50 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			XML
		
	
	
	
	
	
			
		
		
	
	
			50 lines
		
	
	
		
			1.8 KiB
		
	
	
	
		
			XML
		
	
	
	
	
	
<section  xmlns="http://docbook.org/ns/docbook"
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          xmlns:xlink="http://www.w3.org/1999/xlink"
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          xmlns:xi="http://www.w3.org/2001/XInclude"
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          version="5.0"
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          xml:id="sec-container-networking">
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<title>Container Networking</title>
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<para>When you create a container using <literal>nixos-container
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create</literal>, it gets it own private IPv4 address in the range
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<literal>10.233.0.0/16</literal>. You can get the container’s IPv4
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address as follows:
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<screen>
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$ nixos-container show-ip foo
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10.233.4.2
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$ ping -c1 10.233.4.2
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64 bytes from 10.233.4.2: icmp_seq=1 ttl=64 time=0.106 ms
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</screen>
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</para>
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<para>Networking is implemented using a pair of virtual Ethernet
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devices. The network interface in the container is called
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<literal>eth0</literal>, while the matching interface in the host is
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called <literal>ve-<replaceable>container-name</replaceable></literal>
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(e.g., <literal>ve-foo</literal>).  The container has its own network
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namespace and the <literal>CAP_NET_ADMIN</literal> capability, so it
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can perform arbitrary network configuration such as setting up
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firewall rules, without affecting or having access to the host’s
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network.</para>
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<para>By default, containers cannot talk to the outside network. If
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you want that, you should set up Network Address Translation (NAT)
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rules on the host to rewrite container traffic to use your external
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IP address. This can be accomplished using the following configuration
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on the host:
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<programlisting>
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networking.nat.enable = true;
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networking.nat.internalInterfaces = ["ve-+"];
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networking.nat.externalInterface = "eth0";
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</programlisting>
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where <literal>eth0</literal> should be replaced with the desired
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external interface. Note that <literal>ve-+</literal> is a wildcard
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that matches all container interfaces.</para>
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</section> |