{"id":2139,"date":"2013-03-03T12:11:48","date_gmt":"2013-03-03T12:11:48","guid":{"rendered":"http:\/\/mccltd.net\/blog\/?p=2139"},"modified":"2015-03-03T12:22:21","modified_gmt":"2015-03-03T12:22:21","slug":"bgp-regular-expressions","status":"publish","type":"post","link":"http:\/\/darenmatthews.com\/blog\/?p=2139","title":{"rendered":"BGP Regular Expressions"},"content":{"rendered":"

+————-+—————————+
\n| Expression | Meaning |
\n|————-+—————————|
\n| .* | Anything |
\n|————-+—————————|
\n| ^$ | Locally originated routes |
\n|————-+—————————|
\n| ^100_ | Learned from AS 100 |
\n|————-+—————————|
\n| _100$ | Originated in AS 100 |
\n|————-+—————————|
\n| _100_ | Any instance of AS 100 |
\n|————-+—————————|
\n| ^[0-9]+$ | Directly connected ASes |
\n+————-+—————————+
\n<\/p><\/blockquote>\n

ip as-path access-list 1 deny ^10_ deny all the networks that have been learned from AS 10
\nip as-path access-list 1 permit 195.88.228.96 mask 255.255.255.255
\nip as-path access-list 1 permit 195.88.229.96 mask 255.255.255.255
\nip as-path access-list 1 deny _65156$ deny all the networks that have originated from AS 65156
\nip as-path access-list 1 deny .* deny all other routes<\/p>\n

** ip as-path access-list 10 permit ^$ permit locally originated routes **<\/p>\n

ip as-path access-list 2 deny _39173$ deny all the networks that have originated from AS 39173
\nip as-path access-list 2 permit .* permit all other routes
\n!
\nip as-path access-list 1 deny _10$ deny all the networks that have originated from AS 10
\nip as-path access-list 1 permit .* permit all other routes<\/p>\n

** ip as-path access-list 10 permit ^$ permit locally originated routes **<\/p>\n

ip as-path access-list 2 deny _39173$ deny all the networks that have originated from AS 39173
\nip as-path access-list 2 permit .* permit all other routes<\/p>\n","protected":false},"excerpt":{"rendered":"

+————-+—————————+ | Expression | Meaning | |————-+—————————| | .* | Anything | |————-+—————————| | ^$ | Locally originated routes | |————-+—————————| | ^100_ | Learned from AS 100 | |————-+—————————| | _100$ | Originated in AS 100 | |————-+—————————| | _100_ | Any instance of AS 100 | |————-+—————————| | ^[0-9]+$ | Directly connected ASes […]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[83],"tags":[78],"_links":{"self":[{"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2139"}],"collection":[{"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2139"}],"version-history":[{"count":2,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2139\/revisions"}],"predecessor-version":[{"id":2141,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=\/wp\/v2\/posts\/2139\/revisions\/2141"}],"wp:attachment":[{"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2139"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2139"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/darenmatthews.com\/blog\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2139"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}