use ndd to tune udp parameter

[tang zhibo]

Hi all,
I use "ndd -h sup", and see parameter "socket_udp_rcvbuf_default", but I can find any network device related with this parameter, how can I set its value?
Thanks!
bo

[steven Burgess_2]

Hi

use nnd -get

[Stefan Farrelly]

Or you can add them into the system startup file for ndd, /etc/rc.config.d/nddconf
Then everytime you reboot they will take effect. If you do it on the command line they are lost when you next reboot.
For example we have some in ours for TCP timeouts;

TRANSPORT_NAME[0]=tcp
NDD_NAME[0]=tcp_ip_abort_interval
NDD_VALUE[0]=30000

TRANSPORT_NAME[1]=tcp
NDD_NAME[1]=tcp_ip_abort_cinterval
NDD_VALUE[1]=15000

TRANSPORT_NAME[2]=tcp
NDD_NAME[2]=tcp_fin_wait_2_timeout
NDD_VALUE[2]=15000

[sven verhaegen]

commands are

ndd -get /dev/udp socket_udp_rcvbuf_default

to get actual value

ndd -set /dev/udp socket_udp_rcvbuf_default

to change the value

if it is a UDP setting you need the /dev/udp , I had a look at a 11.0 system but could not find the parameter you are talking about is this a 11.0x or 11.i machine?

[U.SivaKumar_2]

hi,
While setting udp parameters

#ndd -set /dev/udp "any_udp_parameters"

Checking the udp paramter

#ndd -get /dev/udp "any_udp_parameters"


regards,
U.SivaKumar

[tang zhibo]

hi steven,
The ndd command is used like "
ndd -get network-device parameter value
"
Devices like /dev/tcp, /dev/udp can be found, but parameter socket_udp_rcvbuf_default is belonged to device SOCKET, but I can't find it in /dev directory.
Thanks
bo

[tang zhibo]

hi sven,
This is a 11.22 box, I want to tune the udp packet receive ability for it. Another alternative is to use setsockopt in the program.
thanks, all of you.
bo

[Steven Sim Kok Leong]

Hi,

I am using HP-UX 11.20 and I don't see this parameter, so it must be specific to HP-UX 11.22.

What is displayed when you type:

# ndd -h socket_udp_rcvbuf_default

Usually, this will provide you with more details on the parameter.

For parameters belonging to the /dev/udp category, they will start with udp_ etc. However, this is the first time I see a network parameter beginning with socket_. It usually begins with ip_, arp_, tcp_, udp_, rawip_ or icmp_.

Both ndd -h sup and ndd -h unsup on HP-UX 11.20 shows you the category a network parameter belongs to.

Hope this helps. Regards.

Steven Sim Kok Leong

[Brian Hackley · Accepted solution]

Hi,
I get alot of oddball tuning questions here in the HP Response Center, so your question got me very interested in finding an answer. Here is what I found. Use ndd -get/set sockets socket_udp_rcvbuf_default

If nothing is displayed, it might be because of a bug in the ARPA Transport on your 11.2X box. I found the bug documented in the 11.11 ARPA Transport patch PHNE_25644:
, SR:8606223770 CR:JAGad92866 )
"ndd -get" does not display anything for socket
tunable parameters.

Since the bug was just fixed in early May, I would suspect that it is an outstanding issue for 11.2X and that you should work the issue with your HP Support contact.

As an aside, use ndd -h sockets to get list of sockets params, or ndd -h supported |more for the complete list of supported ndd params.

Hope this helps,

-> Brian Hackley

[tang zhibo]

hi,
"ndd -get/set sockets socket_udp_rcvbuf_default" works.
thanks.
bo