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Ventura compatibility (15 posts)

  • Started 1 month ago by dcp10
  • Latest reply 1 month ago from Idid
  • dcp10 Member

    I used Fetch successfully immediately before upgrading to Ventura. Now I get an error message every time I try to connect to our web server:

    "SFTP connection to <a.b.c.d> could not be opened because the connection to the SFTP server could not be established or was lost."

    "Try again, or contact the server administrator to verify that you have the correct hostname, username, password, and authentication method, and that the server is running.
    Server responded: “Unable to negotiate with <a.b.c.d> port 2020: no matching host key type found. Their offer: ssh-rsa,ssh-dss

    Nothing has changed in our network configuration - and I am able to use "Transmit" from Panic Software just fine. Is there something that needs to be set in the new "System Settings" in order to get Fetch 5.8.2 to work on Ventura?

    Posted 1 month ago #

  • Jim Matthews Administrator

    Hi,

    The problem is that by default Ventura does not use the host key algorithm used by your SFTP server (Apple made this change to improve security). You may want to ask your SFTP server administrator to upgrade to newer host key algorithms. Otherwise you can work around this change by doing the following:

    1) Choose Utilities from the Go menu in the Finder
    2) Open Terminal
    3) Enter the following (replacing HOSTNAME with your server's hostname):

    echo -e "\nHost HOSTNAME\nHostkeyAlgorithms +ssh-dss\n" >> ~/.ssh/config

    and press Return.

    Please let me know if that does not work.

    Thanks,

    Jim Matthews
    Fetch Softworks

    Posted 1 month ago #

  • dcp10 Member

    Thanks, Jim - but I'd rather not tinker with any system settings, if at all possible.

    I'm curious that "Transmit" is able to access the exact same files without any errors. Is there any way to update Fetch so that it behaves similarly?

    Posted 1 month ago #

  • Jim Matthews Administrator

    Hi,

    Transmit is not enforcing the same security standards as Ventura's default SSH configuration. Fetch uses Ventura's SSH implementation, so you can have it behave similarly by configuring SSH to allow the sort of hostkey that your SFTP server requires. Note that this configuration change only affects connections that you make to that SFTP server, it does not affect the system in general.

    Thanks,

    Jim Matthews
    Fetch Softworks

    Posted 1 month ago #

  • dcp10 Member

    Thanks for the clarification, Jim.

    I tried your command, entering a string of the form:

    echo -e "\nHost <hostname>\nHostkeyAlgorithms +ssh-dss\n" >> ~/.ssh/config

    where instead of <hostname> I entered the numeric IP address, e.g., 1.2.3.4.

    I then quit and restarted Fetch, but am getting the same problem. Maybe I need to restart? Or is there something else required?

    Posted 1 month ago #

  • dcp10 Member

    The error message now is:-

    Server responded: “/Users/david/.ssh/config: line 1: Bad configuration option: -e
    /Users/david/.ssh/config: terminating, 1 bad configuration options

    Posted 1 month ago #

  • Jim Matthews Administrator

    Hi,

    Does the error message still say

    Server responded: “Unable to negotiate with <a.b.c.d> port 2020: no matching host key type found. Their offer: ssh-rsa,ssh-dss

    ?

    Thanks,

    Jim Matthews
    Fetch Softworks

    Posted 1 month ago #

  • dcp10 Member

    No - see my message above.

    Posted 1 month ago #

  • dcp10 Member

    No - see my message above.

    Posted 1 month ago #

  • dcp10 Member

    I've tried manually editing the .ssh/config file, so that it now reads:-

    Host webserver
    HostName 1.2.3.4
    HostKeyAlgorithms +ssh-dss

    Having done this, the error message is now back to the original one, i.e.,

    Try again, or contact the server administrator to verify that you have the correct hostname, username, password, and authentication method, and that the server is running.
    Server responded: “Unable to negotiate with <a.b.c.d> port 2020: no matching host key type found. Their offer: ssh-rsa,ssh-dss

    Posted 1 month ago #

  • Jim Matthews Administrator

    Hi,

    It looks like you're connecting to port 2020. Could you edit your config file to look like this:

    Host webserver
    HostName 1.2.3.4
    Port 2020
    HostKeyAlgorithms +ssh-dss

    and see if that makes a difference?

    Thanks,

    Jim Matthews
    Fetch Softworks

    Posted 1 month ago #

  • dcp10 Member

    Sorry, it didn't make any difference at all - exactly the same error.

    I should note that the .ssh folder also contains a file entitled "known_hosts". This includes the IP address we're trying to access, with a line like:

    [1.2.3.4]:2020 ssh-rsa <gobbledygook>

    I have no idea who or what generated this - there seem to be other addresses in there too.

    Posted 1 month ago #

  • Jim Matthews Administrator

    Thanks for trying that. Could you try changing "+ssh-dss" to "+ssh-rsa"?

    Posted 1 month ago #

  • dcp10 Member

    I tried changing the last line of the "config" file, to:

    HostKeyAlgorithms +ssh-rsa

    Sadly, this made no difference; same error as before.

    Posted 1 month ago #

  • Jim Matthews Administrator

    Hmm. Could you contact me at https://fetchsoftworks.com/fetch/feedback ? I'd like to get some more information.

    Thanks,

    Jim Matthews
    Fetch Softworks

    Posted 1 month ago #

  • Idid Member

    I had the same problem after Ventura update.
    Jim solution is right "Could you try changing "+ssh-dss" to "+ssh-rsa"?"

    it is easy to identify because the site is answering "Their offer: ssh-rsa" instead "Their offer: ssh-rsa"
    thanks and best regards

    Posted 1 month ago #

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