{"id":563,"date":"2020-10-26T19:44:28","date_gmt":"2020-10-26T19:44:28","guid":{"rendered":"https:\/\/dft.wiki\/?p=563"},"modified":"2021-02-23T16:59:06","modified_gmt":"2021-02-23T16:59:06","slug":"nat-type-port-address-translation-pat-on-cisco-devices","status":"publish","type":"post","link":"https:\/\/dft.wiki\/?p=563","title":{"rendered":"NAT type Port Address Translation (PAT) on Cisco Devices"},"content":{"rendered":"<p>There are 3 types of NAT:<\/p>\n<ul>\n<li><strong>Static<\/strong> NAT &#8211; Translates a private to a public address (1-to-1).<\/li>\n<li><strong>Dynamic<\/strong> NAT &#8211; Translates a pool of private to a pool of public addresses (many-to-many).<\/li>\n<li>NAT <strong>Overload<\/strong> (or <strong>PAT<\/strong>) &#8211; Translates many private IPs over just one public IP (many-to-1).<\/li>\n<\/ul>\n<p>Define the inside interface:<\/p>\n<pre>int g0\/0\r\nip nat inside<\/pre>\n<p>Define the outside interface:<\/p>\n<pre>int g0\/1\r\nip nat outside<\/pre>\n<p>Creating the Access-List that will allow the translations <strong>many-to-one<\/strong>:<\/p>\n<pre>ip access-list standard USERS\r\npermit 10.1.1.0 0.0.0.255\r\nip nat inside source list USERS int g0\/1 <strong>overload<\/strong><\/pre>\n<p>Note: the access-list contains the private network address, and defined as the source, right next interface g0\/1 (not the public IP) is defined as the exit to the internet. Overload allows many internal addresses to be translated at the same time.<\/p>\n<p>Example for <strong>many-to-many<\/strong>:<\/p>\n<pre>ip access-list standard 1\r\n  permit 10.10.0.0 0.0.255.255\r\nip nat pool INTERNAL 192.168.1.129 192.168.1.254 netmask 255.255.255.128\r\nip nat inside source list 1 pool INTERNAL\r\nip route 0.0.0.0 0.0.0.0 172.16.1.1<\/pre>\n<p>If it is just <strong>one-to-one<\/strong> translation, avoid using access list and pool by issuing only:<\/p>\n<pre>ip nat inside source static 10.10.10.1 200.200.200.200<\/pre>\n<p>To see what is being translated:<\/p>\n<pre>do show ip nat translations\r\ndo show ip nat translations verbose<\/pre>\n","protected":false},"excerpt":{"rendered":"<p>There are 3 types of NAT: Static NAT &#8211; Translates a private to a public [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[],"class_list":["post-563","post","type-post","status-publish","format-standard","hentry","category-ccna"],"_links":{"self":[{"href":"https:\/\/dft.wiki\/index.php?rest_route=\/wp\/v2\/posts\/563","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dft.wiki\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dft.wiki\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dft.wiki\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dft.wiki\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=563"}],"version-history":[{"count":6,"href":"https:\/\/dft.wiki\/index.php?rest_route=\/wp\/v2\/posts\/563\/revisions"}],"predecessor-version":[{"id":1270,"href":"https:\/\/dft.wiki\/index.php?rest_route=\/wp\/v2\/posts\/563\/revisions\/1270"}],"wp:attachment":[{"href":"https:\/\/dft.wiki\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=563"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dft.wiki\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=563"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dft.wiki\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=563"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}