Re: UDP Packet are lost

From: Joe Durusau (joseph.a.durusau_at_lmco.com)
Date: 05/06/03 

Date: Tue, 06 May 2003 11:16:49 -0400

JaakovB wrote:
>
> Hi all,
>
> I'm working on solaris 8 on server like U60, R280 and developping a SNMP
> manager application. The compiler we use is SUN Forte 6.1 for C++.
>
> Even if I know that UDP is not a reliable protocol and theorically packets
> may be lost,
> my problem is that we are losing a lot of UDP packets.
>
> So my problem is that we loose packets. Those packets have been sent by the
> remote machine (we saw it with a sniffer installed on a PC connected on the
> same segment), but never arrived on my SUN machine. In the same time another
> PC also connected on the same segment got all the UDP packets.
> Another problem is that the 'snoop' tools seems to be not trustable because
> packets
> received by our application weren't catched by snoop !!!
>
> So I have tow questions:
> - is there any special configuration on my Solaris that can explain I
> lose UDP ?
> - is there any tools that I can use on my Solaris to sniff packet or
> trace UDP activity ?
>
> This problem is very critical, and we have currently no idea how to solve
> it.
>
> Thanks for any tips.
>
> Yaakov Berkovitch
> mailto:jaakovb@corrigent.com

You do one of the following:

1). Don't user UDP for a critical app.

or

2). Install some higher level routine that will detect and compensate
when packets are lost.

The loss of packets in UDP is not theory, it's practice, except possibly
for AF_UNIX sockets.

Speaking only for myself,

Joe Durusau

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