Antwort: NRPE enhanced for larger data

Andreas Ericsson ae at op5.se
Tue Aug 5 12:54:12 CEST 2008


Ton Voon wrote:
> On 5 Aug 2008, at 08:59, Sascha.Runschke at gfkl.com wrote:
> 
>> nagios-devel-bounces at lists.sourceforge.net schrieb am 05.08.2008  
>> 01:32:36:
>>
>>> We've made a change to NRPE so that it can accept more data while
>>> still being backwards compatible with existing NRPE servers. Can  
>> this
>>> be applied to the core code? More details at http://altinity.blogs.
>>> com/dotorg/2008/08/enhancing-nrpe.html
>> I've read the article, but I'm not entirely sure how you handle those
>> packets. Does it mean your patch raises the default size of the
>> packets to 16k? Right now nrpe allocates its maximum outputbuffer
>> and fills it with null bytes if the output is less - which is already
>> a pain in my opinion.
>> If you'd raise the output buffer from 600 bytes (or whatever it was,
>> can't recall it right now) to like 16k, that would spike up network
>> traffic tremendously and I'm quite sure that would break quite a few
>> setups. We already have someone in the german community who complains
>> about the useless ~400 bytes sent over the network ;)
> 
> No, the packets are still 1K in size. You're right that the article  
> does not make this clear - I've updated it to hopefully be a bit  
> explanatory.
> 
> The patch makes a change so that if a response comes back saying there  
> is more data to come, then check_nrpe reads subsequent packets. So to  
> get 16K worth of data, it reads 16 x 1K packets.
> 
> I agree the empty packets are a waste. You can't change the packet  
> size without a change in the protocol since both the client and server  
> expect packets at a fixed size. That's a larger (and non-compatible)  
> change for the future.
> 

... and it still won't do anything for the encrypted protocols, since
they require fixed-size blocks to work in any sane setting too.

-- 
Andreas Ericsson                   andreas.ericsson at op5.se
OP5 AB                             www.op5.se
Tel: +46 8-230225                  Fax: +46 8-230231

-------------------------------------------------------------------------
This SF.Net email is sponsored by the Moblin Your Move Developer's challenge
Build the coolest Linux based applications with Moblin SDK & win great prizes
Grand prize is a trip for two to an Open Source event anywhere in the world
http://moblin-contest.org/redirect.php?banner_id=100&url=/




More information about the Developers mailing list