MiamiCuse wrote:
....

However it makes me wonder, the fact that the pipe is sliding, I am
thinking it should have flashings and sealant against the pipe right?
does it mean the roof seal is broken? I have not gotten up on the
roof yet, I am a bit paranoid to climb up there. What is the proper
way to fix this? The second question is, since the pipe is sliding, I
assume if I were to loosen up the no hub coupling I should be able to
pull out the entire contraption on the roof? if so should I just glue
in a piece of PVC all the way instead of using a short 8" cast iron
pipe?

A) yes and maybe (depends on what is there)

B) can't tell if it needs fixing even, from here

C) This is actually third (or fourth if count first compound query as
two instead of only one), but -- maybe but can't tell what's there from here

D) Could do that; whether it's better or simple depends on the
aforementioned what's there now.

IIRC you've got tile roof? If so, could be a pita.

If the present has a rubber boot that's still in good shape that it
moved a little may have had no significant impact. OTOH, if it is a
hooded exit, pushing it back up may have lifted the whole thing away
from the roof--probably not, but again w/o no info, no way to tell...

_Somebody'll_ (whether it's you or another) have to get up there and see
whatcha' gots and what it needs, if anything...or, of course, you could
simply wait 'til it rains next time and see if you have a leak and
assume if you don't it's ok...

If you do, you'll know for sure it isn't altho still won't help w/ the
specifics of what you need, of course...

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