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---
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layout: docs
page_title: Gossip Protocol
sidebar_title: Gossip Protocol
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description: |-
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Nomad uses a gossip protocol to manage membership. All of this is provided
through the use of the Serf library.
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---
# Gossip Protocol
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Nomad uses a [gossip protocol](https://en.wikipedia.org/wiki/Gossip_protocol)
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to manage membership. This is provided through the use of the [Serf library](https://www.serf.io/).
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The gossip protocol used by Serf is based on
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["SWIM: Scalable Weakly-consistent Infection-style Process Group Membership Protocol"](https://www.cs.cornell.edu/projects/Quicksilver/public_pdfs/SWIM.pdf),
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with a few minor adaptations. There are more details about [Serf's protocol here](https://www.serf.io/docs/internals/gossip.html).
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~> **Advanced Topic!** This page covers technical details of
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the internals of Nomad. You do not need to know these details to effectively
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operate and use Nomad. These details are documented here for those who wish
to learn about them without having to go spelunking through the source code.
## Gossip in Nomad
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Nomad makes use of a single global WAN gossip pool that all servers participate in.
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Membership information provided by the gossip pool allows servers to perform cross region
requests. The integrated failure detection allows Nomad to gracefully handle an entire region
losing connectivity, or just a single server in a remote region. The gossip protocol
is also used to detect servers in the same region to perform automatic clustering
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via the [consensus protocol](/docs/internals/consensus).
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All of these features are provided by leveraging [Serf](https://www.serf.io/). It
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is used as an embedded library to provide these features. From a user perspective,
this is not important, since the abstraction should be masked by Nomad. It can be useful
however as a developer to understand how this library is leveraged.
