weave

module
v0.11.1 Latest Latest
Warning

This package is not in the latest version of its module.

Go to latest
Published: Jun 1, 2015 License: Apache-2.0

README

Weave - the Docker network

Build Status Integration Tests Coverage Status

Weave creates a virtual network that connects Docker containers deployed across multiple hosts and enables their automatic discovery.

Weave Virtual Network

Applications use the network just as if the containers were all plugged into the same network switch, with no need to configure port mappings, links, etc. Services provided by application containers on the weave network can be made accessible to the outside world, regardless of where those containers are running. Similarly, existing internal systems can be exposed to application containers irrespective of their location.

Weave Deployment

Weave can traverse firewalls and operate in partially connected networks. Traffic can be encrypted, allowing hosts to be connected across an untrusted network.

With weave you can easily construct applications consisting of multiple containers, running anywhere.

Weave works alongside Docker's existing (single host) networking capabilities, so these can continue to be used by containers.

Installation

Ensure you are running Linux (kernel 3.8 or later) and have Docker (version 1.3.1 or later) installed. Then install weave with

sudo wget -O /usr/local/bin/weave \
  https://github.com/weaveworks/weave/releases/download/latest_release/weave
sudo chmod a+x /usr/local/bin/weave

CoreOS users see here for an example of installing weave using cloud-config.

Weave respects the environment variable DOCKER_HOST, so you can run it locally to control a weave network on a remote host.

Quick Start Screencast

Example

Say you have docker running on two hosts, accessible to each other as $HOST1 and $HOST2, and want to deploy an application consisting of two containers, one on each host.

On $HOST1 run

host1$ weave launch
host1$ C=$(weave run 10.2.1.1/24 -t -i ubuntu)

The first line starts the weave router, in a container. This needs to be done once on each host. The required docker image for the weave router container is downloaded automatically. There is also a weave setup command for downloading this and other images required for weave operation; this is a strictly optional step which is especially useful for automated installation of weave and ensures that any subsequent weave commands do not encounter delays due to image downloading.

The second line runs our application container. We give it an IP address and network, in CIDR notation. weave run invokes docker run -d with all the parameters following the IP address and network. So we could be launching any container this way; here we just take a stock ubuntu container and launch a shell in it. There's also a weave start command, which invokes docker start for starting existing containers.

If our application consists of more than one container on this host we simply launch them with a variation on that second line.

The IP addresses and netmasks can be anything you like, but make sure they don't conflict with any IP ranges in use on the hosts or IP addresses of external services the hosts or containers need to connect to. The same IP range must be used everywhere, and the individual IP addresses must, of course, be unique.

We repeat similar steps on $HOST2...

host2$ weave launch $HOST1
host2$ C=$(weave run 10.2.1.2/24 -t -i ubuntu)

The only difference, apart from the choice of IP address for the application container, is that we tell our weave that it should peer with the weave on $HOST1 (specified as the IP address or hostname, and optional :port, by which $HOST2 can reach it). NB: if there is a firewall between $HOST1 and $HOST2, you must open the weave port (6783 by default; this can be overriden by setting WEAVE_PORT) for TCP and UDP.

Note that we could instead have told the weave on $HOST1 to connect to $HOST2, or told both about each other. Order does not matter here; weave automatically (re)connects to peers when they become available. Also, we can tell weave to connect to multiple peers by supplying multiple addresses, separated by spaces. And we can add peers dynamically.

Now that we've got everything set up, let's see whether our containers can talk to each other...

On $HOST1...

host1$ docker attach $C
root@28841bd02eff:/# ping -c 1 -q 10.2.1.2
PING 10.2.1.2 (10.2.1.2): 48 data bytes
--- 10.2.1.2 ping statistics ---
1 packets transmitted, 1 packets received, 0% packet loss
round-trip min/avg/max/stddev = 1.048/1.048/1.048/0.000 ms

Similarly, on $HOST2...

host2$ docker attach $C
root@f76829496120:/# ping -c 1 -q 10.2.1.1
PING 10.2.1.1 (10.2.1.1): 48 data bytes
--- 10.2.1.1 ping statistics ---
1 packets transmitted, 1 packets received, 0% packet loss
round-trip min/avg/max/stddev = 1.034/1.034/1.034/0.000 ms

So there we have it, two containers on separate hosts happily talking to each other.

Find out more

Contact Us

Found a bug, want to suggest a feature, or have a question? File an issue, or email help@weave.works. When reporting a bug, please include which version of weave you are running, as shown by weave version.

Follow weave on Twitter: @weaveworks.

Read the Weave blog: Weaveblog.

IRC: #weavenetwork

Directories

Path Synopsis
ring
Package ring implements a simple ring CRDT.
Package ring implements a simple ring CRDT.

Jump to

Keyboard shortcuts

? : This menu
/ : Search site
f or F : Jump to
y or Y : Canonical URL