Created attachment 439997 [details]
Strace of a failing whois
Customer has run into a problem with the same symptoms as BZ 415481. On an IPV4 only connection whois querys all fail.
[root@tux ~]# whois 18.104.22.168
[Unable to connect to remote host]
The fix was a broad package upgrade in the referenced bug. Bug also included an strace which I will reattach here.