mirror of
https://github.com/linkedin/school-of-sre
synced 2026-01-08 17:48:02 +00:00
910 lines
23 KiB
HTML
910 lines
23 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 rel="shortcut icon" href="../../img/favicon.ico">
|
||
<meta name="generator" content="mkdocs-1.1.2, mkdocs-material-6.1.5">
|
||
|
||
|
||
|
||
<title>Routing and Conclusion - SchoolOfSRE</title>
|
||
|
||
|
||
|
||
<link rel="stylesheet" href="../../assets/stylesheets/main.21aed14c.min.css">
|
||
|
||
|
||
<link rel="stylesheet" href="../../assets/stylesheets/palette.196e0c26.min.css">
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<link href="https://fonts.gstatic.com" rel="preconnect" crossorigin>
|
||
<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Roboto:300,400,400i,700%7CRoboto+Mono&display=fallback">
|
||
<style>body,input{font-family:"Roboto",-apple-system,BlinkMacSystemFont,Helvetica,Arial,sans-serif}code,kbd,pre{font-family:"Roboto Mono",SFMono-Regular,Consolas,Menlo,monospace}</style>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
</head>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<body dir="ltr" data-md-color-scheme="" data-md-color-primary="none" data-md-color-accent="none">
|
||
|
||
|
||
<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="#ip-routing-and-data-link-layer" class="md-skip">
|
||
Skip to content
|
||
</a>
|
||
|
||
</div>
|
||
<div data-md-component="announce">
|
||
|
||
</div>
|
||
|
||
|
||
|
||
<header class="md-header" data-md-component="header">
|
||
<nav class="md-header-nav md-grid" aria-label="Header">
|
||
<a href="../.." title="SchoolOfSRE" class="md-header-nav__button md-logo" aria-label="SchoolOfSRE">
|
||
|
||
<img src="../../img/sos.png" alt="logo">
|
||
|
||
</a>
|
||
<label class="md-header-nav__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-nav__title" data-md-component="header-title">
|
||
|
||
<div class="md-header-nav__ellipsis">
|
||
<span class="md-header-nav__topic md-ellipsis">
|
||
SchoolOfSRE
|
||
</span>
|
||
<span class="md-header-nav__topic md-ellipsis">
|
||
|
||
Routing and Conclusion
|
||
|
||
</span>
|
||
</div>
|
||
|
||
</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="navigation">
|
||
<div class="md-sidebar__scrollwrap">
|
||
<div class="md-sidebar__inner">
|
||
|
||
|
||
<nav class="md-nav md-nav--primary" aria-label="Navigation" data-md-level="0">
|
||
<label class="md-nav__title" for="__drawer">
|
||
<a href="../.." title="SchoolOfSRE" class="md-nav__button md-logo" aria-label="SchoolOfSRE">
|
||
|
||
<img src="../../img/sos.png" alt="logo">
|
||
|
||
</a>
|
||
SchoolOfSRE
|
||
</label>
|
||
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../.." class="md-nav__link">
|
||
Home
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--active md-nav__item--nested">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="nav-2" type="checkbox" id="nav-2" checked>
|
||
<label class="md-nav__link" for="nav-2">
|
||
Fundamentals Series
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
<nav class="md-nav" aria-label="Fundamentals Series" data-md-level="1">
|
||
<label class="md-nav__title" for="nav-2">
|
||
<span class="md-nav__icon md-icon"></span>
|
||
Fundamentals Series
|
||
</label>
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--nested">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="nav-2-1" type="checkbox" id="nav-2-1" >
|
||
<label class="md-nav__link" for="nav-2-1">
|
||
Git
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
<nav class="md-nav" aria-label="Git" data-md-level="2">
|
||
<label class="md-nav__title" for="nav-2-1">
|
||
<span class="md-nav__icon md-icon"></span>
|
||
Git
|
||
</label>
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../git/git-basics/" class="md-nav__link">
|
||
Git Basics
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../git/branches/" class="md-nav__link">
|
||
Working With Branches
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../git/github-hooks/" class="md-nav__link">
|
||
Github and Hooks
|
||
</a>
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--active md-nav__item--nested">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="nav-2-2" type="checkbox" id="nav-2-2" checked>
|
||
<label class="md-nav__link" for="nav-2-2">
|
||
Linux Networking
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
<nav class="md-nav" aria-label="Linux Networking" data-md-level="2">
|
||
<label class="md-nav__title" for="nav-2-2">
|
||
<span class="md-nav__icon md-icon"></span>
|
||
Linux Networking
|
||
</label>
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../intro/" class="md-nav__link">
|
||
Introduction
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../dns/" class="md-nav__link">
|
||
DNS
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../udp/" class="md-nav__link">
|
||
UDP
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../http/" class="md-nav__link">
|
||
HTTP
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../tcp/" class="md-nav__link">
|
||
TCP
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--active">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="toc" type="checkbox" id="__toc">
|
||
|
||
|
||
|
||
|
||
<label class="md-nav__link md-nav__link--active" for="__toc">
|
||
Routing and Conclusion
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
|
||
<a href="./" class="md-nav__link md-nav__link--active">
|
||
Routing and Conclusion
|
||
</a>
|
||
|
||
|
||
<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-scrollfix>
|
||
|
||
<li class="md-nav__item">
|
||
<a href="#applications-in-sre-role" class="md-nav__link">
|
||
Applications in SRE role
|
||
</a>
|
||
|
||
</li>
|
||
|
||
<li class="md-nav__item">
|
||
<a href="#conclusion" class="md-nav__link">
|
||
Conclusion
|
||
</a>
|
||
|
||
</li>
|
||
|
||
</ul>
|
||
|
||
</nav>
|
||
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--nested">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="nav-3" type="checkbox" id="nav-3" >
|
||
<label class="md-nav__link" for="nav-3">
|
||
Python and Web
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
<nav class="md-nav" aria-label="Python and Web" data-md-level="1">
|
||
<label class="md-nav__title" for="nav-3">
|
||
<span class="md-nav__icon md-icon"></span>
|
||
Python and Web
|
||
</label>
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../python_web/intro/" class="md-nav__link">
|
||
Introduction
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../python_web/python-concepts/" class="md-nav__link">
|
||
Some Python Concepts
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../python_web/python-web-flask/" class="md-nav__link">
|
||
Python, Web and Flask
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../python_web/url-shorten-app/" class="md-nav__link">
|
||
The URL Shortening App
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../python_web/sre-conclusion/" class="md-nav__link">
|
||
SRE Aspects of The App and Conclusion
|
||
</a>
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--nested">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="nav-4" type="checkbox" id="nav-4" >
|
||
<label class="md-nav__link" for="nav-4">
|
||
Systems Design
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
<nav class="md-nav" aria-label="Systems Design" data-md-level="1">
|
||
<label class="md-nav__title" for="nav-4">
|
||
<span class="md-nav__icon md-icon"></span>
|
||
Systems Design
|
||
</label>
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../systems_design/intro/" class="md-nav__link">
|
||
Introduction
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../systems_design/scalability/" class="md-nav__link">
|
||
Scalability
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../systems_design/availability/" class="md-nav__link">
|
||
Availability
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../systems_design/fault-tolerance/" class="md-nav__link">
|
||
Fault Tolerance
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../systems_design/conclusion/" class="md-nav__link">
|
||
Conclusion
|
||
</a>
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--nested">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="nav-5" type="checkbox" id="nav-5" >
|
||
<label class="md-nav__link" for="nav-5">
|
||
Data
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
<nav class="md-nav" aria-label="Data" data-md-level="1">
|
||
<label class="md-nav__title" for="nav-5">
|
||
<span class="md-nav__icon md-icon"></span>
|
||
Data
|
||
</label>
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--nested">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="nav-5-1" type="checkbox" id="nav-5-1" >
|
||
<label class="md-nav__link" for="nav-5-1">
|
||
Big Data
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
<nav class="md-nav" aria-label="Big Data" data-md-level="2">
|
||
<label class="md-nav__title" for="nav-5-1">
|
||
<span class="md-nav__icon md-icon"></span>
|
||
Big Data
|
||
</label>
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../big_data/intro/" class="md-nav__link">
|
||
Introduction
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../big_data/overview/" class="md-nav__link">
|
||
Overview of Big Data
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../big_data/usage/" class="md-nav__link">
|
||
Usage of Big Data techniques
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../big_data/evolution/" class="md-nav__link">
|
||
Evolution of Hadoop
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../big_data/architecture/" class="md-nav__link">
|
||
Architecture of Hadoop
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../big_data/tasks/" class="md-nav__link">
|
||
Tasks and conclusion
|
||
</a>
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item md-nav__item--nested">
|
||
|
||
<input class="md-nav__toggle md-toggle" data-md-toggle="nav-6" type="checkbox" id="nav-6" >
|
||
<label class="md-nav__link" for="nav-6">
|
||
Security
|
||
<span class="md-nav__icon md-icon"></span>
|
||
</label>
|
||
<nav class="md-nav" aria-label="Security" data-md-level="1">
|
||
<label class="md-nav__title" for="nav-6">
|
||
<span class="md-nav__icon md-icon"></span>
|
||
Security
|
||
</label>
|
||
<ul class="md-nav__list" data-md-scrollfix>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../security/intro/" class="md-nav__link">
|
||
Introduction
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../security/fundamentals/" class="md-nav__link">
|
||
Fundamentals of Security
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../security/network_security/" class="md-nav__link">
|
||
Network Security
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../security/threats_attacks_defences/" class="md-nav__link">
|
||
Threat, Attacks & Defences
|
||
</a>
|
||
</li>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
<li class="md-nav__item">
|
||
<a href="../../security/writing_secure_code/" class="md-nav__link">
|
||
Writing Secure code
|
||
</a>
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</li>
|
||
|
||
|
||
</ul>
|
||
</nav>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
|
||
|
||
<div class="md-sidebar md-sidebar--secondary" data-md-component="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-scrollfix>
|
||
|
||
<li class="md-nav__item">
|
||
<a href="#applications-in-sre-role" class="md-nav__link">
|
||
Applications in SRE role
|
||
</a>
|
||
|
||
</li>
|
||
|
||
<li class="md-nav__item">
|
||
<a href="#conclusion" class="md-nav__link">
|
||
Conclusion
|
||
</a>
|
||
|
||
</li>
|
||
|
||
</ul>
|
||
|
||
</nav>
|
||
</div>
|
||
</div>
|
||
</div>
|
||
|
||
|
||
<div class="md-content">
|
||
<article class="md-content__inner md-typeset">
|
||
|
||
|
||
|
||
<h1 id="ip-routing-and-data-link-layer">IP Routing and Data Link Layer</h1>
|
||
<p>We will dig how packets that leave the client reach the server and vice versa. When the packet reaches the IP layer, the transport layer populates source port, destination port. IP/Network layer populates destination IP(discovered from DNS) and then looks up the route to the destination IP on the routing table. </p>
|
||
<pre><code class="language-bash">#Linux route -n command gives the default routing table
|
||
route -n
|
||
</code></pre>
|
||
<pre><code class="language-bash">Kernel IP routing table
|
||
Destination Gateway Genmask Flags Metric Ref Use Iface
|
||
0.0.0.0 172.17.0.1 0.0.0.0 UG 0 0 0 eth0
|
||
172.17.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0
|
||
</code></pre>
|
||
<p>Here the destination IP is bitwise AND’d with the Genmask and if the answer is the destination part of the table then that gateway and interface is picked for routing. Here linkedin.com’s IP 108.174.10.10 is AND’d with 255.255.255.0 and the answer we get is 108.174.10.0 which doesn’t match with any destination in the routing table. Then Linux does an AND of destination IP with 0.0.0.0 and we get 0.0.0.0. This answer matches the default row</p>
|
||
<p>Routing table is processed in the order of more octets of 1 set in genmask and genmask 0.0.0.0 is the default route if nothing matches.
|
||
At the end of this operation Linux figured out that the packet has to be sent to next hop 172.17.0.1 via eth0. The source IP of the packet will be set as the IP of interface eth0.
|
||
Now to send the packet to 172.17.0.1 linux has to figure out the MAC address of 172.17.0.1. MAC address is figured by looking at the internal arp cache which stores translation between IP address and MAC address. If there is a cache miss, Linux broadcasts ARP request within the internal network asking who has 172.17.0.1. The owner of the IP sends an ARP response which is cached by the kernel and the kernel sends the packet to the gateway by setting Source mac address as mac address of eth0 and destination mac address of 172.17.0.1 which we got just now. Similar routing lookup process is followed in each hop till the packet reaches the actual server. Transport layer and layers above it come to play only at end servers. During intermediate hops only till the IP/Network layer is involved.</p>
|
||
<p><img alt="Screengrab for above explanation" src="../images/arp.gif" /></p>
|
||
<p>One weird gateway we saw in the routing table is 0.0.0.0. This gateway means no Layer3(Network layer) hop is needed to send the packet. Both source and destination are in the same network. Kernel has to figure out the mac of the destination and populate source and destination mac appropriately and send the packet out so that it reaches the destination without any Layer3 hop in the middle</p>
|
||
<p>As we followed in other modules, lets complete this session with SRE usecases</p>
|
||
<h2 id="applications-in-sre-role">Applications in SRE role</h2>
|
||
<ol>
|
||
<li>Generally the routing table is populated by DHCP and playing around is not a good practice. There can be reasons where one has to play around the routing table but take that path only when it's absolutely necessary</li>
|
||
<li>Understanding error messages better like, “No route to host” error can mean mac address of the destination host is not found and it can mean the destination host is down </li>
|
||
<li>On rare cases looking at the ARP table can help us understand if there is a IP conflict where same IP is assigned to two hosts by mistake and this is causing unexpected behavior</li>
|
||
</ol>
|
||
<h2 id="conclusion">Conclusion</h2>
|
||
<p>With this we have traversed through the TCP/IP stack completely. We hope there will be a different perspective when one opens any website in the browser post the course. </p>
|
||
<p>During the course we have also dissected what are common tasks in this pipeline which falls under the ambit of SRE.</p>
|
||
<h1 id="post-training-exercises">Post Training Exercises</h1>
|
||
<ol>
|
||
<li>Setup own DNS resolver in the dev environment which acts as an authoritative DNS server for example.com and forwarder for other domains. Update resolv.conf to use the new DNS resolver running in localhost</li>
|
||
<li>Set up a site dummy.example.com in localhost and run a webserver with a self signed certificate. Update the trusted CAs or pass self signed CA’s public key as a parameter so that curl https://dummy.example.com -v works properly without self signed cert warning</li>
|
||
<li>Update the routing table to use another host(container/VM) in the same network as a gateway for 8.8.8.8/32 and run ping 8.8.8.8. Do the packet capture on the new gateway to see L3 hop is working as expected(might need to disable icmp_redirect)</li>
|
||
</ol>
|
||
|
||
|
||
|
||
|
||
|
||
|
||
|
||
</article>
|
||
</div>
|
||
</div>
|
||
</main>
|
||
|
||
|
||
<footer class="md-footer">
|
||
|
||
<div class="md-footer-nav">
|
||
<nav class="md-footer-nav__inner md-grid" aria-label="Footer">
|
||
|
||
<a href="../tcp/" class="md-footer-nav__link md-footer-nav__link--prev" rel="prev">
|
||
<div class="md-footer-nav__button md-icon">
|
||
<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>
|
||
</div>
|
||
<div class="md-footer-nav__title">
|
||
<div class="md-ellipsis">
|
||
<span class="md-footer-nav__direction">
|
||
Previous
|
||
</span>
|
||
TCP
|
||
</div>
|
||
</div>
|
||
</a>
|
||
|
||
|
||
<a href="../../python_web/intro/" class="md-footer-nav__link md-footer-nav__link--next" rel="next">
|
||
<div class="md-footer-nav__title">
|
||
<div class="md-ellipsis">
|
||
<span class="md-footer-nav__direction">
|
||
Next
|
||
</span>
|
||
Introduction
|
||
</div>
|
||
</div>
|
||
<div class="md-footer-nav__button md-icon">
|
||
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 24 24"><path d="M4 11v2h12l-5.5 5.5 1.42 1.42L19.84 12l-7.92-7.92L10.5 5.5 16 11H4z"/></svg>
|
||
</div>
|
||
</a>
|
||
|
||
</nav>
|
||
</div>
|
||
|
||
<div class="md-footer-meta md-typeset">
|
||
<div class="md-footer-meta__inner md-grid">
|
||
<div class="md-footer-copyright">
|
||
|
||
Made with
|
||
<a href="https://squidfunk.github.io/mkdocs-material/" target="_blank" rel="noopener">
|
||
Material for MkDocs
|
||
</a>
|
||
</div>
|
||
|
||
</div>
|
||
</div>
|
||
</footer>
|
||
|
||
</div>
|
||
|
||
<script src="../../assets/javascripts/vendor.7e0ee788.min.js"></script>
|
||
<script src="../../assets/javascripts/bundle.b3a72adc.min.js"></script><script id="__lang" type="application/json">{"clipboard.copy": "Copy to clipboard", "clipboard.copied": "Copied to clipboard", "search.config.lang": "en", "search.config.pipeline": "trimmer, stopWordFilter", "search.config.separator": "[\\s\\-]+", "search.placeholder": "Search", "search.result.placeholder": "Type to start searching", "search.result.none": "No matching documents", "search.result.one": "1 matching document", "search.result.other": "# matching documents", "search.result.more.one": "1 more on this page", "search.result.more.other": "# more on this page", "search.result.term.missing": "Missing"}</script>
|
||
|
||
<script>
|
||
app = initialize({
|
||
base: "../..",
|
||
features: [],
|
||
search: Object.assign({
|
||
worker: "../../assets/javascripts/worker/search.4ac00218.min.js"
|
||
}, typeof search !== "undefined" && search)
|
||
})
|
||
</script>
|
||
|
||
|
||
</body>
|
||
</html> |