SSH cipher RC4 removed from OS X 10.11 El Capitan

The fast (but broken and thus insecure) cipher RC4 has been removed from OS X with El Capitan. The ssh server does not allow log in with the -c arcfour option anymore. Instead you will receive an error message like:

RC4 self test

$ ssh -c arcfour localhost
ssh_dispatch_run_fatal: Connection to ::1: no matching cipher found

The ssh client portion seems to still support RC4 because I seem t be able to still connect to Linux servers that have support for RC4 still enabled but the SSH server portion has RC4 disabled.

I generally like this move because and I think it took apple way to long to obsolete RC4 support. 01/20/2016

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