Check for discards at udp Recv-Q netstat -a

[Martin Wolff]

Hi,
I am looking for a way to know if the Recv-Q shown at the netstat -a command is discaring or not.
I have seen that the queue increments as traffic arrives heavily from "outside" the server.
Because of some issues at the aplication that retrieves the data, i am suspicious that there may be discards at a queue for a particular udp port (1813 to be precise).
So i would like to know how can i check for discards.

Platforms checked are DS-10 standalone, and DS-25 cluster, running TRU-64 5.1B PK4.

Thanks in advance,
Martin.

[Martin Wolff]

I guess this is the worst time of the year to post a question , jeje :)

[cnb · Accepted solution]

netstat -id will show dropped stats
netstat -s shows all stats

for packet stats #man pfstat.

[Martin Wolff]

Thank you very much,

Using netstat -s, i see now that discards at udp due to "full sockets" are probably the cause of the application issue i am having.

Is there a way to know the size of the UDP buffer, and a way to increase the buffer size?

Thank you very much in advance again,

Martin.

[cnb]

To know the size:

#man UDP

Rgds,

[cnb]

Please ignore my last post. I was thinking of HP-UX!

You might find answers here:

http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/V51B_HTML/ARH9UETE/DLPPNDXX.HTM#buf-size

Rgds,

[cnb]

Martin,

This may be what you're looking for:

http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/V51B_HTML/ARH9GCTE/TNRCLXXX.HTM#udp-recvspace

http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/V40F_HTML/AQ0R3GTE/CHNTXXXX.HTM

http://h30097.www3.hp.com/docs/base_doc/DOCUMENTATION/V40F_HTML/AQ0R3GTE/CHNTXXXX.HTM#net-qlimit

[Martin Wolff]

Thank you very much,
I will have a look at those docs now,
Kr,
Martin.

[Martin Wolff]

Hi, you are right it was all there!!

To see the size of the udp send and receive buffers:

sysconfig -q inet udp_recvspace
sysconfig -q inet udp_sendspace

To see the buffer size limits:

sysconfig -Q inet udp_recvspace
sysconfig -Q inet udp_sendspace

To change the size permanently:

sysconfigdb -a -f stanza_file inet

Where stanza file is like this:

inet:
udp_recvspace = 1024000
udp_sendspace = 1024000

This change is applied at the next reboot,

but using

# sysconfig -r inet udp_recvspace=1024000
udp_recvspace: reconfigured

you can reconfigure the attribute on the fly so you do not have to wait to reboot to get the change done.

Thank you very much for pointing me to those docs!!!!

Kind regards,
Martin.

[cnb]

Glad you were able to locate everything!


Best Regards,
cnb