Raspberry Pi 4 as a router with ufw rules
Raspberry Pi 4 as a basic "router" with ufw rules.
requirements¶
- update rpi
apt update && apt upgrade -y
apt autoremove -y
apt install ufw
## useful
apt install dnsutils
- raspberry pi 4 disable
ipv6at boot
vim /boot/cmdline.txt and add ipv6.disable=1 to the end of the line
example
console=tty1 root=PARTUUID=xxxxXXxx-xx rootfstype=ext4 fsck.repair=yes rootwait ipv6.disable=1
- vim
/etc/default/ufw
DEFAULT_FORWARD_POLICY="ACCEPT"
- cat /etc/sysctl.d/local.conf
net.ipv4.ip_forward=1
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
net.ipv6.conf.lo.disable_ipv6 = 1
raspberry pi 4 nat with ufw¶
- vim
/etc/ufw/before.rules
(...)
#------------------------------------------------------------------------
## sources
## https://gist.github.com/kimus/9315140
## https://www.server-world.info/en/note?os=Ubuntu_22.04&p=ufw&f=2
#
# add to the end
# NAT
*nat
-F
:POSTROUTING ACCEPT [0:0]
# Forward traffic through wlan0
-A POSTROUTING -s 192.168.0.0/24 -o wlan0 -j MASQUERADE
# don't delete the 'COMMIT' line or these nat table rules won't
# be processed
COMMIT
sample of basic ufw rules¶
-
eth0 - "internal" network with static IP
- metric 300, for lower priority for default gw
-
wlan0 - "external" network with DHCP
- metric 200, for default gw priority
## in routes - FROM and TO rules
ufw allow from 192.168.0.0/24 to 192.168.0.0/24 port 22 proto tcp
## out rules
ufw allow out on wlan0 from 192.168.0.0/24 to 94.140.14.15 port 53 proto udp
ufw allow out on wlan0 from 192.168.0.0/24 to 94.140.14.15 port 53 proto udp
ufw allow out on eth0 from 192.168.0.0/24 to 94.140.14.15 port 53 proto udp
ufw allow out on eth0 from 192.168.0.0/24 to 94.140.14.15 port 53 proto udp
ufw allow out on wlan0 from 192.168.0.0/24 to any port 443 proto tcp
ufw allow out on eth0 from 192.168.0.0/24 to any port 443 proto tcp
ufw allow out from 192.168.0.0/24 to any port 443 proto tcp
ufw allow out from 192.168.0.0/24 to any port 80 proto tcp
## enable ufw logging
ufw logging on
other usefull ufw commands¶
# ufw reset
ufw disable
ufw enable
ufw status numbered
ufw delete RUL_NUM
raspberry pi 4 static IP, dhcp and gateway metrics¶
- cat
/etc/dhcpcd.conf | egrep -v '^#|^$'
hostname
clientid
persistent
option rapid_commit
option domain_name_servers, domain_name, domain_search, host_name
option classless_static_routes
option interface_mtu
require dhcp_server_identifier
slaac private
interface wlan0
metric 200
static domain_name_servers=94.140.14.15 94.140.15.16
interface eth0
domain feijaouk.local
search feijaouk.local
metric 300
static ip_address=192.168.0.4/24
static routers=192.168.0.1
static domain_name_servers=94.140.14.15 94.140.15.16
raspberry pi 4 - verify the dns upstream servers¶
resolvconf -l
Happy learning,
2023-06-09-raspberry-pi-4-as-a-router-with-ufw-rules.md