If you don't like to edit /etc/ssh_config as root, put the line into ~/.ssh/config instead.

Excellent hint.

But for some users, who may not be able to comfortably edit the '/etc/ssh_config', here's a pretty nifty workaround.

If you're using your .basrc file to set config settings for your term, you can simply create an alias:

alias ssh='ssh -4'
-->the -4 forces ssh to only try to connect using IPv4

Another handy technique, I also use is the '-v' switch whenever I'm connecting to a remote host.
-->the -v turns on verbose mode, and print any ssh client/server msgs to the screen, so you know exactly what's up. Perfect for debugging trouble-some connections.

That alias now becomes: alias ssh='ssh -4 -v', so whenever you invoke the ssh command from the cli, 'ssh -4 -v' is actually sent, and all you have to do is specify your other connection options.

I use a creative mix: /etc/ssh_config, ~/.ssh/config and my .bashrc, to get it just right. Plus I find it keeps things in the correct order, as ssh actually reads prefs in that order, anyway.

Hope this can help someone.

---
/the Perverted Monk
"my rant is my giant exhale... my exasperation at this approximation
of civilization that causes mad denigration in multiple nations"

Small Clarification
---------------------

SSH prefs are read in this order;
CL options--> user options --> system options.

---
/the Perverted Monk
"my rant is my giant exhale... my exasperation at this approximation
of civilization that causes mad denigration in multiple nations"