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  • blocking IP addresses

    From Shadow Man@1:103/705 to all on Tue Oct 13 12:57:41 2026
    What is the best way to block either a ip or ip range from my system (telnet specifically). I have altered the ip.can file with the ip, and it seems I'm being continuously hit over and over on Port 23.

    Thanks!

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  • From Nightfox@1:103/705 to Shadow Man on Tue Oct 13 17:36:14 2026
    Re: blocking IP addresses
    By: Shadow Man to all on Tue Oct 13 2026 12:57 pm

    What is the best way to block either a ip or ip range from my system (telnet specifically). I have altered the ip.can file with the ip, and it seems I'm being continuously hit over and over on Port 23.

    Adding to ip.can is the correct way, as far as I know. But even if you add an IP address there, you'll likely still get attacked from other IP addresses. It supports wildcards though, so you could add something like 180.* (I believe) to block a whole range.

    Also, perhaps some of the server settings such as MaxConConnFilterThreshold & others could help you:

    https://wiki.synchro.net/config:sbbs.ini#maxconconnfilterthreshold

    Nightfox

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  • From Digital Man@1:103/705 to Shadow Man on Tue Oct 13 18:13:46 2026
    Re: blocking IP addresses
    By: Shadow Man to all on Tue Oct 13 2026 12:57 pm

    What is the best way to block either a ip or ip range from my system (telnet specifically). I have altered the ip.can file with the ip, and it seems I'm being continuously hit over and over on Port 23.

    If you added an IP address to your text/ip.can file, it should be immediately disconnected by all Synchronet servers/services upon connection:
    https://wiki.synchro.net/howto:block-hackers
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    digital man (rob)

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  • From poindexter FORTRAN@1:103/705 to Shadow Man on Wed Oct 14 07:39:03 2026
    Shadow Man wrote to all <=-

    What is the best way to block either a ip or ip range from my system (telnet specifically). I have altered the ip.can file with the ip, and
    it seems I'm being continuously hit over and over on Port 23.

    Are you actually getting hit, or are you getting notifications that the
    attempt is blocked? There's a way to block attempts without logging.

    look at ip-silent.can.



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  • From nelgin@1:103/705 to Shadow Man on Wed Oct 14 11:54:47 2026
    Re: blocking IP addresses
    By: Shadow Man to all on Tue Oct 13 2026 12:57:41

    What is the best way to block either a ip or ip range from my system (telnet specifically). I have altered the ip.can file with the ip, and it seems I'm being continuously hit over and over on Port 23.

    iptables

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  • From Accession@1:103/705 to Shadow Man on Wed Oct 14 17:43:40 2026
    Hey Shadow!

    On Tue, Oct 13 2026 12:57:40 -0500, you wrote:

    What is the best way to block either a ip or ip range from my system (telnet specifically). I have altered the ip.can file with the ip, and it seems I'm being continuously hit over and over on Port 23.

    You can start adding them to ip-silent.can instead. Then, while they'll still try and fail, at least you won't see that they're continuously hitting you over and over (it's not logged). ;)

    Regards,
    Accession

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  • From Charles Claypoole@1:103/705 to poindexter FORTRAN on Wed Oct 14 20:18:07 2026
    there was a ip that kept connecting to my port 23, then disconnecting, and rinse in repeat for hours. it eventually stopped but I tried the ip.can and the ip.silent entry.

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