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  • SSH unavailable after disconnect

    From mh@1:103/705 to All on Mon Sep 7 15:35:41 2020
    Hey everyone, new Synchronet sysop here. This must not be a unique problem but I can't seem to find an answer anywhere. After a SSH session is disconnected by anything other than a clean logout, new SSH connections are rejected for upwards of 5-10 minutes, as if it's waiting for some kind of timeout. After a while, it goes back to normal and starts accepting connections again and everything is fine. Has anyone experienced this and might have some suggestions for how to fix or mitigate it?

    Thanks
    -mh

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    þ Synchronet þ Sent from No Agenda BBS
    * Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)
  • From Digital Man@1:103/705 to mh on Mon Sep 7 22:22:19 2020
    Re: SSH unavailable after disconnect
    By: mh to All on Mon Sep 07 2020 03:35 pm

    Hey everyone, new Synchronet sysop here. This must not be a unique problem but I can't seem to find an answer anywhere. After a SSH session is disconnected by anything other than a clean logout, new SSH connections are rejected for upwards of 5-10 minutes, as if it's waiting for some kind of timeout. After a while, it goes back to normal and starts accepting connections again and everything is fine. Has anyone experienced this and might have some suggestions for how to fix or mitigate it?

    What does the server report when its rejecting these SSH connections? No, I've never seen this myself.

    digital man

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    * Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)
  • From mh@1:103/705 to Digital Man on Tue Sep 8 07:02:08 2020
    Re: SSH unavailable after disconnect
    By: Digital Man to mh on Mon Sep 07 2020 22:22:19

    What does the server report when its rejecting these SSH connections? No, I've never seen this myself.

    I've just done some further testing, and the problem does not appear to be with the BBS itself. Local connections work fine, but remote connections are rejected with: "ssh_exchange_identification: Connection closed by remote host".

    So I guess that makes my question slightly off topic. It must be an issue in the firewall or server configuration somewhere. Any suggestions where to look first?

    -mh

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    þ Synchronet þ Sent from No Agenda BBS
    * Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)
  • From mh@1:103/705 to Digital Man on Tue Sep 8 09:28:37 2020
    Re: SSH unavailable after disconnect
    By: mh to Digital Man on Tue Sep 08 2020 07:02:08

    I've just done some further testing, and the problem does not appear to
    be with the BBS itself.

    I was wrong, it is a problem with the BBS and I've found it. The issue was the 'new' user appearing in name.can. A failed new user login triggers the TempBan, locking all new user creation for 10 minutes. I have the new user password set for the moment, and there was some confusion with users about needing to enter a new user password twice when connecting over SSH, thus frequently triggering the problem.

    -mh

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    þ Synchronet þ Sent from No Agenda BBS
    * Origin: Vertrauen - [vert/cvs/bbs].synchro.net (1:103/705)