nddconf file

[Nikee Reddy]

Hello,

Could some one please explain to me the purpose of the nddconf file which is under /etc/rc.config.d ?

Here are the entries in the nddconf file in our system:

------------------------------
TRANSPORT_NAME[0]=ip
NDD_NAME[0]=ip_send_source_quench
NDD_VALUE[0]=0
ndd -set /dev/ip ip_send_source_quench 0
------------------------------

When I looked in the /etc/rc.log file I found an error related to this file.
But regarless of this error the system is up and running with out any problems. Before I comment out the above lines from nddconf file I just want to make sure your opinion on this?

Here are the error details from the /etc/rc.log file:

------------------------------
Configure LAN interfaces
Output from "/sbin/rc2.d/S340net start":
----------------------------
Invalid entries in nddconf
------------------------------

I really appreciate your response.

Thanks.

Best regards,
Nikee

[Con O'Kelly · Accepted solution]

The nddconf file automatically sets any network tunable parameters when the system is booted.

My guess is that you do not need the ndd -set /dev/ip ip_send_source_quench 0 line in this file.
This is automatically done by the startup scripts when you set above 3 variables in that file.

man on ndd will explain a bit more.

Cheers
Con.

[Michael Steele_2]

'ndd' is a network cofiguration command that emerged in HP-UX 11.00 and is used for network 'tuning'. For the tuning to survive through reboots the 'nddconf' file is used. /etc/nddconf is read during bootup.

To get a list of all TCP related parameters:

ndd -get /dev/tcp ?

To use the command line syntax:

ndd -get /dev/ip ip_ire_gw_probe (* to list current value *)

ndd -set /dev/ip ip_ire_gw_probe 0 (* to set *)

http://docs.hp.com/cgi-bin/fsearch/framedisplay?top=/hpux/onlinedocs/B9106-90008/B9106-90008_top.html&con=/hpux/onlinedocs/B9106-90008/00/02/253-con.html&toc=/hpux/onlinedocs/B9106-90008/00/02/253-toc.html&searchterms=parameters%7clist%7cndd&queryid=20030611-220259

[Michael Steele_2]

Yes, comment out:

ndd -set /dev/ip ip_send_source_quench 0

This is the command line version of the above three lines and is unreadable.

[T G Manikandan]

ndd is for network tuning.

check for the man pages of ndd.

For making the changes persistent the nddconf file is used.


Revert

[Nikee Reddy]

Hello folks,

Thanks for the response.

I have one last quick question.

I ran the following command:
ndd -get /dev/ip ip_send_source_quench

In some of my systems returned a value '0' and in some system retuned a value '1'. What's the meaning for '0' and '1'???

Thanks.

Best regards,
Nikee

[Bill Douglass]

Source Quench messages are ICMP messages from a receiving host to s sending hos or gateway requesting that the flow rate on traffic be cut back some. It is designbed to help out a receiving host that is receiving more LAN traffic than it can handle.

Set to 0, your system will not respond with source quench messages when the network traffic starts to build up. Set to 1 and it will send SQ messages to the sending host/gateway.

HP-UX 11.0 has a bug in its implementation that can cause the receiving host to send excessive SQ messages when it is not necessary. I have one host that does this, so I put an entry similar to the above to disbale the SQ messages. This makes our router guys happier (no flood of ICMP error messages).

Most hosts do not exhibit this problem, and so leave SQ enabled.

See also this discussion from a few years back:

http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xa041af48a9e5d5118ff40090279cd0f9,00.html

[Con O'Kelly]

Hi

Generally 'O' means its disabled and '1' that it is enabled.
I think by default ip_source_send_quench is enabled.
For the systems that show 0 there is probably an entry in nddconf file.

Cheers
Con

[rick jones]

sigh, all those comments in the nddconf file itself about format and such, and still someone tries to put direct commands in there...

ftp://ftp.cup.hp.com/dist/networking/briefs/annotated_ndd.txt