istio.io/archive/v1.1/help/ops/traffic-management/locality-load-balancing/index.html

54 lines
23 KiB
HTML

<!doctype html><html lang=en itemscope itemtype=https://schema.org/WebPage><head><meta charset=utf-8><meta http-equiv=x-ua-compatible content="IE=edge"><meta name=viewport content="width=device-width,initial-scale=1,shrink-to-fit=no"><meta name=theme-color content=#466BB0><meta name=title content="Locality Load Balancing"><meta name=description content="Information on how to enable and understand Locality Load Balancing."><meta name=keywords content="microservices,services,mesh,locality,load balancing,priority,prioritized"><meta property=og:title content="Locality Load Balancing"><meta property=og:type content=website><meta property=og:description content="Information on how to enable and understand Locality Load Balancing."><meta property=og:url content=/v1.1/help/ops/traffic-management/locality-load-balancing/><meta property=og:image content=/v1.1/img/istio-whitelogo-bluebackground-framed.svg><meta property=og:image:alt content="Istio Logo"><meta property=og:image:width content=112><meta property=og:image:height content=150><meta property=og:site_name content=Istio><meta name=twitter:card content=summary><meta name=twitter:site content=@IstioMesh><title>Istioldie 1.1 / Locality Load Balancing</title><script async src="https://www.googletagmanager.com/gtag/js?id=UA-98480406-2"></script><script>window.dataLayer=window.dataLayer||[];function gtag(){dataLayer.push(arguments);}
gtag('js',new Date());gtag('config','UA-98480406-2');</script><link rel=alternate type=application/rss+xml title="Istio Blog" href=/v1.1/feed.xml><link rel="shortcut icon" href=/v1.1/favicons/favicon.ico><link rel=apple-touch-icon href=/v1.1/favicons/apple-touch-icon-180x180.png sizes=180x180><link rel=icon type=image/png href=/v1.1/favicons/favicon-16x16.png sizes=16x16><link rel=icon type=image/png href=/v1.1/favicons/favicon-32x32.png sizes=32x32><link rel=icon type=image/png href=/v1.1/favicons/android-36x36.png sizes=36x36><link rel=icon type=image/png href=/v1.1/favicons/android-48x48.png sizes=48x48><link rel=icon type=image/png href=/v1.1/favicons/android-72x72.png sizes=72x72><link rel=icon type=image/png href=/v1.1/favicons/android-96x96.png sizes=96xW96><link rel=icon type=image/png href=/v1.1/favicons/android-144x144.png sizes=144x144><link rel=icon type=image/png href=/v1.1/favicons/android-192x192.png sizes=192x192><link rel=manifest href=/v1.1/manifest.json><meta name=apple-mobile-web-app-title content=Istio><meta name=application-name content=Istio><link rel=stylesheet href="https://fonts.googleapis.com/css?family=Work+Sans:400|Chivo:400|Work+Sans:500,300,600,300italic,400italic,500italic,600italic|Chivo:500,300,600,300italic,400italic,500italic,600italic"><link rel=stylesheet href=/v1.1/css/all.css></head><body class="language-unknown archive-site"><script src=/v1.1/js/themes_init.min.js></script><script>const branchName="release-1.1";const docTitle="Locality Load Balancing";const iconFile="\/v1.1/img/icons.svg";const buttonCopy='Copy to clipboard';const buttonPrint='Print';const buttonDownload='Download';</script><script src="https://www.google.com/cse/brand?form=search-form" defer></script><script src=/v1.1/js/all.min.js data-manual defer></script><header><nav><a id=brand href=/v1.1/><span class=logo><svg viewBox="0 0 300 300"><circle cx="150" cy="150" r="146" stroke-width="2" /><path d="M65 240H225L125 270z"/><path d="M65 230l60-10V110z"/><path d="M135 220l90 10L135 30z"/></svg></span><span class=name>Istioldie 1.1</span></a><div id=hamburger><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#hamburger"/></svg></div><div id=header-links><a title="Learn how to deploy, use, and operate Istio." href=/v1.1/docs/>Docs</a>
<a title="Posts about using Istio." href=/v1.1/blog/2019/announcing-1.1.9/>Blog</a>
<span title="A bunch of resources to help you deploy, configure and use Istio.">Help</span>
<a title="Get a bit more in-depth info about the Istio project." href=/v1.1/about/>About</a><div class=menu><button id=gearDropdownButton class=menu-trigger title="Options and settings" aria-label="Options and Settings" aria-controls=gearDropdownContent><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#gear"/></svg></button><div id=gearDropdownContent class=menu-content aria-labelledby=gearDropdownButton role=menu><a tabindex=-1 role=menuitem lang=en id=switch-lang-en class=active>English</a>
<a tabindex=-1 role=menuitem lang=zh id=switch-lang-zh>中文</a><div role=separator></div><a tabindex=-1 role=menuitem class=active id=light-theme-item>Light Theme</a>
<a tabindex=-1 role=menuitem id=dark-theme-item>Dark Theme</a><div role=separator></div><a tabindex=-1 role=menuitem id=syntax-coloring-item>Color Examples</a><div role=separator></div><h6>Other versions of this site</h6><a tabindex=-1 role=menuitem onclick="navigateToUrlOrRoot('https://istio.io/help\/ops\/traffic-management\/locality-load-balancing\/');return false;">Current Release</a>
<a tabindex=-1 role=menuitem onclick="navigateToUrlOrRoot('https://preliminary.istio.io/help\/ops\/traffic-management\/locality-load-balancing\/');return false;">Next Release</a>
<a tabindex=-1 role=menuitem href=https://archive.istio.io>Older Releases</a></div></div><button id=search-show title="Search this site" aria-label=Search><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#magnifier"/></svg></button></div><form id=search-form name=cse role=search><input type=hidden name=cx value=013699703217164175118:iwwf17ikgf4>
<input type=hidden name=ie value=utf-8>
<input type=hidden name=hl value=en>
<input type=hidden id=search-page-url value=/v1.1/search.html>
<input id=search-textbox class=form-control name=q type=search aria-label="Search this site">
<button id=search-close title="Cancel search" type=reset aria-label="Cancel search"><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#cancel-x"/></svg></button></form></nav></header><main class=primary><div id=sidebar-container class="sidebar-container sidebar-offcanvas"><nav id=sidebar aria-label="Section Navigation"><div class=directory><div class=card><div id=header0 class=header title="A bunch of resources to help you deploy, configure and use Istio."><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#help"/></svg>Need Help?</div><div class="body default" aria-labelledby=header0><ul role=tree aria-expanded=true aria-labelledby=header0><li role=treeitem aria-label="Operations Guide"><button class=show aria-hidden=true></button><a title="Hints, tips, tricks about running an Istio mesh." href=/v1.1/help/ops/>Operations Guide</a><ul role=group aria-expanded=true><li role=none><a role=treeitem title="Describes how to use component-level logging to get insights into a running component's behavior." href=/v1.1/help/ops/component-logging/>Component Logging</a></li><li role=none><a role=treeitem title="Describes how to use ControlZ to get insight into individual running components." href=/v1.1/help/ops/controlz/>Component Introspection</a></li><li role=none><a role=treeitem title="How to do low-level debugging of Istio components." href=/v1.1/help/ops/component-debugging/>Component Debugging</a></li><li role=treeitem aria-label="Traffic Management"><button class=show aria-hidden=true></button><a title="Helps you manage the networking aspects of a running mesh." href=/v1.1/help/ops/traffic-management/>Traffic Management</a><ul role=group aria-expanded=true class=leaf-section><li role=none><a role=treeitem title="An introduction to Istio networking operational aspects." href=/v1.1/help/ops/traffic-management/introduction/>Introduction to Network Operations</a></li><li role=none><a role=treeitem title="Provides specific deployment and configuration guidelines." href=/v1.1/help/ops/traffic-management/deploy-guidelines/>Deployment and Configuration Guidelines</a></li><li role=none><a role=treeitem title="Describes common networking issues and how to recognize and avoid them." href=/v1.1/help/ops/traffic-management/troubleshooting/>Troubleshooting Networking Issues</a></li><li role=none><a role=treeitem title="Describes tools and techniques to diagnose Envoy configuration issues related to traffic management." href=/v1.1/help/ops/traffic-management/proxy-cmd/>Debugging Envoy and Pilot</a></li><li role=none><span role=treeitem class=current title="Information on how to enable and understand Locality Load Balancing.">Locality Load Balancing</span></li></ul></li><li role=treeitem aria-label=Security><button aria-hidden=true></button><a title="Helps you manage the security aspects of a running mesh." href=/v1.1/help/ops/security/>Security</a><ul role=group aria-expanded=false class=leaf-section><li role=none><a role=treeitem title="Demonstrates how to debug authorization." href=/v1.1/help/ops/security/debugging-authorization/>Debugging Authorization</a></li><li role=none><a role=treeitem title="What to do if Citadel is not behaving properly." href=/v1.1/help/ops/security/repairing-citadel/>Repairing Citadel</a></li><li role=none><a role=treeitem title="What to do if you suspect problems with Istio keys and certificates." href=/v1.1/help/ops/security/keys-and-certs/>Keys and Certificates</a></li><li role=none><a role=treeitem title="What to do if mutual TLS authentication isn't working." href=/v1.1/help/ops/security/mutual-tls/>Mutual TLS</a></li><li role=none><a role=treeitem title="Authorization is enabled, but requests make it through anyway." href=/v1.1/help/ops/security/authorization-permissive/>Authorization Too Permissive</a></li><li role=none><a role=treeitem title="Authorization is enabled and no requests make it through to the service." href=/v1.1/help/ops/security/authorization-restrictive/>Authorization Too Restrictive</a></li><li role=none><a role=treeitem title="What to do if end-user authentication doesn't work." href=/v1.1/help/ops/security/end-user-auth/>End User Authentication</a></li><li role=none><a role=treeitem title="Learn how to extend the lifetime of the Istio self-signed root certificate." href=/v1.1/help/ops/security/root-transition/>Extending Self-Signed Certificate Lifetime</a></li></ul></li><li role=treeitem aria-label=Telemetry><button aria-hidden=true></button><a title="Helps you manage telemetry collection and visualization in a running mesh." href=/v1.1/help/ops/telemetry/>Telemetry</a><ul role=group aria-expanded=false class=leaf-section><li role=none><a role=treeitem title="Diagnose problems where metrics are not being collected." href=/v1.1/help/ops/telemetry/missing-metrics/>Missing Metrics</a></li><li role=none><a role=treeitem title="Dealing with Grafana issues." href=/v1.1/help/ops/telemetry/grafana/>Grafana</a></li><li role=none><a role=treeitem title="Fine-grained control of Envoy statistics." href=/v1.1/help/ops/telemetry/envoy-stats/>Envoy Statistics</a></li></ul></li><li role=treeitem aria-label="Installation and Setup"><button aria-hidden=true></button><a title="Helps you diagnose and repair Istio installations." href=/v1.1/help/ops/setup/>Installation and Setup</a><ul role=group aria-expanded=false class=leaf-section><li role=none><a role=treeitem title="Provides a general overview of Istio's use of Kubernetes webhooks and the related issues that can arise." href=/v1.1/help/ops/setup/webhook/>Dynamic Admission Webhooks Overview</a></li><li role=none><a role=treeitem title="Describes Istio's use of Kubernetes webhooks for server-side configuration validation." href=/v1.1/help/ops/setup/validation/>Configuration Validation Webhook</a></li><li role=none><a role=treeitem title="Describes Istio's use of Kubernetes webhooks for automatic sidecar injection." href=/v1.1/help/ops/setup/injection/>Sidecar Injection Webhook</a></li><li role=none><a role=treeitem title="Describes how to check which capabilities are allowed for your pods." href=/v1.1/help/ops/setup/required-pod-capabilities/>Required Pod Capabilities</a></li><li role=none><a role=treeitem title="Shows how to do health checking for Istio services." href=/v1.1/help/ops/setup/app-health-check/>Health Checking of Istio Services</a></li></ul></li><li role=none><a role=treeitem title="Advice on tackling common problems with Istio." href=/v1.1/help/ops/misc/>Miscellaneous</a></li></ul></li><li role=treeitem aria-label=FAQ><button aria-hidden=true></button><a title="Frequently Asked Questions about Istio." href=/v1.1/help/faq/>FAQ</a><ul role=group aria-expanded=false class=leaf-section><li role=none><a role=treeitem title="General Q &amp; A." href=/v1.1/help/faq/general/>General</a></li><li role=none><a role=treeitem title="Setup Q &amp; A." href=/v1.1/help/faq/setup/>Setup</a></li><li role=none><a role=treeitem title="Security Q &amp; A." href=/v1.1/help/faq/security/>Security</a></li><li role=none><a role=treeitem title="Mixer Q &amp; A." href=/v1.1/help/faq/mixer/>Mixer</a></li><li role=none><a role=treeitem title="Metrics and Logs Q &amp; A." href=/v1.1/help/faq/metrics-and-logs/>Metrics and Logs</a></li><li role=none><a role=treeitem title="Distributed Tracing Q &amp; A." href=/v1.1/help/faq/distributed-tracing/>Distributed Tracing</a></li><li role=none><a role=treeitem title="Traffic Management Q &amp; A." href=/v1.1/help/faq/traffic-management/>Traffic Management</a></li></ul></li><li role=none><a role=treeitem title="A glossary of common Istio terms." href=/v1.1/help/glossary/>Glossary</a></li></ul></div></div></div></nav></div><div class=article-container><button tabindex=-1 id=sidebar-toggler title="Toggle the navigation bar"><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#pull"/></svg></button><nav aria-label=Breadcrumb><ol><li><a href=/v1.1/ title="Connect, secure, control, and observe services.">Istio</a></li><li><a href=/v1.1/help/ title="A bunch of resources to help you deploy, configure and use Istio.">Help</a></li><li><a href=/v1.1/help/ops/ title="Hints, tips, tricks about running an Istio mesh.">Operations Guide</a></li><li><a href=/v1.1/help/ops/traffic-management/ title="Helps you manage the networking aspects of a running mesh.">Traffic Management</a></li><li>Locality Load Balancing</li></ol></nav><article aria-labelledby=title><div class=title-area><div><h1 id=title>Locality Load Balancing</h1><p class=byline><span title="460 words"><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#clock"/></svg><span>&nbsp;</span>3 minute read</span></p></div></div><nav class=toc-inlined aria-label="Table of Contents"><div><hr><ol><li role=none aria-label="Enabling Locality Load Balancing"><a href=#enabling-locality-load-balancing>Enabling Locality Load Balancing</a><li role=none aria-label=Requirements><a href=#requirements>Requirements</a><li role=none aria-label="Locality-prioritized load balancing"><a href=#locality-prioritized-load-balancing>Locality-prioritized load balancing</a><ol><li role=none aria-label="Overriding the Locality Fail-over"><a href=#overriding-the-locality-fail-over>Overriding the Locality Fail-over</a></ol></li><li role=none aria-label="Locality-weighted load balancing"><a href=#locality-weighted-load-balancing>Locality-weighted load balancing</a></ol><hr></div></nav><p>A locality defines a geographic location within your mesh using the following triplet:</p><ul><li>Region</li><li>Zone</li><li>Sub-zone</li></ul><p>The geographic location typically represents a data center. Istio uses
this information to prioritize load balancing pools to control
the geographic location where requests are sent.</p><h2 id=enabling-locality-load-balancing>Enabling Locality Load Balancing</h2><p>This feature is experimental and off by default in 1.1. To enable locality load balancing,
set the <code>PILOT_ENABLE_LOCALITY_LOAD_BALANCING</code> environment variable in all Pilot instances.</p><h2 id=requirements>Requirements</h2><p>Currently, the service discovery platform populates the locality automatically.
In Kubernetes, a pod&rsquo;s locality is determined via the <a href=https://kubernetes.io/docs/reference/kubernetes-api/labels-annotations-taints/#failure-domain-beta-kubernetes-io-region>well-known labels for region and zone</a>
on the node it is deployed. If you are using a hosted Kubernetes service your cloud provider
should configure this for you. If you are running your own Kubernetes cluster you will need
to add these labels to your nodes. The sub-zone concept doesn&rsquo;t exist in Kubernetes.
As a result, this field does not need to be configured.</p><p>In order for Istio to determine locality, a Service must be associated with the caller.</p><h2 id=locality-prioritized-load-balancing>Locality-prioritized load balancing</h2><p><em>Locality-prioritized load balancing</em> is the default behavior for <em>locality load balancing</em>.
In this mode, Istio tells Envoy to prioritize traffic to the workload instances most closely matching
the locality of the Envoy sending the request. When all instances are healthy, the requests
remains within the same locality. When instances become unhealthy, traffic spills over to
instances in the next prioritized locality. This behavior continues until all localities are
receiving traffic. You can find the exact percentages in the <a href=https://www.envoyproxy.io/docs/envoy/latest/intro/arch_overview/upstream/load_balancing/priority#priority-levels>Envoy documentation</a>.</p><p>A typical prioritization for an Envoy with a locality of <code>us-west/zone2</code> is as follows:</p><ul><li>Priority 0: <code>us-west/zone2</code></li><li>Priority 1: <code>us-west/zone1</code>, <code>us-west/zone3</code></li><li>Priority 2: <code>us-east/zone1</code>, <code>us-east/zone2</code>, <code>eu-west/zone1</code></li></ul><p>The hierarchy of prioritization matches in the following order:</p><ol><li>Region</li><li>Zone</li><li>Sub-zone</li></ol><p>Proxies in the same zone but different regions are not considered local to one another.</p><p>In order for Envoy to determine when instances are unhealthy, an <a href=/v1.1/docs/reference/config/networking/v1alpha3/destination-rule/#OutlierDetection>Outlier Detection</a>
rule must be defined for each service.</p><h3 id=overriding-the-locality-fail-over>Overriding the Locality Fail-over</h3><p>Sometimes, you need to constrain the traffic fail-over to avoid sending traffic to
endpoints across the globe when there are not enough healthy endpoints in the
same region. This behavior is useful when sending fail-over traffic across regions
would not improve service health or many other reasons including regulatory controls.
To constrain traffic to a region, configure the <code>localityLbSetting</code> option using Helm. See the
<a href=/v1.1/docs/reference/config/istio.mesh.v1alpha1/#LocalityLoadBalancerSetting>Locality load balancing reference guide</a>
for options.</p><p>An example configuration:</p><pre><code class=language-yaml data-expandlinks=true>global:
localityLbSetting:
failover:
- from: us-east
to: eu-west
- from: us-west
to: us-east
</code></pre><h2 id=locality-weighted-load-balancing>Locality-weighted load balancing</h2><p>Locality-weighted load balancing distributes user-defined percentages of traffic to certain localities.</p><p>For example, if we want to keep 80% of traffic within our region, and send 20% of traffic out of region:</p><pre><code class=language-yaml data-expandlinks=true>global:
localityLbSetting:
- from: &#34;us-central1/*&#34;
to:
&#34;us-central1/*&#34;: 80
&#34;us-central2/*&#34;: 20
</code></pre></article><nav class=pagenav><div class=left><a title="Describes tools and techniques to diagnose Envoy configuration issues related to traffic management." href=/v1.1/help/ops/traffic-management/proxy-cmd/><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#left-arrow"/></svg>Debugging Envoy and Pilot</a></div><div class=right></div></nav><div id=endnotes-container aria-hidden=true><h2>Links</h2><ol id=endnotes></ol></div></div><div class=toc-container><nav class=toc aria-label="Table of Contents"><div id=toc><ol><li role=none aria-label="Enabling Locality Load Balancing"><a href=#enabling-locality-load-balancing>Enabling Locality Load Balancing</a><li role=none aria-label=Requirements><a href=#requirements>Requirements</a><li role=none aria-label="Locality-prioritized load balancing"><a href=#locality-prioritized-load-balancing>Locality-prioritized load balancing</a><ol><li role=none aria-label="Overriding the Locality Fail-over"><a href=#overriding-the-locality-fail-over>Overriding the Locality Fail-over</a></ol></li><li role=none aria-label="Locality-weighted load balancing"><a href=#locality-weighted-load-balancing>Locality-weighted load balancing</a></ol></div></nav></div></main><footer><div class=user-links><a class=channel title="Go download Istio 1.1.9 now" href=https://github.com/istio/istio/releases/tag/1.1.9 aria-label="Download Istio"><span>download</span><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#download"/></svg>
</a><a class=channel title="Join the Istio discussion board to participate in discussions and get help troubleshooting problems" href=https://discuss.istio.io aria-label="Istio discussion board"><span>discuss</span><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#discourse"/></svg></a>
<a class=channel title="Stack Overflow is where you can ask questions and find curated answers on deploying, configuring, and using Istio" href=https://stackoverflow.com/questions/tagged/istio aria-label="Stack Overflow"><span>stack overflow</span><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#stackoverflow"/></svg></a>
<a class=channel title="Follow us on Twitter to get the latest news" href=https://twitter.com/IstioMesh aria-label=Twitter><span>twitter</span><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#twitter"/></svg></a><div class=tag>for everyone</div></div><div class=info><p class=copyright>Istio Archive
1.1.9<br>&copy; 2019 Istio Authors, <a href=https://policies.google.com/privacy>Privacy Policy</a><br>Archived on June 18, 2019</p></div><div class=dev-links><a class=channel title="GitHub is where development takes place on Istio code" href=https://github.com/istio/community aria-label=GitHub><span>github</span><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#github"/></svg></a>
<a class=channel title="Interactively discuss issues with the Istio community on Slack" href=https://istio.slack.com aria-label=slack><span>slack</span><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#slack"/></svg></a>
<a class=channel title="Access our team drive if you'd like to take a look at the Istio technical design documents" href=https://groups.google.com/forum/#!forum/istio-team-drive-access aria-label="team drive"><span>drive</span><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#drive"/></svg></a>
<a class=channel title="If you'd like to contribute to the Istio project, consider participating in our working groups" href=https://github.com/istio/community/blob/master/WORKING-GROUPS.md aria-label="working groups"><span>working groups</span><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#working-groups"/></svg></a><div class=tag>for developers</div></div></footer><div id=scroll-to-top-container aria-hidden=true><button id=scroll-to-top title="Back to top"><svg class="icon"><use xlink:href="/v1.1/img/icons.svg#top"/></svg></button></div></body></html>