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Solution for com.jcraft.jsch.JSchException: reject HostKey problem on Ubuntu

Just a random investigation with a workaround. So trying to connect to SFTP server using jsch library, but getting a nasty com.jcraft.jsch.JSchException: reject HostKey exception. This host is already present in ~/.ssh/known_hosts file, so it should not be problem, but it is. It turns out this problem happens if SFTP server is running on Ubuntu and strictHostKey is set to true, but it doesn't happen on Linux Fedora. I suppose this is because host entries in the known_hosts file on Ubuntu are encrypted in a different way than in known_hosts on Fedora, so it cannot be recognized or decrypted by JSch library. Now all you need to do is manually add host entries to the file. Basically you just get the public key for the host where SFTP server is running using this command: 
ssh-keyscan -t rsa sftp_server_ip_address_or_hostname
Then copy-paste the output to your local ~/.ssh/known_hosts file. That's all, it should work now. If it doesn't, try to empty known_hosts file completely, than insert the public key.
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