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Forum Replies

  1. is this how most companies block access, i think we use something called websense?


    also with facbeook having so many webservers in a farm for redundancy would you in real world scendario block by ip, or hostname?



  2. Hi Ruby,

    The time based access-list is basically the “poor man’s” solution to block access on routers. You can use access-lists only to filter on L3/L4 information (IP addresses, protocols and port numbers) so you can’t filter based on hostnames.

    One way to get around this is to block all prefixes that belong to a certain AS. For example, facebook uses AS 32934. We can find their prefixes with whois:

    $ whois -h whois.radb.net -- '-i origin AS32934' | grep 'route:'
    route: 66.
    ... Continue reading in our forum

  3. Dear Rene,

    Thanks for your article…

    What will be the command periodic if we want to block traffic from Sunday to Thrusday ?


  4. Hi Zaman,

    You can use some of the default periodic options:

    Router(config-time-range)#periodic ?
      Friday     Friday
      Monday     Monday
      Saturday   Saturday
      Sunday     Sunday
      Thursday   Thursday
      Tuesday    Tuesday
      Wednesday  Wednesday
      daily      Every day of the week
      weekdays   Monday thru Friday
      weekend    Saturday and Sunday

    Including “weekend”.


  5. Hi Rene,
    In our client network,
    The Cisco Layer 2 Switch 2960G port 15 which is connected to the L2VPN MPLS-TP network and each month or time not remembering , the port is getting down and they are changing the port to other 16 Which was also configured for the same service. Once contractor was done this but client want to know if there is any time based port security is enable or no, Kindly share your advise.

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