Google Git
Sign in
apache / james-site / a15da97d6f43d2450183d8ff4b8722aa4ad8b24d / . / james-distributed-app / 3.8.0 / architecture / specialized-instances.html
blob: ea2be771eb57e152d305566cc922b7c32ee77478 [file] [log] [blame]
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width,initial-scale=1">
<title>Distributed James Server &mdash; Specialized instances :: Apache James</title>
<meta name="generator" content="Antora 3.1.2">
<link rel="stylesheet" href="../../../_/css/site.css">
</head>
<body class="article">
<header class="header">
<nav class="navbar">
<div class="navbar-brand">
<a class="navbar-item" href="https://james.apache.org"><img src="/_/img/james.svg" alt="james logo"> Apache James</a>
<button class="navbar-burger" data-target="topbar-nav">
<span></span>
<span></span>
<span></span>
</button>
</div>
<div id="topbar-nav" class="navbar-menu">
<div class="navbar-end">
<a class="navbar-item" href="#">Home</a>
<div class="navbar-item has-dropdown is-hoverable">
<a class="navbar-link" href="#">Products</a>
<div class="navbar-dropdown">
<div class="navbar-item"><strong>James server</strong></div>
<a class="navbar-item" href="https://github.com/apache/james-project">Repository</a>
<a class="navbar-item" href="https://issues.apache.org/jira/projects/JAMES/issues">Issue Tracker</a>
<hr class="navbar-divider">
<a class="navbar-item" href="https://james.apache.org/mime4j/index.html">Mime4J</a>
<a class="navbar-item" href="https://james.apache.org/jsieve/index.html">jSieve</a>
<a class="navbar-item" href="https://james.apache.org/jspf/index.html">jSPF</a>
<a class="navbar-item" href="https://james.apache.org/jdkim/index.html">jDKIM</a>
<a class="navbar-item" href="https://james.apache.org/hupa/index.html">HUPA</a>
</div>
</div>
<div class="navbar-item has-dropdown is-hoverable">
<a class="navbar-link" href="#">Community</a>
<div class="navbar-dropdown">
<!-- Not ideal but dropping the version in the href requires tweaking james-projet docs module first -->
<a class="navbar-item" href="/james-project/3.6.0/community/mailing-lists.html">Mailing lists</a>
<a class="navbar-item" href="https://gitter.im/apache/james-project"><svg version="1.1" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink" viewBox="0 0 32 32" class="logo-gitter-sign" data-v-44ebcb1a=""><rect x="15" y="5" width="2" height="10"></rect> <rect x="10" y="5" width="2" height="20"></rect> <rect x="5" y="5" width="2" height="20"></rect> <rect width="2" height="15"></rect></svg> Gitter</a>
<a class="navbar-item" href="https://twitter.com/ApacheJames">
<span class="icon">
<svg aria-hidden="true" data-icon="twitter" role="img" xmlns="http://www.w3.org/2000/svg" viewBox="0 0 512 512">
<path fill="#57aaee" d="M459.37 151.716c.325 4.548.325 9.097.325 13.645 0 138.72-105.583 298.558-298.558 298.558-59.452 0-114.68-17.219-161.137-47.106 8.447.974 16.568 1.299 25.34 1.299 49.055 0 94.213-16.568 130.274-44.832-46.132-.975-84.792-31.188-98.112-72.772 6.498.974 12.995 1.624 19.818 1.624 9.421 0 18.843-1.3 27.614-3.573-48.081-9.747-84.143-51.98-84.143-102.985v-1.299c13.969 7.797 30.214 12.67 47.431 13.319-28.264-18.843-46.781-51.005-46.781-87.391 0-19.492 5.197-37.36 14.294-52.954 51.655 63.675 129.3 105.258 216.365 109.807-1.624-7.797-2.599-15.918-2.599-24.04 0-57.828 46.782-104.934 104.934-104.934 30.213 0 57.502 12.67 76.67 33.137 23.715-4.548 46.456-13.32 66.599-25.34-7.798 24.366-24.366 44.833-46.132 57.827 21.117-2.273 41.584-8.122 60.426-16.243-14.292 20.791-32.161 39.308-52.628 54.253z"></path>
</svg>
</span> Twitter
</a>
<a class="navbar-item" href="#"> <svg class="octicon octicon-mark-github v-align-middle" viewBox="0 0 16 16" version="1.1" aria-hidden="true"><path fill-rule="evenodd" d="M8 0C3.58 0 0 3.58 0 8c0 3.54 2.29 6.53 5.47 7.59.4.07.55-.17.55-.38 0-.19-.01-.82-.01-1.49-2.01.37-2.53-.49-2.69-.94-.09-.23-.48-.94-.82-1.13-.28-.15-.68-.52-.01-.53.63-.01 1.08.58 1.23.82.72 1.21 1.87.87 2.33.66.07-.52.28-.87.51-1.07-1.78-.2-3.64-.89-3.64-3.95 0-.87.31-1.59.82-2.15-.08-.2-.36-1.02.08-2.12 0 0 .67-.21 2.2.82.64-.18 1.32-.27 2-.27.68 0 1.36.09 2 .27 1.53-1.04 2.2-.82 2.2-.82.44 1.1.16 1.92.08 2.12.51.56.82 1.27.82 2.15 0 3.07-1.87 3.75-3.65 3.95.29.25.54.73.54 1.48 0 1.07-.01 1.93-.01 2.2 0 .21.15.46.55.38A8.013 8.013 0 0016 8c0-4.42-3.58-8-8-8z"></path></svg> Github</a>
</div>
</div>
<!-- <div class="navbar-item">
<span class="control">
<a class="button is-primary" href="#">Download</a>
</span>
</div> -->
</div>
</div>
</nav>
</header>
<div class="body">
<div class="nav-container" data-component="james-distributed-app" data-version="3.8.0">
<aside class="nav">
<div class="panels">
<div class="nav-panel-menu is-active" data-panel="menu">
<nav class="nav-menu">
<button class="nav-menu-toggle" aria-label="Toggle expand/collapse all" style="display: none"></button>
<h3 class="title"><a href="../index.html">Apache James Distributed Server</a></h3>
<ul class="nav-list">
<li class="nav-item" data-depth="0">
<ul class="nav-list">
<li class="nav-item" data-depth="1">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../index.html">Distributed James Application</a>
<ul class="nav-list">
<li class="nav-item" data-depth="2">
<a class="nav-link" href="../objectives.html">Objectives and motivation</a>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="index.html">Architecture</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="implemented-standards.html">Implemented standards</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="consistency-model.html">Consistency Model</a>
</li>
<li class="nav-item is-current-page" data-depth="3">
<a class="nav-link" href="specialized-instances.html">Specialized instances</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../run/index.html">Run</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../run/run-java.html">Run with Java</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../run/run-docker.html">Run with Docker</a>
</li>
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../run/run-kubernetes.html">Run with Kubernetes</a>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../run/k8s-checklist.html">Deployment Checklist</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../run/k8s-logsMetrics.html">Logs &amp; Metrics</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../run/k8s-values.html">values.yaml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../run/k8s-secrets.html">secrets.yaml</a>
</li>
</ul>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../configure/index.html">Configuration</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<span class="nav-text">Protocols</span>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/imap.html">imapserver.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/jmap.html">jmap.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/jmx.html">jmx.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/smtp.html">smtpserver.xml &amp; lmtpserver.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/smtp-hooks.html">Packaged SMTP hooks</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/pop3.html">pop3server.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/webadmin.html">webadmin.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/ssl.html">SSL &amp; TLS</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/sieve.html">Sieve &amp; ManageSieve</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<span class="nav-text">Storage dependencies</span>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/blobstore.html">blobstore.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/cassandra.html">cassandra.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/opensearch.html">opensearch.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/rabbitmq.html">rabbitmq.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/redis.html">redis.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/tika.html">tika.properties</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<span class="nav-text">Core components</span>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/batchsizes.html">batchsizes.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/dns.html">dnsservice.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/domainlist.html">domainlist.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/healthcheck.html">healthcheck.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/mailetcontainer.html">mailetcontainer.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/mailets.html">Packaged Mailets</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/matchers.html">Packaged Matchers</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/mailrepositorystore.html">mailrepositorystore.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/recipientrewritetable.html">recipientrewritetable.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/search.html">search.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/usersrepository.html">usersrepository.xml</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="3">
<button class="nav-item-toggle"></button>
<span class="nav-text">Extensions</span>
<ul class="nav-list">
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/vault.html">deletedMessageVault.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/extensions.html">extensions.properties</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/listeners.html">listeners.xml</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/spam.html">Anti-Spam setup</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/remote-delivery-error-handling.html">About RemoteDelivery error handling</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/collecting-contacts.html">Contact collection</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/collecting-events.html">Event collection</a>
</li>
<li class="nav-item" data-depth="4">
<a class="nav-link" href="../configure/dsn.html">ESMTP DSN support</a>
</li>
</ul>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../operate/index.html">Operate</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/guide.html">Operator guide</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/performanceChecklist.html">Performance checklist</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/logging.html">Logging</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/webadmin.html">WebAdmin REST administration API</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/metrics.html">Metrics</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/migrating.html">Migrating existing data</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/cli.html">Command Line Interface</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/cassandra-migration.html">Cassandra migration</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../operate/security.html">Security checklist</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../extending/index.html">Extending server behavior</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../extending/mail-processing.html">Custom mail processing components</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../extending/mailbox-listeners.html">Custom Mailbox Listeners</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../extending/smtp-hooks.html">Custom SMTP hooks</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../extending/webadmin-routes.html">Custom WebAdmin routes</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../extending/imap.html">Custom IMAP processing</a>
</li>
</ul>
</li>
<li class="nav-item" data-depth="2">
<button class="nav-item-toggle"></button>
<a class="nav-link" href="../benchmark/index.html">Performance benchmark</a>
<ul class="nav-list">
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../benchmark/db-benchmark.html">Database benchmarks</a>
</li>
<li class="nav-item" data-depth="3">
<a class="nav-link" href="../benchmark/james-benchmark.html">James benchmarks</a>
</li>
</ul>
</li>
</ul>
</li>
</ul>
</li>
</ul>
</nav>
</div>
<div class="nav-panel-explore" data-panel="explore">
<div class="context">
<span class="title">Apache James Distributed Server</span>
<span class="version">3.8.0 SNAPSHOT</span>
</div>
<ul class="components">
<li class="component is-current">
<div class="title"><a href="../index.html">Apache James Distributed Server</a></div>
<ul class="versions">
<li class="version is-current is-latest">
<a href="../index.html">3.8.0 SNAPSHOT</a>
</li>
</ul>
</li>
<li class="component">
<div class="title"><a href="../../../james-project/3.8.0/index.html">Apache James Server</a></div>
<ul class="versions">
<li class="version is-latest">
<a href="../../../james-project/3.8.0/index.html">3.8.0 SNAPSHOT</a>
</li>
<li class="version">
<a href="../../../james-project/3.6.0/index.html">3.6.0 Snapshot</a>
</li>
</ul>
</li>
<li class="component">
<div class="title"><a href="../../../james-site/latest/index.html">Apache James Site</a></div>
<ul class="versions">
<li class="version is-latest">
<a href="../../../james-site/latest/index.html">latest</a>
</li>
</ul>
</li>
</ul>
</div>
</div>
</aside>
</div>
<main class="article">
<div class="toolbar" role="navigation">
<button class="nav-toggle"></button>
<a href="../../../james-site/latest/homepage.html" class="home-link"></a>
<nav class="breadcrumbs" aria-label="breadcrumbs">
<ul>
<li><a href="../index.html">Apache James Distributed Server</a></li>
<li><a href="../index.html">Distributed James Application</a></li>
<li><a href="index.html">Architecture</a></li>
<li><a href="specialized-instances.html">Specialized instances</a></li>
</ul>
</nav>
<div class="edit-this-page"><a href="https://github.com/apache/james-project/blob/master/server/apps/distributed-app/docs/modules/ROOT/pages/architecture/specialized-instances.adoc">Edit this Page</a></div>
</div>
<div class="content">
<aside class="toc sidebar" data-title="Contents" data-levels="2">
<div class="toc-menu"></div>
</aside>
<article class="doc">
<h1 class="page">Distributed James Server &mdash; Specialized instances</h1>
<div class="paragraph">
<p>While it is perfectly possible to deploy homogeneous James instances, with the same configuration and thus the same
protocols and the same responsibilities one might want to investigate in 'Specialized instances'.</p>
</div>
<div class="paragraph">
<p>This deployment topology consists of Distributed James servers with heterogeneous configurations on top of shared
data-bases. Groups of James servers will thus handle various protocols and have different responsibilities.</p>
</div>
<div class="paragraph">
<p>This approach limits cascading failures across protocols and services. Think of <strong>OutOfMemoryErrors</strong>, Cassandra driver
queue overuse, CPUs starvation, etc.</p>
</div>
<div class="paragraph">
<p>However, we can&#8217;t speak of micro-services here: all James instances runs the same code, James is still a monolith, and
databases need to be shared across instances.</p>
</div>
<div class="imageblock">
<div class="content">
<img src="../_images/specialized-instances.png" alt="Example of Specialized instances topology">
</div>
</div>
<div class="paragraph">
<p>We speak of:</p>
</div>
<div class="ulist">
<ul>
<li>
<p><strong>Front-line servers</strong> serves protocols. James enables to easily turn protocols on and off. Typically, each protocol would
be isolated in its own group of James instances: james-imap, james-jmap, james-smtp, james-webadmin, etc&#8230;&#8203; Refer to
protocols configuration files to learn more.</p>
</li>
<li>
<p><strong>Back-office servers</strong> handles other services like:</p>
</li>
<li>
<p>Mail processing.</p>
</li>
<li>
<p>Remote delivery.</p>
</li>
<li>
<p>Event processing.</p>
</li>
<li>
<p>Task execution.</p>
</li>
</ul>
</div>
<div class="paragraph">
<p>Front-line servers will likely not handle back office responsibilities (but be sure to have back-office servers that do!).</p>
</div>
<div class="ulist">
<ul>
<li>
<p><a href="../configure/mailetcontainer.html" class="xref page">Mail processing can be switched off</a>.</p>
</li>
<li>
<p><a href="../configure/listeners.html" class="xref page">Mailbox event processing can be switched off</a>.</p>
</li>
<li>
<p><a href="../configure/rabbitmq.html" class="xref page">Task execution can be switched off</a>.</p>
</li>
<li>
<p>Remote Delivery service is not started if the RemoteDelivery mailet is not positioned in mailetcontainer.xml.</p>
</li>
</ul>
</div>
<div class="paragraph">
<p>Of course, the above instances can be collocated at will, to reach some intermediate deployments with fewer
instances to mitigate costs.</p>
</div>
</article>
</div>
</main>
</div>
<footer class="footer">
<p>This page was built using the Antora default UI.</p>
<p>The source code for this UI is licensed under the terms of the MPL-2.0 license.</p>
</footer>
<script id="site-script" src="../../../_/js/site.js" data-ui-root-path="../../../_"></script>
<script async src="../../../_/js/vendor/highlight.js"></script>
</body>
</html>