Intermittent incorrect DNS resolution?

Erik Levinson erik.levinson at
Wed Jan 16 22:26:43 UTC 2013

Good point.

While I haven't checked the distribution of source IPs yet, I briefly 
grepped for the User-Agent headers in the tcpdump output, and there's a 
higher than expected bot presence, particularly Baidu.

That said, there are also "normal" UAs (whatever that means, with every 
device/software pretending to be something else these days).

On 16/01/13 05:20 PM, RijilV wrote:
> Also client programs don't always honor TTLs either.  For example, JAVA
> defaults to ignoring TTLs and holding IPs forever.
> *networkaddress.cache.ttl (default: -1)*
> Indicates the caching policy for successful name lookups from the name
> service. The value is specified as as integer to indicate the number of
> seconds to cache the successful lookup. A value of -1 indicates "cache
> forever".
> Depending on who your clients are, your milage may vary.
> .r'

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