I took a stab at moving wikisource-dev but ran into a problem with my migration regimen, so I've reverted for now. Everything should be as it was but this issue is still pending.

OK -- now I've migrated wikisource-dev. Can you please verify that it looks correct to you? Once I get confirmation I'll migrate wikisource-tools as well.

It looks correct to me. Thanks a lot.

For wikisource-tools the best test to see if the migration is a success is to test if http://wsexport.wmflabs.org/tool/stat.php returns a non empty statistic table.

Ok, done! Please confirm that everything looks right, then close this bug and move wikisource-tools to the 'finished' section here: https://wikitech.wikimedia.org/wiki/Labs_Eqiad_Migration_Progress

Thanks a lot!

But I see that the "puppet" status of wsexport.eqiad.wmflabs instance is "failed" and I don't manage to get in using ssh: I'm able to login into bastion-eqiad.wmflabs.org without any problems and then "ssh wsexport.eqiad.wmflabs" returns "Permission denied (publickey).".

This should be fixed now... is that instance treating you OK?

No, I have ever this error when I try to login into wsexport.eqiad.wmflabs from bastion-eqiad. Here is what I run:
$ ssh tpt@bastion-eqiad.wmflabs.org
and then
tpt@bastion1:~$ ssh wsexport.eqiad.wmflabs
that returns:
Permission denied (publickey).

Do you mean

$ ssh -A tpt@bastion-eqiad.wmflabs.org

? Because the way you wrote it it would never work :) Access works fine for me...

using the "-A" option doesn't change anything to the problem :-(. I've delete and then re-added my public key but it doesn't change anything too.

The issue was on my side