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docs: agent/basics: minor fixes

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Dan Frost 2014-11-26 13:15:41 +00:00
parent 84ac7fee60
commit 3bbb226e2b
1 changed files with 11 additions and 11 deletions
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website/source/docs/agent/basics.html.markdown
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@ -72,7 +72,7 @@ There are several important components that `consul agent` outputs:
agent. This is also the address other applications can use over [RPC to control Consul](/docs/agent/rpc.html). agent. This is also the address other applications can use over [RPC to control Consul](/docs/agent/rpc.html).
* **Cluster Addr**: This is the address and ports used for communication between * **Cluster Addr**: This is the address and ports used for communication between
Consul agents in a cluster. Every Consul agent in a cluster does not have to Consul agents in a cluster. Not all Consul agents in a cluster have to
use the same port, but this address **MUST** be reachable by all other nodes. use the same port, but this address **MUST** be reachable by all other nodes.
## Stopping an Agent ## Stopping an Agent
@ -105,7 +105,7 @@ this lifecycle is useful to building a mental model of an agent's interactions
with a cluster, and how the cluster treats a node. with a cluster, and how the cluster treats a node.
When an agent is first started, it does not know about any other node in the cluster. When an agent is first started, it does not know about any other node in the cluster.
To discover it's peers, it must _join_ the cluster. This is done with the `join` To discover its peers, it must _join_ the cluster. This is done with the `join`
command or by providing the proper configuration to auto-join on start. Once a node command or by providing the proper configuration to auto-join on start. Once a node
joins, this information is gossiped to the entire cluster, meaning all nodes will joins, this information is gossiped to the entire cluster, meaning all nodes will
eventually be aware of each other. If the agent is a server, existing servers will eventually be aware of each other. If the agent is a server, existing servers will
@ -115,18 +115,18 @@ In the case of a network failure, some nodes may be unreachable by other nodes.
In this case, unreachable nodes are marked as _failed_. It is impossible to distinguish In this case, unreachable nodes are marked as _failed_. It is impossible to distinguish
between a network failure and an agent crash, so both cases are handled the same. between a network failure and an agent crash, so both cases are handled the same.
Once a node is marked as failed, this information is updated in the service catalog. Once a node is marked as failed, this information is updated in the service catalog.
There is some nuance here relating, since this update is only possible if the There is some nuance here since this update is only possible if the servers can
servers can still [form a quorum](/docs/internals/consensus.html). Once the network still [form a quorum](/docs/internals/consensus.html). Once the network recovers,
failure recovers, or a crashed agent restarts, the cluster will repair itself, or a crashed agent restarts, the cluster will repair itself, and unmark
and unmark a node as failed. The health check in the catalog will also be updated a node as failed. The health check in the catalog will also be updated to reflect
to reflect this. this.
When a node _leaves_, it specifies it's intent to do so, and so the cluster When a node _leaves_, it specifies its intent to do so, and so the cluster
marks that node as having _left_. Unlike the _failed_ case, all of the marks that node as having _left_. Unlike the _failed_ case, all of the
services provided by a node are immediately deregistered. If the agent was services provided by a node are immediately deregistered. If the agent was
a server, replication to it will stop. To prevent an accumulation a server, replication to it will stop. To prevent an accumulation
of dead nodes, Consul will automatically reap _failed_ nodes out of the of dead nodes, Consul will automatically reap _failed_ nodes out of the
catalog as well. This is currently done on a non-configurable interval catalog as well. This is currently done on a non-configurable interval of
which defaults to 72 hours. Reaping is similar to leaving, causing all 72 hours. Reaping is similar to leaving, causing all associated services
associated services to be deregistered. to be deregistered.