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<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>8.9. Network Address Types</title><link rel="stylesheet" type="text/css" href="stylesheet.css" /><link rev="made" href="pgsql-docs@lists.postgresql.org" /><meta name="generator" content="DocBook XSL Stylesheets Vsnapshot" /><link rel="prev" href="datatype-geometric.html" title="8.8. Geometric Types" /><link rel="next" href="datatype-bit.html" title="8.10. Bit String Types" /></head><body id="docContent" class="container-fluid col-10"><div class="navheader"><table width="100%" summary="Navigation header"><tr><th colspan="5" align="center">8.9. Network Address Types</th></tr><tr><td width="10%" align="left"><a accesskey="p" href="datatype-geometric.html" title="8.8. Geometric Types">Prev</a> </td><td width="10%" align="left"><a accesskey="u" href="datatype.html" title="Chapter 8. Data Types">Up</a></td><th width="60%" align="center">Chapter 8. Data Types</th><td width="10%" align="right"><a accesskey="h" href="index.html" title="PostgreSQL 16.3 Documentation">Home</a></td><td width="10%" align="right"> <a accesskey="n" href="datatype-bit.html" title="8.10. Bit String Types">Next</a></td></tr></table><hr /></div><div class="sect1" id="DATATYPE-NET-TYPES"><div class="titlepage"><div><div><h2 class="title" style="clear: both">8.9. Network Address Types <a href="#DATATYPE-NET-TYPES" class="id_link">#</a></h2></div></div></div><div class="toc"><dl class="toc"><dt><span class="sect2"><a href="datatype-net-types.html#DATATYPE-INET">8.9.1. <code class="type">inet</code></a></span></dt><dt><span class="sect2"><a href="datatype-net-types.html#DATATYPE-CIDR">8.9.2. <code class="type">cidr</code></a></span></dt><dt><span class="sect2"><a href="datatype-net-types.html#DATATYPE-INET-VS-CIDR">8.9.3. <code class="type">inet</code> vs. <code class="type">cidr</code></a></span></dt><dt><span class="sect2"><a href="datatype-net-types.html#DATATYPE-MACADDR">8.9.4. <code class="type">macaddr</code></a></span></dt><dt><span class="sect2"><a href="datatype-net-types.html#DATATYPE-MACADDR8">8.9.5. <code class="type">macaddr8</code></a></span></dt></dl></div><a id="id-1.5.7.17.2" class="indexterm"></a><p> <span class="productname">PostgreSQL</span> offers data types to store IPv4, IPv6, and MAC addresses, as shown in <a class="xref" href="datatype-net-types.html#DATATYPE-NET-TYPES-TABLE" title="Table 8.21. Network Address Types">Table 8.21</a>. It is better to use these types instead of plain text types to store network addresses, because these types offer input error checking and specialized operators and functions (see <a class="xref" href="functions-net.html" title="9.12. Network Address Functions and Operators">Section 9.12</a>). </p><div class="table" id="DATATYPE-NET-TYPES-TABLE"><p class="title"><strong>Table 8.21. Network Address Types</strong></p><div class="table-contents"><table class="table" summary="Network Address Types" border="1"><colgroup><col class="col1" /><col class="col2" /><col class="col3" /></colgroup><thead><tr><th>Name</th><th>Storage Size</th><th>Description</th></tr></thead><tbody><tr><td><code class="type">cidr</code></td><td>7 or 19 bytes</td><td>IPv4 and IPv6 networks</td></tr><tr><td><code class="type">inet</code></td><td>7 or 19 bytes</td><td>IPv4 and IPv6 hosts and networks</td></tr><tr><td><code class="type">macaddr</code></td><td>6 bytes</td><td>MAC addresses</td></tr><tr><td><code class="type">macaddr8</code></td><td>8 bytes</td><td>MAC addresses (EUI-64 format)</td></tr></tbody></table></div></div><br class="table-break" /><p> When sorting <code class="type">inet</code> or <code class="type">cidr</code> data types, IPv4 addresses will always sort before IPv6 addresses, including IPv4 addresses encapsulated or mapped to IPv6 addresses, such as ::10.2.3.4 or ::ffff:10.4.3.2. </p><div class="sect2" id="DATATYPE-INET"><div class="titlepage"><div><div><h3 class="title">8.9.1. <code class="type">inet</code> <a href="#DATATYPE-INET" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.17.6.2" class="indexterm"></a><p> The <code class="type">inet</code> type holds an IPv4 or IPv6 host address, and optionally its subnet, all in one field. The subnet is represented by the number of network address bits present in the host address (the <span class="quote">“<span class="quote">netmask</span>”</span>). If the netmask is 32 and the address is IPv4, then the value does not indicate a subnet, only a single host. In IPv6, the address length is 128 bits, so 128 bits specify a unique host address. Note that if you want to accept only networks, you should use the <code class="type">cidr</code> type rather than <code class="type">inet</code>. </p><p> The input format for this type is <em class="replaceable"><code>address/y</code></em> where <em class="replaceable"><code>address</code></em> is an IPv4 or IPv6 address and <em class="replaceable"><code>y</code></em> is the number of bits in the netmask. If the <em class="replaceable"><code>/y</code></em> portion is omitted, the netmask is taken to be 32 for IPv4 or 128 for IPv6, so the value represents just a single host. On display, the <em class="replaceable"><code>/y</code></em> portion is suppressed if the netmask specifies a single host. </p></div><div class="sect2" id="DATATYPE-CIDR"><div class="titlepage"><div><div><h3 class="title">8.9.2. <code class="type">cidr</code> <a href="#DATATYPE-CIDR" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.17.7.2" class="indexterm"></a><p> The <code class="type">cidr</code> type holds an IPv4 or IPv6 network specification. Input and output formats follow Classless Internet Domain Routing conventions. The format for specifying networks is <em class="replaceable"><code>address/y</code></em> where <em class="replaceable"><code>address</code></em> is the network's lowest address represented as an IPv4 or IPv6 address, and <em class="replaceable"><code>y</code></em> is the number of bits in the netmask. If <em class="replaceable"><code>y</code></em> is omitted, it is calculated using assumptions from the older classful network numbering system, except it will be at least large enough to include all of the octets written in the input. It is an error to specify a network address that has bits set to the right of the specified netmask. </p><p> <a class="xref" href="datatype-net-types.html#DATATYPE-NET-CIDR-TABLE" title="Table 8.22. cidr Type Input Examples">Table 8.22</a> shows some examples. </p><div class="table" id="DATATYPE-NET-CIDR-TABLE"><p class="title"><strong>Table 8.22. <code class="type">cidr</code> Type Input Examples</strong></p><div class="table-contents"><table class="table" summary="cidr Type Input Examples" border="1"><colgroup><col /><col /><col /></colgroup><thead><tr><th><code class="type">cidr</code> Input</th><th><code class="type">cidr</code> Output</th><th><code class="literal"><code class="function">abbrev(<code class="type">cidr</code>)</code></code></th></tr></thead><tbody><tr><td>192.168.100.128/25</td><td>192.168.100.128/25</td><td>192.168.100.128/25</td></tr><tr><td>192.168/24</td><td>192.168.0.0/24</td><td>192.168.0/24</td></tr><tr><td>192.168/25</td><td>192.168.0.0/25</td><td>192.168.0.0/25</td></tr><tr><td>192.168.1</td><td>192.168.1.0/24</td><td>192.168.1/24</td></tr><tr><td>192.168</td><td>192.168.0.0/24</td><td>192.168.0/24</td></tr><tr><td>128.1</td><td>128.1.0.0/16</td><td>128.1/16</td></tr><tr><td>128</td><td>128.0.0.0/16</td><td>128.0/16</td></tr><tr><td>128.1.2</td><td>128.1.2.0/24</td><td>128.1.2/24</td></tr><tr><td>10.1.2</td><td>10.1.2.0/24</td><td>10.1.2/24</td></tr><tr><td>10.1</td><td>10.1.0.0/16</td><td>10.1/16</td></tr><tr><td>10</td><td>10.0.0.0/8</td><td>10/8</td></tr><tr><td>10.1.2.3/32</td><td>10.1.2.3/32</td><td>10.1.2.3/32</td></tr><tr><td>2001:4f8:3:ba::/64</td><td>2001:4f8:3:ba::/64</td><td>2001:4f8:3:ba/64</td></tr><tr><td>2001:4f8:3:ba:2e0:81ff:fe22:d1f1/128</td><td>2001:4f8:3:ba:2e0:81ff:fe22:d1f1/128</td><td>2001:4f8:3:ba:2e0:81ff:fe22:d1f1/128</td></tr><tr><td>::ffff:1.2.3.0/120</td><td>::ffff:1.2.3.0/120</td><td>::ffff:1.2.3/120</td></tr><tr><td>::ffff:1.2.3.0/128</td><td>::ffff:1.2.3.0/128</td><td>::ffff:1.2.3.0/128</td></tr></tbody></table></div></div><br class="table-break" /></div><div class="sect2" id="DATATYPE-INET-VS-CIDR"><div class="titlepage"><div><div><h3 class="title">8.9.3. <code class="type">inet</code> vs. <code class="type">cidr</code> <a href="#DATATYPE-INET-VS-CIDR" class="id_link">#</a></h3></div></div></div><p> The essential difference between <code class="type">inet</code> and <code class="type">cidr</code> data types is that <code class="type">inet</code> accepts values with nonzero bits to the right of the netmask, whereas <code class="type">cidr</code> does not. For example, <code class="literal">192.168.0.1/24</code> is valid for <code class="type">inet</code> but not for <code class="type">cidr</code>. </p><div class="tip"><h3 class="title">Tip</h3><p> If you do not like the output format for <code class="type">inet</code> or <code class="type">cidr</code> values, try the functions <code class="function">host</code>, <code class="function">text</code>, and <code class="function">abbrev</code>. </p></div></div><div class="sect2" id="DATATYPE-MACADDR"><div class="titlepage"><div><div><h3 class="title">8.9.4. <code class="type">macaddr</code> <a href="#DATATYPE-MACADDR" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.17.9.2" class="indexterm"></a><a id="id-1.5.7.17.9.3" class="indexterm"></a><p> The <code class="type">macaddr</code> type stores MAC addresses, known for example from Ethernet card hardware addresses (although MAC addresses are used for other purposes as well). Input is accepted in the following formats: </p><table border="0" summary="Simple list" class="simplelist"><tr><td><code class="literal">'08:00:2b:01:02:03'</code></td></tr><tr><td><code class="literal">'08-00-2b-01-02-03'</code></td></tr><tr><td><code class="literal">'08002b:010203'</code></td></tr><tr><td><code class="literal">'08002b-010203'</code></td></tr><tr><td><code class="literal">'0800.2b01.0203'</code></td></tr><tr><td><code class="literal">'0800-2b01-0203'</code></td></tr><tr><td><code class="literal">'08002b010203'</code></td></tr></table><p> These examples all specify the same address. Upper and lower case is accepted for the digits <code class="literal">a</code> through <code class="literal">f</code>. Output is always in the first of the forms shown. </p><p> IEEE Standard 802-2001 specifies the second form shown (with hyphens) as the canonical form for MAC addresses, and specifies the first form (with colons) as used with bit-reversed, MSB-first notation, so that 08-00-2b-01-02-03 = 10:00:D4:80:40:C0. This convention is widely ignored nowadays, and it is relevant only for obsolete network protocols (such as Token Ring). PostgreSQL makes no provisions for bit reversal; all accepted formats use the canonical LSB order. </p><p> The remaining five input formats are not part of any standard. </p></div><div class="sect2" id="DATATYPE-MACADDR8"><div class="titlepage"><div><div><h3 class="title">8.9.5. <code class="type">macaddr8</code> <a href="#DATATYPE-MACADDR8" class="id_link">#</a></h3></div></div></div><a id="id-1.5.7.17.10.2" class="indexterm"></a><a id="id-1.5.7.17.10.3" class="indexterm"></a><p> The <code class="type">macaddr8</code> type stores MAC addresses in EUI-64 format, known for example from Ethernet card hardware addresses (although MAC addresses are used for other purposes as well). This type can accept both 6 and 8 byte length MAC addresses and stores them in 8 byte length format. MAC addresses given in 6 byte format will be stored in 8 byte length format with the 4th and 5th bytes set to FF and FE, respectively. Note that IPv6 uses a modified EUI-64 format where the 7th bit should be set to one after the conversion from EUI-48. The function <code class="function">macaddr8_set7bit</code> is provided to make this change. Generally speaking, any input which is comprised of pairs of hex digits (on byte boundaries), optionally separated consistently by one of <code class="literal">':'</code>, <code class="literal">'-'</code> or <code class="literal">'.'</code>, is accepted. The number of hex digits must be either 16 (8 bytes) or 12 (6 bytes). Leading and trailing whitespace is ignored. The following are examples of input formats that are accepted: </p><table border="0" summary="Simple list" class="simplelist"><tr><td><code class="literal">'08:00:2b:01:02:03:04:05'</code></td></tr><tr><td><code class="literal">'08-00-2b-01-02-03-04-05'</code></td></tr><tr><td><code class="literal">'08002b:0102030405'</code></td></tr><tr><td><code class="literal">'08002b-0102030405'</code></td></tr><tr><td><code class="literal">'0800.2b01.0203.0405'</code></td></tr><tr><td><code class="literal">'0800-2b01-0203-0405'</code></td></tr><tr><td><code class="literal">'08002b01:02030405'</code></td></tr><tr><td><code class="literal">'08002b0102030405'</code></td></tr></table><p> These examples all specify the same address. Upper and lower case is accepted for the digits <code class="literal">a</code> through <code class="literal">f</code>. Output is always in the first of the forms shown. </p><p> The last six input formats shown above are not part of any standard. </p><p> To convert a traditional 48 bit MAC address in EUI-48 format to modified EUI-64 format to be included as the host portion of an IPv6 address, use <code class="function">macaddr8_set7bit</code> as shown: </p><pre class="programlisting"> SELECT macaddr8_set7bit('08:00:2b:01:02:03'); <code class="computeroutput"> macaddr8_set7bit ------------------------- 0a:00:2b:ff:fe:01:02:03 (1 row) </code> </pre><p> </p></div></div><div class="navfooter"><hr /><table width="100%" summary="Navigation footer"><tr><td width="40%" align="left"><a accesskey="p" href="datatype-geometric.html" title="8.8. Geometric Types">Prev</a> </td><td width="20%" align="center"><a accesskey="u" href="datatype.html" title="Chapter 8. Data Types">Up</a></td><td width="40%" align="right"> <a accesskey="n" href="datatype-bit.html" title="8.10. 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