On 12/5/21, Richard W.M. Jones wrote:
openssh 8.8p1 (just released in Rawhide) cannot connect to older
servers. The error is:
Unable to negotiate with [server] port 22: no matching host key type found. Their
offer: ssh-rsa,ssh-dss
It seems like the cut-off point is RHEL <= 6 broken, RHEL >= 7 is OK.
I eventually found a workaround/solution to this deep in an Arch
thread:
https://bbs.archlinux.org/viewtopic.php?pid=2006291#p2006291
or the equivalent on the command line:
ssh -o HostKeyAlgorithms=+ssh-rsa -o PubkeyAcceptedAlgorithms=+ssh-rsa rhel6
Both config options seem to be necessary.
Thank you for concisely documenting the problem and workaround.