Hi everyone. I wanted to share my latest experience with you in case anyone else runs into this.
After applying the 6.0U2 update to a standalone ESXi host I was unable to SSH to the host anymore from PuTTY on my Windows workstation. I know that the 6.0U2 update had some pretty big changes to the SSH daemon so I was pretty sure it was related to that. I searched Google and the VMware knowledge base without much luck. I ran across these articles:
But those articles don't apply to 6.x. But they pointed me in a direction to check in the /var/log/auth.log file for any errors. I did indeed find the following errors:
016-06-20T21:52:38Z sshd[40905]: error: Hm, kex protocol error: type 30 seq 1
I did a quick Google search and ran across this article: https://blog.nytsoi.net/2015/07/13/putty-kex-error. The problem (as I understand it) is that the key exchange method "Diffie-Hellman group exchange" is not supported with the version of OpenSSH that is used on the ESXi host. The work-around was fairly easy. The blog article referenced above says:
In PuTTY, go to “Connection → SSH → Kex”. There, select “Diffie-Hellman group exchange” and move it to the bottom of the list, so it is not used.
As soon as I did that, I was able to use PuTTY to connect to the standalone ESXi host.
Hope anyone else finds this information useful. It definitely had me scratching my head for a while.
Hello warnesjSHR,
Great post, i had the same problem but with ESXI 6.0, the workaround worked very fine to me.
Thanks a lot,
Luis Fuentes.
Thanks for posting,
great, it works fine with ESXi 6.5 to
Thanks for the post.
It is helpful for ESXi 6.7 as well.
Regards,
Reynaldo
Thank you for taking the time to share this. This saved me hours more of frustration. It worked for me on esxi 6.0.
Cheers ... Ron