topic Using UDP protocol in Operating System - Linux

Using UDP protocol

Jagadesh — Tue, 15 Jun 2004 03:01:03 GMT

Dear All,

I need to use UDP to test one of my application. Can i specify the same in /etc/services? or do i have to do any other changes?

Kindly help me out in this regard.

Thanks
Jagadesh

Re: Using UDP protocol

U.SivaKumar_2 — Tue, 15 Jun 2004 03:07:55 GMT

Hi,

if you refer portname anywhere in your application , you have to define the portname-portnumber mapping in /etc/services for the application to bind to that port.

if the application is using port number directly to bind, there is no need for /etc/services entry. you can straightaway start the application.

regards,

U.SivaKumar.

Re: Using UDP protocol

Jagadesh — Tue, 15 Jun 2004 04:12:08 GMT

After mentioning in /etc/services how can i check whether the same is using UDP or not?

Thanks

Re: Using UDP protocol

Stuart Browne — Tue, 15 Jun 2004 18:06:37 GMT

You've not been terribly clear on exactally what you're wanting to do.

Are you trying to see if your application is sending UDP traffic? Or accepting UDP traffic?

Either way, you have a few options available.

If you want to see if it's sending/receiving UDP traffic, the 'tcpdump -n udp port ' command should show you.

If you want to see if your application is listening for UDP traffic on a defined port, use the 'netstat -nulp' command.

As UDP is a stateless protocol, using 'netstat -na' won't show you anything useful that the other netstat command wouldn't.

If it's neither of these, can you please clear up exactally what you're trying to achieve.

Re: Using UDP protocol

Guru Dutta — Mon, 21 Jun 2004 05:15:24 GMT

use netstat -p for knowing which protocol your application is using.

Re: Using UDP protocol

Bharat Katkar — Mon, 21 Jun 2004 07:57:49 GMT

Hi jagadesh,
You can use rpcinfo command to check the if any particular service is up or not.

Regards,

p.s. Seen this in your profile. "I have assigned points to 56 of 295 responses to my questions." Keep assigning points to the replies that really helped.