[CentOS] Semi-OT: very weird vi behaviour

This is weird. As in, *deeply* weird.

I ssh as root from one box to another (there are keys involved), and I go
to vi a file, such as
# line 1 #
# line 2 #
# line 3
# line 4

And what I see in vi is
# line 3
# line 4

BUT, if I scroll the cursor over each line with the arrow key... I see all
four lines. I've also looked at another file, and same thing. Just checked
it out on the server I ssh'd in from, and no problem.  And now, I just
ssh'd in from another windows, same way... and the weirdness isn't there.

Anyone have any clues as to what's going on with that one session?

         mark

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