Created attachment 172196 [details] whois 163.172.135.172 whois goes in an infinite loop when executing 'whois 163.172.135.172'. Checking other IP's seems to go fine. This happens on head (11.0-ALPHA6), while 10.3-RELEASE is fine.
Created attachment 173085 [details] Patch for 210892 It looks like this is a side effect from a fix for a redirect bug. The fix was introduced in commit 3389187e4b646b62f4754a92855389d967de816f (in the github repo). The original problem was whois didn't follow certain redirects correctly, and wouldn't give accurate information (the U of M example). There was a possible loop with APNIC however. The response from APNIC for the IP in this bug report would match the ERX-NETBLOCK, be redirected to ARIN, which would then redirect back to APNIC. I've proposed a patch which fixes the problem. But I'm not too familiar with the intricacies of the whois system. The original author probably has much more insight as to whether this solution is acceptable.
(In reply to rday from comment #1) Looks fine, fixes the problem.
Appears to be fixed in #aec30d9b More robust handling of whois referrals from RIRs. An example problem case is 163.1.0.0 (University of Oxford) which is in an APNIC ERX address range. Previously we assumed that ARIN has the correct information for all ERX allocations, but in this case ARIN refers back to APNIC, rather than referring to RIPE. This caused whois to loop. Whois will no longer loop back and forth forever between two RIRs that don't have an answer, but instead try the other RIRs in turn. ...
Reported fixed by r308762 / https://reviews.freebsd.org/rS308762