no matching key exchange method found. Their offer: diffie-hellman-group1-sha1
How to solve key Exchange Method Mismatch in SSH: diffie-hellman-group1-sha1 Offered?
Overview: This article helps to resolve the error "no matching key exchange method found. Their offer: diffie-hellman-group1-sha1" while logging into EXOS network switch from Ezeelogin.
Unable to SSH into the EXOS network switch from the gateway server. The SSH client displays the error message: "Unable to negotiate with IP on port 22: no matching key exchange method found. Their offer: diffie-hellman-group1-sha1."
The above error occurs because OpenSSH and other SSH libraries have removed default support for diffie-hellman-group1-sha1.
Step 1: Try to upgrade your switch firmware and see if that solves your problem.