Iceland, the lowest-ranked team in the play-offs, must beat Croatia to reach their first ever major tournament, while Greece meet Romania.
The two-legged ties will be played on 15 November and 19 November.
The eight nations all finished second in the qualifying groups, with 1998 World Cup winners France runners-up to current holders Spain in Group I.
Ukraine were beaten to automatic qualification by Group H rivals England.
Portugal, Greece, Croatia and Ukraine were the four seeded teams in the draw which took place on Monday.
The four teams that qualify will complete a total of 13 European nations at the tournament in Brazil.
(source)
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Tough draw for Portugal and France. Hopefully Paulo Bento will get out of his own way long enough for Portugal to make it through.