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Re: Top level CONDUIT relay

I think the time_wait was just a connection reset / perhaps a link
faiture or reset was sent.  The itme_wait were in fin_wat state 2 for a
while then timed out like any other normal tcp application.   Current
netstat

tcp        0      0 ncepldm.woc.noaa.go:388 flood.atmos.uiuc.:60281
ESTABLISHED
tcp        0      0 ncepldm.woc.noaa.go:388 flood.atmos.uiuc.:60283
ESTABLISHED
tcp        0      0 ncepldm.woc.noaa.go:388 flood.atmos.uiuc.:60287
ESTABLISHED
tcp        0      0 ncepldm.woc.noaa.go:388 flood.atmos.uiuc.:60276
ESTABLISHED
tcp        0      0 ncepldm.woc.noaa.go:388 flood.atmos.uiuc.:60278
ESTABLISHED
tcp        0      0 ldm1.woc.noaa.gov:388   atm.cise-nsf.gov:58640 
ESTABLISHED
tcp        0      0 ldm1.woc.noaa.gov:388   atm.cise-nsf.gov:58639 
ESTABLISHED
tcp        0      0 ldm1.woc.noaa.gov:388   atm.cise-nsf.gov:62105 
ESTABLISHED
tcp        0      0 ldm1.woc.noaa.gov:388   atm.cise-nsf.gov:62090 
ESTABLISHED
tcp        0      0 ldm1.woc.noaa.gov:388   atm.cise-nsf.gov:62123 
ESTABLISHED
tcp        0      0 ldm1.local:388          node6.local:34593      
ESTABLISHED


Steve Emmerson wrote:
> Chi,
>
> Steve Chiswell wrote:
>> The netstat listing that you showed with several LDM connections in
>> time_wait
>> may mean somethng to Steve Emmerson and/or Mike Schmidt, so I'll see
>> if they
>> have any imput as well as suggestions on TCP tuning.
>
> > tcp        0      0 ldm1.woc.noaa.gov:388   atm.cise-nsf.gov:61678
> TIME_WAIT
> > tcp        0      0 ncepldm.woc.noaa.go:388 flood.atmos.uiuc.:48265
> TIME_WAIT
>
> The "netstat" output indicates that LDM processes on hosts
> atm.cise-nsf.gov and flood.atmos.uiuc established TCP connections to
> the LDM server on the local host (alias ldm1.woc.noaa.gov and
> ncepldm.woc.noaa.go) and that the corresponding LDM process on the
> local host closed the connections.  See
> <http://www.ssfnet.org/Exchange/tcp/tcpTutorialNotes.html>.
>
> I can imagine several situations in which this would occur.  The first
> is when the remote hosts are not allowed to connect -- in which case
> the top-level LDM server on the local host would close the TCP
> connection. Check the LDM configuration-file, etc/ldmd.conf, to ensure
> that both atm.cise-nsf.gov and flood.atmos.uiuc are allowed to
> connect.  You could also put the top-level LDM process on the local
> host into verbose logging mode (see
> <http://www.unidata.ucar.edu/software/ldm/ldm-current/basics/logfile-format.html>).
>
>
> Another situation is when a downstream LDM is not allowed to received
> the data that it is requesting.  In this case, the upstream LDM
> process on the local host should log a warning-level message.
>
> The last situation is when an upstream LDM process on the local host
> tries to send an RPC message to the downstream LDM for which it
> expects a reply and the wait for the reply times-out.  Again, the
> upstream LDM process should log a message.
>
> Regards,
> Steve Emmerson


-- 
Chi Y. Kang
Contractor
Principal Engineer
Phone: 301-713-3333 x201
Cell: 240-338-1059