0
iface wlan0 inet dhcp
wpa-ssid FunBox-84A8
wpa-psk 7A73FA25C43563523D7ED99A4D

#auto eth0
allow-hotplug eth0
iface eth0 inet static
        address 192.168.2.1
        netmask 255.255.255.0
        network 192.168.2.0
        broadcast 192.168.2.255

# Generated by iptables-save v1.6.0 on Sun Feb 17 20:01:56 2019
*nat
:PREROUTING ACCEPT [86:11520]
:INPUT ACCEPT [64:8940]
:OUTPUT ACCEPT [71:5638]
:POSTROUTING ACCEPT [37:4255]
-A PREROUTING -d 192.168.1.21/32 -p tcp -m tcp --dport 170 -j DNAT --to-destination 192.168.2.83:22
-A PREROUTING -d 192.168.1.21/32 -p tcp -m tcp --dport 171 -j DNAT --to-destination 192.168.2.83:443
-A PREROUTING -d 192.168.1.21/32 -p tcp -m tcp --dport 3389 -j DNAT --to-destination 192.168.2.66:3389
-A POSTROUTING -o wlan0 -j MASQUERADE
COMMIT
# Completed on Sun Feb 17 20:01:56 2019
# Generated by iptables-save v1.6.0 on Sun Feb 17 20:01:56 2019
*filter
:INPUT ACCEPT [3188:209284]
:FORWARD ACCEPT [25:2740]
:OUTPUT ACCEPT [2306:270630]
-A FORWARD -i wlan0 -o eth0 -m state --state RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i eth0 -o wlan0 -j ACCEPT
COMMIT
# Completed on Sun Feb 17 20:01:56 2019
# Generated by iptables-save v1.6.0 on Sun Feb 17 20:01:56 2019
*mangle
:PREROUTING ACCEPT [55445:38248798]
:INPUT ACCEPT [3188:209284]
:FORWARD ACCEPT [52257:38039514]
:OUTPUT ACCEPT [2306:270630]
:POSTROUTING ACCEPT [54565:38310208]
COMMIT
# Completed on Sun Feb 17 20:01:56 2019
# Generated by iptables-save v1.6.0 on Sun Feb 17 20:01:56 2019
*raw
:PREROUTING ACCEPT [55445:38248798]
:OUTPUT ACCEPT [2306:270630]
COMMIT
# Completed on Sun Feb 17 20:01:56 2019

# A sample configuration for dhcpcd.
# See dhcpcd.conf(5) for details.

# Allow users of this group to interact with dhcpcd via the control socket.
#controlgroup wheel

# Inform the DHCP server of our hostname for DDNS.
hostname

# Use the hardware address of the interface for the Client ID.
clientid
# or
# Use the same DUID + IAID as set in DHCPv6 for DHCPv4 ClientID as per RFC4361.
# Some non-RFC compliant DHCP servers do not reply with this set.
# In this case, comment out duid and enable clientid above.
#duid

# Persist interface configuration when dhcpcd exits.
persistent

# Rapid commit support.
# Safe to enable by default because it requires the equivalent option set
# on the server to actually work.
option rapid_commit

# A list of options to request from the DHCP server.
option domain_name_servers, domain_name, domain_search, host_name
option classless_static_routes
# Most distributions have NTP support.
option ntp_servers
# Respect the network MTU. This is applied to DHCP routes.
option interface_mtu

# A ServerID is required by RFC2131.
require dhcp_server_identifier

# Generate Stable Private IPv6 Addresses instead of hardware based ones
slaac private

# Example static IP configuration:
#interface eth0
#static ip_address=192.168.0.10/24
#static ip6_address=fd51:42f8:caae:d92e::ff/64
#static routers=192.168.0.1
#static domain_name_servers=192.168.0.1 8.8.8.8 fd51:42f8:caae:d92e::1

# It is possible to fall back to a static IP if DHCP fails:
# define static profile
#profile static_eth0
#static ip_address=192.168.1.23/24
#static routers=192.168.1.1
#static domain_name_servers=192.168.1.1

# fallback to static profile on eth0
#interface eth0
#fallback static_eth0

denyinterfaces eth0

host Accountant {
hardware ethernet 10:60:4b:68:03:21;
fixed-address 192.168.2.83;
}

host Accountant1 {
hardware ethernet 00:0c:29:35:95:ed;
fixed-address 192.168.2.66;
}
host Accountant3 {
hardware ethernet 30:85:A9:1B:C4:8B;
fixed-address 192.168.2.70;
}

root@gateway:/home/pi# systemctl restart dhcpcd
Warning: dhcpcd.service changed on disk. Run 'systemctl daemon-reload' to reload units.
Job for dhcpcd.service failed because the control process exited with error code.
See "systemctl status dhcpcd.service" and "journalctl -xe" for details.
root@gateway:/home/pi# systemctl status dhcpcd
● dhcpcd.service - dhcpcd on all interfaces
   Loaded: loaded (/lib/systemd/system/dhcpcd.service; enabled; vendor preset: enabled)
  Drop-In: /etc/systemd/system/dhcpcd.service.d
           └─wait.conf
   Active: failed (Result: exit-code) since Sun 2019-02-17 20:36:42 GMT; 6s ago
  Process: 775 ExecStart=/usr/lib/dhcpcd5/dhcpcd -q -w (code=exited, status=6)

Feb 17 20:36:42 gateway systemd[1]: Starting dhcpcd on all interfaces...
Feb 17 20:36:42 gateway dhcpcd[775]: Not running dhcpcd because /etc/network/interfaces
Feb 17 20:36:42 gateway dhcpcd[775]: defines some interfaces that will use a
Feb 17 20:36:42 gateway dhcpcd[775]: DHCP client or static address
Feb 17 20:36:42 gateway systemd[1]: dhcpcd.service: Control process exited, code=exited status=6
Feb 17 20:36:42 gateway systemd[1]: Failed to start dhcpcd on all interfaces.
Feb 17 20:36:42 gateway systemd[1]: dhcpcd.service: Unit entered failed state.
Feb 17 20:36:42 gateway systemd[1]: dhcpcd.service: Failed with result 'exit-code'.
Warning: dhcpcd.service changed on disk. Run 'systemctl daemon-reload' to reload units.
root@gateway:/home/pi#
root@gateway:/home/pi# systemctl daemon-reload
root@gateway:/home/pi# systemctl status dhcpcd
● dhcpcd.service - dhcpcd on all interfaces
   Loaded: loaded (/lib/systemd/system/dhcpcd.service; enabled; vendor preset: enabled)
  Drop-In: /etc/systemd/system/dhcpcd.service.d
           └─wait.conf
   Active: failed (Result: exit-code) since Sun 2019-02-17 20:36:42 GMT; 1min 23s ago

Feb 17 20:36:42 gateway systemd[1]: Starting dhcpcd on all interfaces...
Feb 17 20:36:42 gateway dhcpcd[775]: Not running dhcpcd because /etc/network/interfaces
Feb 17 20:36:42 gateway dhcpcd[775]: defines some interfaces that will use a
Feb 17 20:36:42 gateway dhcpcd[775]: DHCP client or static address
Feb 17 20:36:42 gateway systemd[1]: dhcpcd.service: Control process exited, code=exited status=6
Feb 17 20:36:42 gateway systemd[1]: Failed to start dhcpcd on all interfaces.
Feb 17 20:36:42 gateway systemd[1]: dhcpcd.service: Unit entered failed state.
Feb 17 20:36:42 gateway systemd[1]: dhcpcd.service: Failed with result 'exit-code'.
root@gateway:/home/pi#

pi@gateway:/etc$ cat os-release
PRETTY_NAME="Raspbian GNU/Linux 9 (stretch)"
NAME="Raspbian GNU/Linux"
VERSION_ID="9"
VERSION="9 (stretch)"
ID=raspbian
ID_LIKE=debian

#auto eth0
allow-hotplug eth0
iface eth0 inet static
        address 192.168.2.1
        netmask 255.255.255.0
        network 192.168.2.0
        broadcast 192.168.2.255