Configure Networking

From Alpine Linux
Revision as of 05:18, 14 August 2010 by Mattx86 (talk | contribs) ("quick post" to get the network configuration page started)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
This material is work-in-progress ...

Do not follow instructions here until this notice is removed.
(Last edited by Mattx86 on 14 Aug 2010.)

This page will assist you in setting up basic networking on Alpine Linux.

Note: You must be logged in as root in order to perform the actions on this page.

Setting System Hostname

To set the system hostname, do something like the following:

echo "hostname.domain.com" > /etc/hostname

To activate the change, do the following:

hostname -F /etc/hostname

Tip: From here, you can skip to the IPv4 DHCP section if you want an Automatic IP (DHCP). Otherwise, if you are going for a Static IP configuration, please continue below.
Note: Does DHCP provide the DNS servers, or do they need to be added manually? This needs to be tested and documented here.

It's also a good idea to add the hostname to the /etc/hosts file, e.g.:

127.0.0.1       localhost.localdomain   localhost
192.168.1.150   hostname.domain.com   hostname

Where:

  • 192.168.1.150 is the static IP address (IPv4) of the Alpine Linux machine.
  • hostname.domain.com is the FQDN (hostname) we set above.
  • hostname is the just the host portion from the FQDN we set above.

Configuring DNS

For simple DNS resolution, do something like the following:

echo "nameserver 8.8.8.8" > /etc/resolv.conf echo "nameserver 8.8.4.4" >> /etc/resolv.conf

The above example uses Google's Public DNS servers.

Loopback Configuration

Tip: It's a good idea (read: required) that you configure loopback.

To configure loopback, add the following to a new file /etc/network/interfaces:

auto lo
iface lo inet loopback

IPv4 Configuration

DHCP (Automatic Configuration)

Note: DHCP configuration details pending.

Static IPv4

As an example, to configure eth0 for a static IPv4 address, add the following to /etc/network/interfaces:

auto eth0
iface eth0 inet static
        address 192.168.1.150
        netmask 255.255.255.0
        gateway 192.168.1.1

IPv6 Configuration

Loading the ipv6 Kernel Module

In order to use IPv6 on Alpine Linux, you must first load the ipv6 kernel module.

To load it manually for the first time, run:

modprobe ipv6

Now, to set it to load on boot from now on, run:

echo "ipv6" >> /etc/modules

Now you are ready to configure Alpine Linux for IPv6.

Stateless Address Autoconfiguration

Note: Stateless address autoconfiguration details pending.

Static IPv6

As an example, to configure eth0 for a static IPv6 address, add the following to /etc/network/interfaces:

Tip: Be sure that you have one auto eth0 definition in your /etc/network/interfaces file, if not already. See the Static IPv4 configuration above.
iface eth0 inet6 static
        address 2001:470:ffff:ff::2
        netmask 64
        gateway 2001:470:ffff:ff::1

Activating Changes and Testing Connectivity

Changes made to /etc/network/interfaces can be activated by running:

/etc/init.d/networking restart

If you did not get any errors, you can now test that networking is configured properly by attempting to ping out:

ping www.google.com

PING www.l.google.com (74.125.47.103) 56(84) bytes of data.
64 bytes from yw-in-f103.1e100.net (74.125.47.103): icmp_seq=1 ttl=48 time=58.5 ms
64 bytes from yw-in-f103.1e100.net (74.125.47.103): icmp_seq=2 ttl=48 time=56.4 ms
64 bytes from yw-in-f103.1e100.net (74.125.47.103): icmp_seq=3 ttl=48 time=57.0 ms
64 bytes from yw-in-f103.1e100.net (74.125.47.103): icmp_seq=4 ttl=48 time=60.2 ms
^C
--- www.l.google.com ping statistics ---
4 packets transmitted, 4 received, 0% packet loss, time 3007ms
rtt min/avg/max/mdev = 56.411/58.069/60.256/1.501 ms

For an IPv6 traceroute (traceroute6), you will first need to install the iputils package:

apk add iputils

Then run traceroute6:

traceroute6 ipv6.google.com

traceroute to ipv6.l.google.com (2001:4860:8009::67) from 2001:470:ffff:ff::2, 30 hops max, 16 byte packets
 1  2001:470:ffff:ff::1 (2001:470:ffff:ff::1)  3.49 ms  0.62 ms  0.607 ms
 2  *  *  *
 3  *  *  *
 4  pr61.iad07.net.google.com (2001:504:0:2:0:1:5169:1)  134.313 ms  95.342 ms  88.425 ms
 5  2001:4860::1:0:9ff (2001:4860::1:0:9ff)  100.759 ms  100.537 ms  89.907 ms
 6  2001:4860::1:0:5db (2001:4860::1:0:5db)  115.563 ms  102.946 ms  106.191 ms
 7  2001:4860::2:0:a7 (2001:4860::2:0:a7)  101.754 ms  100.475 ms  100.512 ms
 8  2001:4860:0:1::c3 (2001:4860:0:1::c3)  99.272 ms  111.989 ms  99.835 ms
 9  yw-in-x67.1e100.net (2001:4860:8009::67)  101.545 ms  109.675 ms  99.431 ms