/etc/nsswitch.conf.
This was because of two reasons:
- /etc/hosts lookup code damaged some of internal
state used by gethostbyname2().
- getaddrinfo() was not persistent enough against errors.
Sorry for the delay, and hope this fix all the following PRs
(I checked in my environment immitating those PRs and it worked for me)
PR: 7901, 7912, 7921