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    Block domains on a Cisco ASA

    By default you can block domains with a Cisco ASA.
    It simply blocks the typed DNS domain names.
    Be aware that the IP (ex: can be accessed until you deny this in an access-list.

    regex domainlist1 “\.dating\.dk”
    regex domainlist2 “\.facebook\.dk”
    regex domainlist3 “\.facebook\.com”
    access-list inside_mpc extended permit tcp any any eq www
    access-list inside_mpc extended permit tcp any any eq 8080
    class-map type regex match-any DomainBlockList
    match regex domainlist1
    match regex domainlist2
    match regex domainlist3
    class-map type inspect http match-all BlockDomainsClass
    match request header host regex class DomainBlockList
    class-map inspection_default
    match default-inspection-traffic
    class-map httptraffic
    match access-list inside_mpc
    policy-map type inspect http http_inspection_policy
    protocol-violation action drop-connection <— XX
    match request method connect
    drop-connection log
    class BlockDomainsClass
    reset log
    policy-map inside-policy
    class httptraffic
    inspect http http_inspection_policy
    service-policy inside-policy interface inside

    Block all domains containing the word “facebook” ex: myfacebook.com

    regex domainlist1 “.*facebook.*”