diff --git a/site/operational-guide/concepts.md b/site/operational-guide/concepts.md index e087fe59..c2584120 100644 --- a/site/operational-guide/concepts.md +++ b/site/operational-guide/concepts.md @@ -6,18 +6,30 @@ This section describes some of the essential concepts with which you will need to be familiar before continuing to the example deployment scenarios. -## Host +The following concepts are described: + + * [Host](#host) + * [Peer](#peer) + * [Peer Discovery](#peer-discovery) + * [Network Partition](#network-partition) + * [IP Address Manager- IPAM](#ip-address-manager) + * [Seeding](#seeding) + * [Consensus](#consensus) + * [Observers](#observers) + * [Persistence](#persistence) + +##Host For the purposes of this documentation a host is an installation of the Linux operating system that is running an instance of the Docker Engine. The host may be executing directly on bare hardware or inside a virtual machine. -## Peer +##Peer A peer is a running instance of Weave Net, typically one per host. -## Peer Name +##Peer Name Weave Net peers are identified by a 48-bit value formatted like an ethernet MAC address, for example, `01:23:45:67:89:ab`. The 'peer @@ -50,14 +62,14 @@ The appropriate strategy for assigning peer names depends on the type and method of your particular deployment and is discussed in more detail below. -## Peer Discovery +##Peer Discovery Peer discovery is a mechanism that allows peers to learn about new Weave Net hosts from existing peers without being explicitly told. Peer discovery is [enabled by default](/site/using-weave/finding-adding-hosts-dynamically.md). -## Network Partition +##Network Partition A network partition is a transient condition whereby some arbitrary subsets of peers are unable to communicate with each other for the @@ -66,7 +78,7 @@ optic line severed. Weave Net is designed to allow peers and their containers to make maximum safe progress under conditions of partition, healing automatically once the partition is over. -## IP Address Manager (IPAM) +##IP Address Manager (IPAM) [IPAM](/site/ipam.md) is the subsystem responsible for dividing up a large contiguous block of IP addresses (known as the IP allocation @@ -77,7 +89,7 @@ When a new network is formed an initial division of the IP allocation range must be made. Two (mutually exclusive) mechanisms with different tradeoffs are provided to perform this task: seeding and consensus. -### Seeding +### Seeding Seeding requires each peer to be told the list of peer names amongst which the address space is to be divided initially. There are some @@ -100,7 +112,7 @@ scenarios: * [Uniform Dynamic Cluster](/site/operational-guide/uniform-dynamic-cluster.md) -### Consensus +###Consensus Alternatively, when a new network is formed for the first time, peers can be configured to co-ordinate amongst themselves to automatically @@ -116,7 +128,7 @@ scenarios: * [Interactive Deployment](/site/operational-guide/interactive.md) * [Uniform Fixed Cluster](/site/operational-guide/uniform-fixed-cluster.md) -### Observers +###Observers Finally, an option is provided to start a peer as an _observer_. Such peers do not require a seed peer name list or an initial peer @@ -130,7 +142,7 @@ scenarios: * [Autoscaling](/site/operational-guide/autoscaling.md) -## Persistence +##Persistence Certain information is remembered between launches of Weave Net (for example across reboots):