[Xymon] c-ares

[John Thurston]

On 11/1/2013 10:11 AM, John Thurston wrote:
> On 11/1/2013 9:35 AM, Mark Felder wrote:
>> Is there any hope of getting xymon to compile against the system
>> provided c-ares, or is xymon always going to bundle it? Just seems like
>> it would be more efficient to use the system-provided c-ares if it's
>> there...
>
> It's funny you bring this up right now. I am currently struggling with
> my pre-production xymon instance. The only way I seem able to get it to
> behave is to start xymonnet with --no-ares. When using c-ares, I
> routinely get hundreds of test failures due to inability to resolve names.

I've been working on this today and have found the undocumented option 
to xymonnet "--maxdnsqueue". With this, I can limit the number of 
queries xymonnet sends to name servers in each batch. When I set it to 
=10, I get solid results. When I set it to =25 (or higher), I get 
hundreds of name resolution failures.

When I use --no-ares, it also works fine.

My original question remains, "Why is c-ares the default rather than the 
system resolver?" But more important is the practical question . . .

Which way should I go:
   --no-ares and use the name server caching daemon (nscd) in Solaris?
   --maxdnsqueue and hope it becomes documented and not deleted?


-- 
    Do things because you should, not just because you can.

John Thurston    907-465-8591
John.Thurston at alaska.gov
Enterprise Technology Services
Department of Administration
State of Alaska