8:15p
   I submitted a fix for the segfaults
   at [1]https://github.com/filecoin-project/lotus/pull/6787 .
   I don't understand the underlying cause well.  I'm guessing it's
   because some of the dealids were lost, maybe they didn't go through
   while the node was offline, dunno.
   One of my deals remains and it has completed.  Theoretically the data
   is online!  8:17p
   8:21
   when I search for my uploaded file, lotus hangs.  It could be from my
   corrupt repository.
   8:22
   while I was typing the above, lotus found the uploaded file and said it
   could retrieve it
   8:23
   I deleted the data from lotus's local repository and will try to
   retrieve it from the miner storing it.
   9:32
   It retrieved fine my hello-world.txt, although I am only now actually
   paying attention to where it goes and looking at it.  I tried for some
   time to figure out how to request it from specific miners using the cli
   tools: this seemed hard to figure out without using
   [2]https://filecoin.tools to lookup the form of the payload cid
   involved =/
   The find function and retrieve function appear to possibly use the same
   offer object, so it is  easy to do programmatically by attending to
   whatever it is of importance that is in the offer object.
   It takes about 2 minutes to retrieve my helloworld file.  I think it is
   mostly because it is pinging nonresponsive nodes to see if they can
   send it.  A quick workaround would be to stop as soon as a reasonable
   node is found.  But we do want a way to probe nodes for whether they
   still will send a file.
   I'll check the actual download, and then see if I can get it with a
   fresh .lotus dir, I guess.

References

   1. https://github.com/filecoin-project/lotus/pull/6787
   2. https://filecoin.tools/