Specify key exchange protocol with lftp

Question

I have to download some (large) data from a distant server.

The remote IT people suggest using lftp sftp://[e-mail]:port.

However, when I type ls, I read:

`ls' at 0 [Unable to negotiate with XXX.XXX.XXX.XXX port PPP: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1]

It seems that they cannot change their key exchange method now (yes, I know, it is subject to attack, I warned them).

So I used:

sftp -P port -o KexAlgorithms=+diffie-hellman-group1-sha1 [e-mail]

I type get -a -r *, but I now have problem with symlinks, which are poorly handled by sftp (as far as I know).

What are my options now?

Answer 1

Both lftp and sftp use /usr/bin/ssh as the transport – they let the SSH client establish the connection (starting the SFTP responder instead of an interactive shell) and only speak the SFTP protocol over stdin/stdout. Many other programs such as GVFS, rsync, Git, Borg, etc. also work the same way.

You can use ~/.ssh/config to specify custom settings that apply to all programs which invoke 'ssh':

Host server.domain
    KexAlgorithms +diffie-hellman-group1-sha1