On Sun, August 1, 2010 21:41, Vernon Everett wrote:
I will have a chat. There is a very cordial relationship, but politics, as always, makes it.....interesting. I am not going to go into any further detail in an open forum. :-)
Before I have my chat though, I need to be armed with more info. Using little words, and sock-puppets (if required), can you explain exactly what the ares doo-hicky actually does? What happens differently when we run Xymon with and without the --no-ares?
You may get better answers from folks familiar with the actual code, but my take is that with --no-ares Xymon uses the threaded, synchronous system resolver library, which would tend to choke down the rate of hits against whatever DNS servers are used (and slow down the loop through bb-hosts), compared to ares.
With a caching local DNS server, you'd be optimizing the use of the hits against the "real" DNS servers, not repeating a lookup until the TTL has run on the last real lookup of the hostname. This would tend to mitigate the hammering from using the ares resolver functions.
Again, that's my take. Wait and see if anyone says I'm horribly wrong before taking that into a meeting.