dnsmasq for dual stack SoftEther VPN

dnsmasq.conf

##################################################################################
# SoftEther VPN server dnsmasq.conf
################################################################################## Interface Settings

# If you want dnsmasq to listen for DHCP and DNS requests only on
# specified interfaces (and the loopback) give the name of the
# interface (eg eth0) here.
# Repeat the line for more than one interface.
interface=tap_soft

# If you want dnsmasq to really bind only the interfaces it is listening on,
# uncomment this option. About the only time you may need this is when
# running another nameserver on the same machine.
bind-interfaces

################################################################################## Options

# Uncomment this to enable the integrated DHCP server, you need
# to supply the range of addresses available for lease and optionally
# a lease time. If you have more than one network, you will need to
# repeat this for each network on which you want to supply DHCP
# service.
dhcp-range=192.168.30.10,192.168.30.255,12h

# Override the default route supplied by dnsmasq, which assumes the
# router is the same machine as the one running dnsmasq.
dhcp-option=3,192.168.30.1

# If you don't want dnsmasq to poll /etc/resolv.conf or other resolv
# files for changes and re-read them then uncomment this.
no-poll

# If you don't want dnsmasq to read /etc/resolv.conf or any other
# file, getting its servers from this file instead (see below), then
# uncomment this.
no-resolv

# Disable re-use of the DHCP servername and filename fields as
# extra option space. This makes extra space available in the
# DHCP packet for options but can, rarely, confuse old or broken
# clients. This flag forces "simple and safe" behavior to avoid
# problems in such a case.
dhcp-no-override

# Never forward addresses in the non-routed address spaces.
bogus-priv

# Do router advertisements for all subnets where we're doing DHCPv6
# Unless overridden by ra-stateless, ra-names, et al, the router
# advertisements will have the M and O bits set, so that the clients
# get addresses and configuration from DHCPv6, and the A bit reset, so the
# clients don't use SLAAC addresses.
enable-ra

# Enable DHCPv6. Note that the prefix-length does not need to be specified
# and defaults to 64 if missing/
dhcp-range=::100,::1ff,constructor:tap_soft, 64, 12h

################################################################################## External DNS Servers

# Use this DNS servers for incoming DNS requests = Cloudflare
server=1.1.1.1
server=1.0.0.1

# Use these IPv6 DNS Servers for lookups = Cloudflare
server=2606:4700:4700::1111
server=2606:4700:4700::1001

#########################################

################################################################################## Client DNS Servers

# Let's send these DNS Servers to clients.
# The first IP is the IPv4 address that are already assigned to the tap_soft

# Set IPv4 DNS server for client machines
dhcp-option=option:dns-server,192.168.30.1,1.1.1.1

# Send DHCPv6 option for namservers as the machine running
# dnsmasq and another.
dhcp-option=option6:dns-server,[fc00:0000:2ac:7af1::1],[2606:4700:4700::1111]

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