Comment 7 for bug 1405232

Couldn't the upstream fix be to time out the DNS resolution? If you don't have an answer in X seconds/milliseconds, never mind and carry on. It's just ping, after all, and it's a good idea to make low level diagnosis independent of higher level functionality, as noted in the Debian bug report.

Caching hostnames in ping is a possible strategy, but that's what the local resolver is for. IMHO, that's not something ping should bother doing.