Set UDP buffer in HPUX 11.x

[Claudio Lombardo]

Is there a command (like ndd) to set a UDP buffer size?

Thank you.

Claudio

[Sandip Ghosh]

You can try with nettune. For options look at man nettune.

Sandip

[Ron Kinner]

ndd -h does not show anything. (nettune is not used after 10.3) I know there is a patch which effects one of the buffers. PHSS_17810 There may be others.

Ron

[Claudio Lombardo]

I'm sorry. This is not the right solution... I get a buffer overrun while getting a lot of UDP messages from a Router (I'm using IUM with a Netflow Encapsulator).
I think it must be a method to increase the UDP buffer, like TCP.

Thanks,
Claudio

[Clemens van Everdingen]

Hi,

I once had an issue with udp buffer overflow's.

I got an answer like this:

Unfortunately there is nothing you can do from the admin perspective it can only be done during the binding of the socket.

Meaning: the programmer should change this value.

C.

[sven verhaegen]

Hi

I have some bad news for you , unfortunately there is no way of changing this "on-the-fly" at the moment , not even in NDD , there has been a service enhancement request opened at HP for a while now describing the need for such a feature in ndd but it hasn't been implemented yet (probably is previewed for HP-UX v.12), there is only one way of altering it altogether left to you and as explained before it is altering the application that allocates the buffers by using the setsockopt() systemcall . It unfortunately cannot be done on the command line ...

[Ron Kinner]

Since a bigger buffer does not seem to be available perhaps you should look at trying to empty the buffer faster?

Unless this UDP traffic is very bursty a bigger buffer is not going to help much. Try adding memory, dropping unneeded processes or moving them to a different machine, adding another processor.

Alternatively can you throttle the traffic down at the source?

Ron