Weave

Weave 2.0.1 is supported by kubespray

Weave uses consensus mode (default mode) and seed mode.

Consensus mode is best to use on static size cluster and seed mode is best to use on dynamic size cluster

Weave encryption is supported for all communication

  • To use Weave encryption, specify a strong password (if no password, no encryption)
  1. # In file ./inventory/sample/group_vars/k8s-cluster.yml
  2. weave_password: EnterPasswordHere

This password is used to set an environment variable inside weave container.

Weave is deployed by kubespray using a daemonSet

  • Check the status of Weave containers
  1. # From client
  2. kubectl -n kube-system get pods | grep weave
  3. # output
  4. weave-net-50wd2                       2/2       Running   0          2m
  5. weave-net-js9rb                       2/2       Running   0          2m

There must be as many pods as nodes (here kubernetes have 2 nodes so there are 2 weave pods).

  • Check status of weave (connection,encryption …) for each node
  1. # On nodes
  2. curl http://127.0.0.1:6784/status
  3. # output on node1
  4. Version: 2.0.1 (up to date; next check at 2017/08/01 13:51:34)
  6.         Service: router
  7.        Protocol: weave 1..2
  8.            Name: fa:16:3e:b3:d6:b2(node1)
  9.      Encryption: enabled
  10.   PeerDiscovery: enabled
  11.         Targets: 2
  12.     Connections: 2 (1 established, 1 failed)
  13.           Peers: 2 (with 2 established connections)
  14.  TrustedSubnets: none
  16.         Service: ipam
  17.          Status: ready
  18.           Range: 10.233.64.0/18
  19.   DefaultSubnet: 10.233.64.0/18
  • Check parameters of weave for each node
  1. # On nodes
  2. ps -aux | grep weaver
  3. # output on node1 (here its use seed mode)
  4. root      8559  0.2  3.0 365280 62700 ?        Sl   08:25   0:00 /home/weave/weaver --name=fa:16:3e:b3:d6:b2 --port=6783 --datapath=datapath --host-root=/host --http-addr=127.0.0.1:6784 --status-addr=0.0.0.0:6782 --docker-api= --no-dns --db-prefix=/weavedb/weave-net --ipalloc-range=10.233.64.0/18 --nickname=node1 --ipalloc-init seed=fa:16:3e:b3:d6:b2,fa:16:3e:f0:50:53 --conn-limit=30 --expect-npc 192.168.208.28 192.168.208.19

Consensus mode (default mode)

This mode is best to use on static size cluster

Seed mode

This mode is best to use on dynamic size cluster

The seed mode also allows multi-clouds and hybrid on-premise/cloud clusters deployement.

  • Switch from consensus mode to seed mode
  1. # In file ./inventory/sample/group_vars/k8s-cluster.yml
  2. weave_mode_seed: true

These two variables are only used when weave_mode_seed is set to true (/!\ do not manually change these values)

  1. # In file ./inventory/sample/group_vars/k8s-cluster.yml
  2. weave_seed: uninitialized
  3. weave_peers: uninitialized

The first variable, weave_seed, contains the initial nodes of the weave network

The second variable, weave_peers, saves the IPs of all nodes joined to the weave network

These two variables are used to connect a new node to the weave network. The new node needs to know the firsts nodes (seed) and the list of IPs of all nodes.

To reset these variables and reset the weave network set them to uninitialized