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---
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layout: "docs"
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page_title: "Frequently Asked Questions"
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sidebar_current: "docs-faq"
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description: |-
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Frequently asked questions and answers for Nomad
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---
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# Frequently Asked Questions
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## Q: What is Checkpoint? / Does Nomad call home?
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2016-01-14 03:10:08 +00:00
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Nomad makes use of a HashiCorp service called [Checkpoint](https://checkpoint.hashicorp.com)
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which is used to check for updates and critical security bulletins.
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Only anonymous information, which cannot be used to identify the user or host, is
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sent to Checkpoint. An anonymous ID is sent which helps de-duplicate warning messages.
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This anonymous ID can can be disabled. Using the Checkpoint service is optional and can be disabled.
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2016-11-01 12:53:13 +00:00
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See [`disable_anonymous_signature`](/docs/agent/configuration/index.html#disable_anonymous_signature)
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and [`disable_update_check`](/docs/agent/configuration/index.html#disable_update_check).
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## Q: How does Atlas integration work?
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Nomad makes use of a HashiCorp service called [SCADA](http://scada.hashicorp.com)
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(Supervisory Control And Data Acquisition). The SCADA system allows clients to maintain
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long-running connections to Atlas. Atlas can in turn provide auto-join facilities for
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Nomad agents (supervisory control) and a dashboard showing the state of the system (data acquisition).
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Using the SCADA service is optional. SCADA is only enabled by opt-in.
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## Q: Is Nomad eventually or strongly consistent?
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Nomad makes use of both a [consensus protocol](/docs/internals/consensus.html) and
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a [gossip protocol](/docs/internals/gossip.html). The consensus protocol is strongly
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consistent, and is used for all state replication and scheduling. The gossip protocol
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is used to manage the addresses of servers for automatic clustering and multi-region
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2016-04-21 20:15:01 +00:00
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federation. This means all data that is managed by Nomad is strongly consistent.
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