From bc971c97c471bf175792befe818e89f4e81343e4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?J=C3=B6rg=20Thalheim?= Date: Sat, 8 Feb 2014 20:35:02 +0100 Subject: [PATCH] blog post internet sharing --- ...d-ipv6-on-archlinux-using-dnsmasq.markdown | 43 +++++++++++++++++++ .../code/share-internet/dnsmasq.conf | 7 +++ .../code/share-internet/dnsmasq.conf.dhcp | 10 +++++ .../code/share-internet/share-internet | 4 ++ .../share-internet/share-internet.service | 27 ++++++++++++ 5 files changed, 91 insertions(+) create mode 100644 source/_posts/2014-02-08-internet-sharing-ipv4-and-ipv6-on-archlinux-using-dnsmasq.markdown create mode 100644 source/downloads/code/share-internet/dnsmasq.conf create mode 100644 source/downloads/code/share-internet/dnsmasq.conf.dhcp create mode 100644 source/downloads/code/share-internet/share-internet create mode 100644 source/downloads/code/share-internet/share-internet.service diff --git a/source/_posts/2014-02-08-internet-sharing-ipv4-and-ipv6-on-archlinux-using-dnsmasq.markdown b/source/_posts/2014-02-08-internet-sharing-ipv4-and-ipv6-on-archlinux-using-dnsmasq.markdown new file mode 100644 index 0000000..24d0a31 --- /dev/null +++ b/source/_posts/2014-02-08-internet-sharing-ipv4-and-ipv6-on-archlinux-using-dnsmasq.markdown @@ -0,0 +1,43 @@ +--- +layout: post +title: "Internet sharing (ipv4 and ipv6) on archlinux using dnsmasq" +date: 2014-02-08 20:02:22 +0100 +comments: true +categories: +- arch +- dhcp +- ipv6 router advertisement +--- + +A guide to connect with a different machine using a ethernet cable for +internet sharing or just transferring files: + +1. Install dnsmasq and iproute2 + + $ pacman -S dnsmasq iproute2 + +2. Copy over the configuration files at the end of the article and edit the + */etc/conf.d/share-internet* to match your network setup. + +3. Start the sharing service with systemd + + $ sudo systemctl start internet-sharing.service + +After that the other machine can connect via dhcp. It will get an ipv4 +address from the **10.20.0.0/24** subnet and a ipv6 address from the **fd21:30c2:dd2f::** +subnet. Your host will be reachable via **10.20.0.1** or **fd21:30c2:dd2f::1**. +Thanks to ipv6 router advertising, an AAAA record for each host is automatically set based on the hostname. +This means if your hostname is *foo*, all members of the network can just connect +to it using the address *foo*. You should disable the share-internet.service, if +you don't need it. Otherwise you might mess up network setups, if you connect to a +network with the device on which the dhcp service is running. + +Happy networking! + +{% include_code /etc/conf.d/share-internet lang:bash share-internet/share-internet %} + +{% include_code /etc/systemd/system/share-internet.service lang:ini share-internet/share-internet.service %} + +{% include_code /etc/dnsmasq.conf lang:ini share-internet/dnsmasq.conf %} + +{% include_code /etc/dnsmasq.conf.dhcp lang:bash share-internet/dnsmasq.conf.dhcp %} diff --git a/source/downloads/code/share-internet/dnsmasq.conf b/source/downloads/code/share-internet/dnsmasq.conf new file mode 100644 index 0000000..5a01156 --- /dev/null +++ b/source/downloads/code/share-internet/dnsmasq.conf @@ -0,0 +1,7 @@ +# google as an upstream dns server +server=8.8.8.8 +server=8.8.4.4 +no-resolv +cache-size=2000 + +#conf-file=/etc/dnsmasq.conf.dhcp diff --git a/source/downloads/code/share-internet/dnsmasq.conf.dhcp b/source/downloads/code/share-internet/dnsmasq.conf.dhcp new file mode 100644 index 0000000..5f3d7c4 --- /dev/null +++ b/source/downloads/code/share-internet/dnsmasq.conf.dhcp @@ -0,0 +1,10 @@ +# no need to modify +# ingoing and outgoing device will be set by the systemd service +interface=enp0s25 +no-dhcp-interface=wlp3s0 +dhcp-range=10.20.0.100,10.20.0.199,infinite +dhcp-option=3,10.20.0.1 # router +dhcp-option=5,10.20.0.1 # dns +dhcp-option=42,10.20.0.1 # ntp +dhcp-range=fd21:30c2:dd2f::,ra-stateless,ra-names,infinite +enable-ra diff --git a/source/downloads/code/share-internet/share-internet b/source/downloads/code/share-internet/share-internet new file mode 100644 index 0000000..755cb48 --- /dev/null +++ b/source/downloads/code/share-internet/share-internet @@ -0,0 +1,4 @@ +# Network device where other hosts are connect to, ex: eth0 +INTERNAL_DEVICE="enp0s25" +# Device which has internet access, ex: wlan0 or usb0 +EXTERNAL_DEVICE="wlp3s0" diff --git a/source/downloads/code/share-internet/share-internet.service b/source/downloads/code/share-internet/share-internet.service new file mode 100644 index 0000000..3d78b3a --- /dev/null +++ b/source/downloads/code/share-internet/share-internet.service @@ -0,0 +1,27 @@ +[Unit] +Description='share internet' + +[Service] +Type=oneshot +EnvironmentFile=/etc/conf.d/share-internet +RemainAfterExit=yes +ExecStart=/usr/bin/sed -ie 's!^#conf-file=/etc/dnsmasq\.conf\.dhcp!conf-file=/etc/dnsmasq.conf.dhcp!' /etc/dnsmasq.conf +ExecStart=/usr/bin/sed -ie 's/^interface=[[:alnum:]]+/interface=$INTERNAL_DEVICE/' /etc/dnsmasq.conf.dhcp +ExecStart=/usr/bin/sed -ie 's/^no-dhcp-interface=[[:alnum:]]+/no-dhcp-interface=$EXTERNAL_DEVICE/' /etc/dnsmasq.conf.dhcp +ExecStart=/usr/bin/iptables -t nat -A POSTROUTING -o $EXTERNAL_DEVICE -j MASQUERADE +ExecStart=/usr/bin/ip6tables -t nat -A POSTROUTING -o $EXTERNAL_DEVICE -j MASQUERADE +ExecStart=/usr/bin/sysctl -w net.ipv4.ip_forward=1 net.ipv6.conf.all.forwarding=1 +ExecStart=/usr/bin/ip addr add 10.20.0.1/24 dev $INTERNAL_DEVICE +ExecStart=/usr/bin/ip addr add fd21:30c2:dd2f::1/64 dev $INTERNAL_DEVICE +ExecStart=/usr/bin/systemctl restart dnsmasq + +ExecStop=/usr/bin/ip addr del 10.20.0.1/24 dev $INTERNAL_DEVICE +ExecStop=/usr/bin/ip addr del fd21:30c2:dd2f::1/64 dev $INTERNAL_DEVICE +ExecStop=/usr/bin/sysctl -w net.ipv4.ip_forward=0 net.ipv6.conf.all.forwarding=0 +ExecStop=/usr/bin/iptables -t nat -D POSTROUTING -o $EXTERNAL_DEVICE -i $INTERNAL_DEVICE -j MASQUERADE +ExecStop=/usr/bin/ip6tables -t nat -D POSTROUTING -o $EXTERNAL_DEVICE -i $INTERNAL_DEVICE -j MASQUERADE +ExecStop=/usr/bin/sed -ie 's!^conf-file=/etc/dnsmasq\.conf\.dhcp!#conf-file=/etc/dnsmasq.conf.dhcp!' /etc/dnsmasq.conf +ExecStop=/usr/bin/systemctl restart dnsmasq + +[Install] +WantedBy=multi-user.target