1 line
No EOL
30 KiB
HTML
1 line
No EOL
30 KiB
HTML
<!doctype html><html lang=en class=no-js> <head><meta charset=utf-8><meta name=viewport content="width=device-width,initial-scale=1"><link href=https://kubernetes.github.io/ingress-nginx/enhancements/20190815-zone-aware-routing/ rel=canonical><link rel=icon href=../../assets/images/favicon.png><meta name=generator content="mkdocs-1.5.3, mkdocs-material-9.4.5"><title>Availability zone aware routing - Ingress-Nginx Controller</title><link rel=stylesheet href=../../assets/stylesheets/main.6a10b989.min.css><link rel=stylesheet href=../../assets/stylesheets/palette.356b1318.min.css><link rel=preconnect href=https://fonts.gstatic.com crossorigin><link rel=stylesheet href="https://fonts.googleapis.com/css?family=Roboto:300,300i,400,400i,700,700i%7CRoboto+Mono:400,400i,700,700i&display=fallback"><style>:root{--md-text-font:"Roboto";--md-code-font:"Roboto Mono"}</style><link rel=stylesheet href=../../extra.css><script>__md_scope=new URL("../..",location),__md_hash=e=>[...e].reduce((e,_)=>(e<<5)-e+_.charCodeAt(0),0),__md_get=(e,_=localStorage,t=__md_scope)=>JSON.parse(_.getItem(t.pathname+"."+e)),__md_set=(e,_,t=localStorage,a=__md_scope)=>{try{t.setItem(a.pathname+"."+e,JSON.stringify(_))}catch(e){}}</script></head> <body dir=ltr data-md-color-scheme=default data-md-color-primary=teal data-md-color-accent=green> <input class=md-toggle data-md-toggle=drawer type=checkbox id=__drawer autocomplete=off> <input class=md-toggle data-md-toggle=search type=checkbox id=__search autocomplete=off> <label class=md-overlay for=__drawer></label> <div data-md-component=skip> <a href=#availability-zone-aware-routing class=md-skip> Skip to content </a> </div> <div data-md-component=announce> </div> <header class="md-header md-header--shadow md-header--lifted" data-md-component=header> <nav class="md-header__inner md-grid" aria-label=Header> <a href=../.. title="Ingress-Nginx Controller" class="md-header__button md-logo" aria-label="Ingress-Nginx Controller" data-md-component=logo> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M12 8a3 3 0 0 0 3-3 3 3 0 0 0-3-3 3 3 0 0 0-3 3 3 3 0 0 0 3 3m0 3.54C9.64 9.35 6.5 8 3 8v11c3.5 0 6.64 1.35 9 3.54 2.36-2.19 5.5-3.54 9-3.54V8c-3.5 0-6.64 1.35-9 3.54Z"/></svg> </a> <label class="md-header__button md-icon" for=__drawer> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M3 6h18v2H3V6m0 5h18v2H3v-2m0 5h18v2H3v-2Z"/></svg> </label> <div class=md-header__title data-md-component=header-title> <div class=md-header__ellipsis> <div class=md-header__topic> <span class=md-ellipsis> Ingress-Nginx Controller </span> </div> <div class=md-header__topic data-md-component=header-topic> <span class=md-ellipsis> Availability zone aware routing </span> </div> </div> </div> <label class="md-header__button md-icon" for=__search> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M9.5 3A6.5 6.5 0 0 1 16 9.5c0 1.61-.59 3.09-1.56 4.23l.27.27h.79l5 5-1.5 1.5-5-5v-.79l-.27-.27A6.516 6.516 0 0 1 9.5 16 6.5 6.5 0 0 1 3 9.5 6.5 6.5 0 0 1 9.5 3m0 2C7 5 5 7 5 9.5S7 14 9.5 14 14 12 14 9.5 12 5 9.5 5Z"/></svg> </label> <div class=md-search data-md-component=search role=dialog> <label class=md-search__overlay for=__search></label> <div class=md-search__inner role=search> <form class=md-search__form name=search> <input type=text class=md-search__input name=query aria-label=Search placeholder=Search autocapitalize=off autocorrect=off autocomplete=off spellcheck=false data-md-component=search-query required> <label class="md-search__icon md-icon" for=__search> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M9.5 3A6.5 6.5 0 0 1 16 9.5c0 1.61-.59 3.09-1.56 4.23l.27.27h.79l5 5-1.5 1.5-5-5v-.79l-.27-.27A6.516 6.516 0 0 1 9.5 16 6.5 6.5 0 0 1 3 9.5 6.5 6.5 0 0 1 9.5 3m0 2C7 5 5 7 5 9.5S7 14 9.5 14 14 12 14 9.5 12 5 9.5 5Z"/></svg> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M20 11v2H8l5.5 5.5-1.42 1.42L4.16 12l7.92-7.92L13.5 5.5 8 11h12Z"/></svg> </label> <nav class=md-search__options aria-label=Search> <button type=reset class="md-search__icon md-icon" title=Clear aria-label=Clear tabindex=-1> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M19 6.41 17.59 5 12 10.59 6.41 5 5 6.41 10.59 12 5 17.59 6.41 19 12 13.41 17.59 19 19 17.59 13.41 12 19 6.41Z"/></svg> </button> </nav> </form> <div class=md-search__output> <div class=md-search__scrollwrap data-md-scrollfix> <div class=md-search-result data-md-component=search-result> <div class=md-search-result__meta> Initializing search </div> <ol class=md-search-result__list role=presentation></ol> </div> </div> </div> </div> </div> <div class=md-header__source> <a href=https://github.com/kubernetes/ingress-nginx title="Go to repository" class=md-source data-md-component=source> <div class="md-source__icon md-icon"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 448 512"><!-- Font Awesome Free 6.4.2 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2023 Fonticons, Inc.--><path d="M439.55 236.05 244 40.45a28.87 28.87 0 0 0-40.81 0l-40.66 40.63 51.52 51.52c27.06-9.14 52.68 16.77 43.39 43.68l49.66 49.66c34.23-11.8 61.18 31 35.47 56.69-26.49 26.49-70.21-2.87-56-37.34L240.22 199v121.85c25.3 12.54 22.26 41.85 9.08 55a34.34 34.34 0 0 1-48.55 0c-17.57-17.6-11.07-46.91 11.25-56v-123c-20.8-8.51-24.6-30.74-18.64-45L142.57 101 8.45 235.14a28.86 28.86 0 0 0 0 40.81l195.61 195.6a28.86 28.86 0 0 0 40.8 0l194.69-194.69a28.86 28.86 0 0 0 0-40.81z"/></svg> </div> <div class=md-source__repository> kubernetes/ingress-nginx </div> </a> </div> </nav> <nav class=md-tabs aria-label=Tabs data-md-component=tabs> <div class=md-grid> <ul class=md-tabs__list> <li class=md-tabs__item> <a href=../.. class=md-tabs__link> Welcome </a> </li> <li class=md-tabs__item> <a href=../../deploy/ class=md-tabs__link> Deployment </a> </li> <li class=md-tabs__item> <a href=../../user-guide/nginx-configuration/ class=md-tabs__link> User Guide </a> </li> <li class=md-tabs__item> <a href=../../examples/ class=md-tabs__link> Examples </a> </li> <li class=md-tabs__item> <a href=../../developer-guide/getting-started/ class=md-tabs__link> Developer Guide </a> </li> <li class=md-tabs__item> <a href=../../faq/ class=md-tabs__link> FAQ </a> </li> </ul> </div> </nav> </header> <div class=md-container data-md-component=container> <main class=md-main data-md-component=main> <div class="md-main__inner md-grid"> <div class="md-sidebar md-sidebar--primary" data-md-component=sidebar data-md-type=navigation> <div class=md-sidebar__scrollwrap> <div class=md-sidebar__inner> <nav class="md-nav md-nav--primary md-nav--lifted" aria-label=Navigation data-md-level=0> <label class=md-nav__title for=__drawer> <a href=../.. title="Ingress-Nginx Controller" class="md-nav__button md-logo" aria-label="Ingress-Nginx Controller" data-md-component=logo> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 24 24"><path d="M12 8a3 3 0 0 0 3-3 3 3 0 0 0-3-3 3 3 0 0 0-3 3 3 3 0 0 0 3 3m0 3.54C9.64 9.35 6.5 8 3 8v11c3.5 0 6.64 1.35 9 3.54 2.36-2.19 5.5-3.54 9-3.54V8c-3.5 0-6.64 1.35-9 3.54Z"/></svg> </a> Ingress-Nginx Controller </label> <div class=md-nav__source> <a href=https://github.com/kubernetes/ingress-nginx title="Go to repository" class=md-source data-md-component=source> <div class="md-source__icon md-icon"> <svg xmlns=http://www.w3.org/2000/svg viewbox="0 0 448 512"><!-- Font Awesome Free 6.4.2 by @fontawesome - https://fontawesome.com License - https://fontawesome.com/license/free (Icons: CC BY 4.0, Fonts: SIL OFL 1.1, Code: MIT License) Copyright 2023 Fonticons, Inc.--><path d="M439.55 236.05 244 40.45a28.87 28.87 0 0 0-40.81 0l-40.66 40.63 51.52 51.52c27.06-9.14 52.68 16.77 43.39 43.68l49.66 49.66c34.23-11.8 61.18 31 35.47 56.69-26.49 26.49-70.21-2.87-56-37.34L240.22 199v121.85c25.3 12.54 22.26 41.85 9.08 55a34.34 34.34 0 0 1-48.55 0c-17.57-17.6-11.07-46.91 11.25-56v-123c-20.8-8.51-24.6-30.74-18.64-45L142.57 101 8.45 235.14a28.86 28.86 0 0 0 0 40.81l195.61 195.6a28.86 28.86 0 0 0 40.8 0l194.69-194.69a28.86 28.86 0 0 0 0-40.81z"/></svg> </div> <div class=md-source__repository> kubernetes/ingress-nginx </div> </a> </div> <ul class=md-nav__list data-md-scrollfix> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_1> <label class=md-nav__link for=__nav_1 id=__nav_1_label tabindex> <span class=md-ellipsis> Welcome </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=1 aria-labelledby=__nav_1_label aria-expanded=false> <label class=md-nav__title for=__nav_1> <span class="md-nav__icon md-icon"></span> Welcome </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../.. class=md-nav__link> <span class=md-ellipsis> Welcome </span> </a> </li> <li class=md-nav__item> <a href=../../how-it-works/ class=md-nav__link> <span class=md-ellipsis> How it works </span> </a> </li> <li class=md-nav__item> <a href=../../troubleshooting/ class=md-nav__link> <span class=md-ellipsis> Troubleshooting </span> </a> </li> <li class=md-nav__item> <a href=../../kubectl-plugin/ class=md-nav__link> <span class=md-ellipsis> kubectl plugin </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_2> <label class=md-nav__link for=__nav_2 id=__nav_2_label tabindex> <span class=md-ellipsis> Deployment </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=1 aria-labelledby=__nav_2_label aria-expanded=false> <label class=md-nav__title for=__nav_2> <span class="md-nav__icon md-icon"></span> Deployment </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../deploy/ class=md-nav__link> <span class=md-ellipsis> Installation Guide </span> </a> </li> <li class=md-nav__item> <a href=../../deploy/baremetal/ class=md-nav__link> <span class=md-ellipsis> Bare-metal considerations </span> </a> </li> <li class=md-nav__item> <a href=../../deploy/rbac/ class=md-nav__link> <span class=md-ellipsis> Role Based Access Control (RBAC) </span> </a> </li> <li class=md-nav__item> <a href=../../deploy/upgrade/ class=md-nav__link> <span class=md-ellipsis> Upgrade </span> </a> </li> <li class=md-nav__item> <a href=../../deploy/hardening-guide/ class=md-nav__link> <span class=md-ellipsis> Hardening guide </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_3> <label class=md-nav__link for=__nav_3 id=__nav_3_label tabindex> <span class=md-ellipsis> User Guide </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=1 aria-labelledby=__nav_3_label aria-expanded=false> <label class=md-nav__title for=__nav_3> <span class="md-nav__icon md-icon"></span> User Guide </label> <ul class=md-nav__list data-md-scrollfix> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_3_1> <label class=md-nav__link for=__nav_3_1 id=__nav_3_1_label tabindex> <span class=md-ellipsis> NGINX Configuration </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_3_1_label aria-expanded=false> <label class=md-nav__title for=__nav_3_1> <span class="md-nav__icon md-icon"></span> NGINX Configuration </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../user-guide/nginx-configuration/ class=md-nav__link> <span class=md-ellipsis> Introduction </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/basic-usage/ class=md-nav__link> <span class=md-ellipsis> Basic usage </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/nginx-configuration/annotations/ class=md-nav__link> <span class=md-ellipsis> Annotations </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/nginx-configuration/annotations-risk/ class=md-nav__link> <span class=md-ellipsis> Annotations Risks </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/nginx-configuration/configmap/ class=md-nav__link> <span class=md-ellipsis> ConfigMap </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/nginx-configuration/custom-template/ class=md-nav__link> <span class=md-ellipsis> Custom NGINX template </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/nginx-configuration/log-format/ class=md-nav__link> <span class=md-ellipsis> Log format </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../../user-guide/cli-arguments/ class=md-nav__link> <span class=md-ellipsis> Command line arguments </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/custom-errors/ class=md-nav__link> <span class=md-ellipsis> Custom errors </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/default-backend/ class=md-nav__link> <span class=md-ellipsis> Default backend </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/exposing-tcp-udp-services/ class=md-nav__link> <span class=md-ellipsis> Exposing TCP and UDP services </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/fcgi-services/ class=md-nav__link> <span class=md-ellipsis> Exposing FCGI services </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/ingress-path-matching/ class=md-nav__link> <span class=md-ellipsis> Regular expressions in paths </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/external-articles/ class=md-nav__link> <span class=md-ellipsis> External Articles </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/miscellaneous/ class=md-nav__link> <span class=md-ellipsis> Miscellaneous </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/monitoring/ class=md-nav__link> <span class=md-ellipsis> Prometheus and Grafana installation </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/multiple-ingress/ class=md-nav__link> <span class=md-ellipsis> Multiple Ingress controllers </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/tls/ class=md-nav__link> <span class=md-ellipsis> TLS/HTTPS </span> </a> </li> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_3_13> <label class=md-nav__link for=__nav_3_13 id=__nav_3_13_label tabindex> <span class=md-ellipsis> Third party addons </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_3_13_label aria-expanded=false> <label class=md-nav__title for=__nav_3_13> <span class="md-nav__icon md-icon"></span> Third party addons </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../user-guide/third-party-addons/modsecurity/ class=md-nav__link> <span class=md-ellipsis> ModSecurity Web Application Firewall </span> </a> </li> <li class=md-nav__item> <a href=../../user-guide/third-party-addons/opentelemetry/ class=md-nav__link> <span class=md-ellipsis> OpenTelemetry </span> </a> </li> </ul> </nav> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4> <label class=md-nav__link for=__nav_4 id=__nav_4_label tabindex> <span class=md-ellipsis> Examples </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=1 aria-labelledby=__nav_4_label aria-expanded=false> <label class=md-nav__title for=__nav_4> <span class="md-nav__icon md-icon"></span> Examples </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../examples/ class=md-nav__link> <span class=md-ellipsis> Introduction </span> </a> </li> <li class=md-nav__item> <a href=../../examples/PREREQUISITES/ class=md-nav__link> <span class=md-ellipsis> Prerequisites </span> </a> </li> <li class=md-nav__item> <a href=../../examples/affinity/cookie/ class=md-nav__link> <span class=md-ellipsis> Sticky Sessions </span> </a> </li> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_4> <label class=md-nav__link for=__nav_4_4 id=__nav_4_4_label tabindex> <span class=md-ellipsis> Auth </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_4_4_label aria-expanded=false> <label class=md-nav__title for=__nav_4_4> <span class="md-nav__icon md-icon"></span> Auth </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../examples/auth/basic/ class=md-nav__link> <span class=md-ellipsis> Basic Authentication </span> </a> </li> <li class=md-nav__item> <a href=../../examples/auth/client-certs/ class=md-nav__link> <span class=md-ellipsis> Client Certificate Authentication </span> </a> </li> <li class=md-nav__item> <a href=../../examples/auth/external-auth/ class=md-nav__link> <span class=md-ellipsis> External Basic Authentication </span> </a> </li> <li class=md-nav__item> <a href=../../examples/auth/oauth-external-auth/ class=md-nav__link> <span class=md-ellipsis> External OAUTH Authentication </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_4_5> <label class=md-nav__link for=__nav_4_5 id=__nav_4_5_label tabindex> <span class=md-ellipsis> Customization </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=2 aria-labelledby=__nav_4_5_label aria-expanded=false> <label class=md-nav__title for=__nav_4_5> <span class="md-nav__icon md-icon"></span> Customization </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../examples/customization/configuration-snippets/ class=md-nav__link> <span class=md-ellipsis> Configuration Snippets </span> </a> </li> <li class=md-nav__item> <a href=../../examples/customization/custom-configuration/ class=md-nav__link> <span class=md-ellipsis> Custom Configuration </span> </a> </li> <li class=md-nav__item> <a href=../../examples/customization/custom-errors/ class=md-nav__link> <span class=md-ellipsis> Custom Errors </span> </a> </li> <li class=md-nav__item> <a href=../../examples/customization/custom-headers/ class=md-nav__link> <span class=md-ellipsis> Custom Headers </span> </a> </li> <li class=md-nav__item> <a href=../../examples/customization/external-auth-headers/ class=md-nav__link> <span class=md-ellipsis> External authentication </span> </a> </li> <li class=md-nav__item> <a href=../../examples/customization/ssl-dh-param/ class=md-nav__link> <span class=md-ellipsis> Custom DH parameters for perfect forward secrecy </span> </a> </li> <li class=md-nav__item> <a href=../../examples/customization/sysctl/ class=md-nav__link> <span class=md-ellipsis> Sysctl tuning </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../../examples/docker-registry/ class=md-nav__link> <span class=md-ellipsis> Docker registry </span> </a> </li> <li class=md-nav__item> <a href=../../examples/grpc/ class=md-nav__link> <span class=md-ellipsis> gRPC </span> </a> </li> <li class=md-nav__item> <a href=../../examples/multi-tls/ class=md-nav__link> <span class=md-ellipsis> Multi TLS certificate termination </span> </a> </li> <li class=md-nav__item> <a href=../../examples/rewrite/ class=md-nav__link> <span class=md-ellipsis> Rewrite </span> </a> </li> <li class=md-nav__item> <a href=../../examples/static-ip/ class=md-nav__link> <span class=md-ellipsis> Static IPs </span> </a> </li> <li class=md-nav__item> <a href=../../examples/tls-termination/ class=md-nav__link> <span class=md-ellipsis> TLS termination </span> </a> </li> <li class=md-nav__item> <a href=../../examples/openpolicyagent/ class=md-nav__link> <span class=md-ellipsis> Open Policy Agent rules </span> </a> </li> <li class=md-nav__item> <a href=../../examples/canary/ class=md-nav__link> <span class=md-ellipsis> Canary Deployments </span> </a> </li> </ul> </nav> </li> <li class="md-nav__item md-nav__item--section md-nav__item--nested"> <input class="md-nav__toggle md-toggle " type=checkbox id=__nav_5> <label class=md-nav__link for=__nav_5 id=__nav_5_label tabindex> <span class=md-ellipsis> Developer Guide </span> <span class="md-nav__icon md-icon"></span> </label> <nav class=md-nav data-md-level=1 aria-labelledby=__nav_5_label aria-expanded=false> <label class=md-nav__title for=__nav_5> <span class="md-nav__icon md-icon"></span> Developer Guide </label> <ul class=md-nav__list data-md-scrollfix> <li class=md-nav__item> <a href=../../developer-guide/getting-started/ class=md-nav__link> <span class=md-ellipsis> Getting Started </span> </a> </li> <li class=md-nav__item> <a href=../../developer-guide/code-overview/ class=md-nav__link> <span class=md-ellipsis> Code Overview </span> </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=../../faq/ class=md-nav__link> <span class=md-ellipsis> FAQ </span> </a> </li> </ul> </nav> </div> </div> </div> <div class="md-sidebar md-sidebar--secondary" data-md-component=sidebar data-md-type=toc> <div class=md-sidebar__scrollwrap> <div class=md-sidebar__inner> <nav class="md-nav md-nav--secondary" aria-label="Table of contents"> <label class=md-nav__title for=__toc> <span class="md-nav__icon md-icon"></span> Table of contents </label> <ul class=md-nav__list data-md-component=toc data-md-scrollfix> <li class=md-nav__item> <a href=#table-of-contents class=md-nav__link> Table of Contents </a> </li> <li class=md-nav__item> <a href=#summary class=md-nav__link> Summary </a> </li> <li class=md-nav__item> <a href=#motivation class=md-nav__link> Motivation </a> <nav class=md-nav aria-label=Motivation> <ul class=md-nav__list> <li class=md-nav__item> <a href=#goals class=md-nav__link> Goals </a> </li> <li class=md-nav__item> <a href=#non-goals class=md-nav__link> Non-Goals </a> </li> </ul> </nav> </li> <li class=md-nav__item> <a href=#proposal class=md-nav__link> Proposal </a> </li> <li class=md-nav__item> <a href=#implementation-history class=md-nav__link> Implementation History </a> </li> <li class=md-nav__item> <a href=#drawbacks-optional class=md-nav__link> Drawbacks [optional] </a> </li> </ul> </nav> </div> </div> </div> <div class=md-content data-md-component=content> <article class="md-content__inner md-typeset"> <h1 id=availability-zone-aware-routing>Availability zone aware routing<a class=headerlink href=#availability-zone-aware-routing title="Permanent link"> ¶</a></h1> <h2 id=table-of-contents>Table of Contents<a class=headerlink href=#table-of-contents title="Permanent link"> ¶</a></h2> <!-- toc --> <ul> <li><a href=#availability-zone-aware-routing>Availability zone aware routing</a></li> <li><a href=#table-of-contents>Table of Contents</a></li> <li><a href=#summary>Summary</a></li> <li><a href=#motivation>Motivation</a><ul> <li><a href=#goals>Goals</a></li> <li><a href=#non-goals>Non-Goals</a></li> </ul> </li> <li><a href=#proposal>Proposal</a></li> <li><a href=#implementation-history>Implementation History</a></li> <li><a href=#drawbacks-optional>Drawbacks [optional]</a></li> </ul> <!-- /toc --> <h2 id=summary>Summary<a class=headerlink href=#summary title="Permanent link"> ¶</a></h2> <p>Teach ingress-nginx about availability zones where endpoints are running in. This way ingress-nginx pod will do its best to proxy to zone-local endpoint.</p> <h2 id=motivation>Motivation<a class=headerlink href=#motivation title="Permanent link"> ¶</a></h2> <p>When users run their services across multiple availability zones they usually pay for egress traffic between zones. Providers such as GCP, and Amazon EC2 usually charge extra for this feature. ingress-nginx when picking an endpoint to route request to does not consider whether the endpoint is in a different zone or the same one. That means it's at least equally likely that it will pick an endpoint from another zone and proxy the request to it. In this situation response from the endpoint to the ingress-nginx pod is considered inter-zone traffic and usually costs extra money.</p> <p>At the time of this writing, GCP charges $0.01 per GB of inter-zone egress traffic according to https://cloud.google.com/compute/network-pricing. According to <a href=https://web.archive.org/web/20201008160149/https://datapath.io/resources/blog/what-are-aws-data-transfer-costs-and-how-to-minimize-them/ >https://datapath.io/resources/blog/what-are-aws-data-transfer-costs-and-how-to-minimize-them/</a> Amazon also charges the same amount of money as GCP for cross-zone, egress traffic.</p> <p>This can be a lot of money depending on once's traffic. By teaching ingress-nginx about zones we can eliminate or at least decrease this cost.</p> <p>Arguably inter-zone network latency should also be better than cross-zone.</p> <h3 id=goals>Goals<a class=headerlink href=#goals title="Permanent link"> ¶</a></h3> <ul> <li>Given a regional cluster running ingress-nginx, ingress-nginx should do best-effort to pick a zone-local endpoint when proxying</li> <li>This should not impact canary feature</li> <li>ingress-nginx should be able to operate successfully if there are no zonal endpoints</li> </ul> <h3 id=non-goals>Non-Goals<a class=headerlink href=#non-goals title="Permanent link"> ¶</a></h3> <ul> <li>This feature inherently assumes that endpoints are distributed across zones in a way that they can handle all the traffic from ingress-nginx pod(s) in that zone</li> <li>This feature will be relying on https://kubernetes.io/docs/reference/kubernetes-api/labels-annotations-taints/#failure-domainbetakubernetesiozone, it is not this KEP's goal to support other cases</li> </ul> <h2 id=proposal>Proposal<a class=headerlink href=#proposal title="Permanent link"> ¶</a></h2> <p>The idea here is to have the controller part of ingress-nginx (1) detect what zone its current pod is running in and (2) detect the zone for every endpoint it knows about. After that, it will post that data as part of endpoints to Lua land. When picking an endpoint, the Lua balancer will try to pick zone-local endpoint first and if there is no zone-local endpoint then it will fall back to current behavior.</p> <p>Initially, this feature should be optional since it is going to make it harder to reason about the load balancing and not everyone might want that.</p> <p><strong>How does controller know what zone it runs in?</strong> We can have the pod spec pass the node name using downward API as an environment variable. Upon startup, the controller can get node details from the API based on the node name. Once the node details are obtained we can extract the zone from the <code>failure-domain.beta.kubernetes.io/zone</code> annotation. Then we can pass that value to Lua land through Nginx configuration when loading <code>lua_ingress.lua</code> module in <code>init_by_lua</code> phase.</p> <p><strong>How do we extract zones for endpoints?</strong> We can have the controller watch create and update events on nodes in the entire cluster and based on that keep the map of nodes to zones in the memory. And when we generate endpoints list, we can access node name using <code>.subsets.addresses[i].nodeName</code> and based on that fetch zone from the map in memory and store it as a field on the endpoint. <strong>This solution assumes <code>failure-domain.beta.kubernetes.io/zone</code></strong> annotation does not change until the end of the node's life. Otherwise, we have to watch update events as well on the nodes and that'll add even more overhead.</p> <p>Alternatively, we can get the list of nodes only when there's no node in the memory for the given node name. This is probably a better solution because then we would avoid watching for API changes on node resources. We can eagerly fetch all the nodes and build node name to zone mapping on start. From there on, it will sync during endpoint building in the main event loop if there's no existing entry for the node of an endpoint. This means an extra API call in case cluster has expanded.</p> <p><strong>How do we make sure we do our best to choose zone-local endpoint?</strong> This will be done on the Lua side. For every backend, we will initialize two balancer instances: (1) with all endpoints (2) with all endpoints corresponding to the current zone for the backend. Then given the request once we choose what backend needs to serve the request, we will first try to use a zonal balancer for that backend. If a zonal balancer does not exist (i.e. there's no zonal endpoint) then we will use a general balancer. In case of zonal outages, we assume that the readiness probe will fail and the controller will see no endpoints for the backend and therefore we will use a general balancer.</p> <p>We can enable the feature using a configmap setting. Doing it this way makes it easier to rollback in case of a problem.</p> <h2 id=implementation-history>Implementation History<a class=headerlink href=#implementation-history title="Permanent link"> ¶</a></h2> <ul> <li>initial version of KEP is shipped</li> <li>proposal and implementation details are done</li> </ul> <h2 id=drawbacks-optional>Drawbacks [optional]<a class=headerlink href=#drawbacks-optional title="Permanent link"> ¶</a></h2> <p>More load on the Kubernetes API server.</p> </article> </div> </div> </main> <footer class=md-footer> <div class="md-footer-meta md-typeset"> <div class="md-footer-meta__inner md-grid"> <div class=md-copyright> Made with <a href=https://squidfunk.github.io/mkdocs-material/ target=_blank rel=noopener> Material for MkDocs </a> </div> </div> </div> </footer> </div> <div class=md-dialog data-md-component=dialog> <div class="md-dialog__inner md-typeset"></div> </div> <script id=__config type=application/json>{"base": "../..", "features": ["navigation.tabs", "navigation.tabs.sticky", "navigation.instant", "navigation.sections"], "search": "../../assets/javascripts/workers/search.f886a092.min.js", "translations": {"clipboard.copied": "Copied to clipboard", "clipboard.copy": "Copy to clipboard", "search.result.more.one": "1 more on this page", "search.result.more.other": "# more on this page", "search.result.none": "No matching documents", "search.result.one": "1 matching document", "search.result.other": "# matching documents", "search.result.placeholder": "Type to start searching", "search.result.term.missing": "Missing", "select.version": "Select version"}}</script> <script src=../../assets/javascripts/bundle.aecac24b.min.js></script> </body> </html> |