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Hi Dan, Glenn: java.net.SocketException: Connection reset probably means that the socket was closed on the server.To go further with this we need to look at the threddsServlet.log files and see if we are getting any error messages in there that correspond to what Gerald is seeing. this may be hard without knowing the exact URL and a small time window during which the errors happened, and maybe the client IP address. Gerald do you have any of that?
this can also happen when the connection gets very slow, eg if one of the IP routes is flaky. Gerald can you ask your network guys (if you have them) to test to see if your network routing to nomads has any problems?
On 4/23/2010 6:59 AM, Dan Swank wrote:
John, This addy is for NCDC-NOMADS servers nomads.ncdc.* only. For NCEP-NOMADS ~ you should contact their HelpDesk: @ http://nomads.ncep.noaa.gov/txt_descriptions/Help_Desk_doc.shtml -Dan address@hidden wrote the following on 4/22/2010 8:41 PM:hmm- John can you assist here? thx, glenn ----- Original Message ----- From: Gerald Spreitzhofer<address@hidden> Date: Thursday, April 22, 2010 4:28 pm Subject: Re: [Fwd: Re: problems reading GFS data from NOMADS-HD; DConnect]Thanks, John. Glenn, could you please answer my mail or explain me the error messages I am receiving from time to time (see below)? I think there were similar messages some days in fall, some people from the mailing list complainedand then you were able to fix them. Best regards, Gerald On Do, 22.04.2010, 22:18, John Caron wrote:gerald, send reports to address@hidden On 4/22/2010 12:54 PM, Gerald Spreitzhofer wrote:John, I am having the same problems as before and the same errormessage (seebelow, java.net.SocketException) most of the day, usingDODS/OPENDAP.>> Alsojust clicked again on the motherlode-link, there I can download GFS 0.5deg data (well, some gridpoints, I did not check for big amounts ofdata).>> Theamount of data I am downloading is max. 20 MB (like always), Idon't>> thinkthis is a problem. The error usually ocurs some time during the downloading, not just at the beginning. Can you forward this mail to persons who might help? Thanks, Gerald On Mo, 19.04.2010, 16:44, john caron wrote:gerald, can you try hitting datasets on http://motherlode.ucar.edu/thredds/ and see if you have anyproblems?>>>Gerald Spreitzhofer wrote:Hi John, Thanks for answering my mail last Friday that quickly.Problems stillpersist, but it looks like they are not permanent (sometimes in between GFS data can be read without problems). Maybe the errormessages belowhelp (they were produced this morning around 8 UTC). Best Regards, Gerald ===== Reading 3d-variable 58: pressfc===== java.net.SocketException: Connection reset at java.net.SocketInputStream.read(SocketInputStream.java:168) atjava.io.BufferedInputStream.fill(BufferedInputStream.java:183)>>>> at java.io.BufferedInputStream.read1(BufferedInputStream.java:222)atjava.io.BufferedInputStream.read(BufferedInputStream.java:277)>>>> at sun.net.www.http.HttpClient.parseHTTPHeader(HttpClient.java:741)at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:702) at sun.net.www.http.HttpClient.parseHTTP(HttpClient.java:712) atsun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:583)>>>> at dods.dap.DConnect.openConnection(DConnect.java:174)at dods.dap.DConnect.getDataFromUrl(DConnect.java:380) at dods.dap.DConnect.getData(DConnect.java:339) at dods.dap.DConnect.getData(DConnect.java:522) atucar.nc2.dods.DODSNetcdfFile.readDODSData(DODSNetcdfFile.java:536)>>>> at ucar.nc2.dods.DODSVariable.readDODSData(DODSVariable.java:497)at ucar.nc2.dods.DODSVariable.read(DODSVariable.java:393) at SEVIS.NetcdfUtil.readNcArrayLayer(NetcdfUtil.java:1846) at SEVIS.NetcdfUtil.readNcArray(NetcdfUtil.java:1708) atSEVIS.NetcdfUtil.readNcArray_0MedAdapted(NetcdfUtil.java:1659)>>>> at SEVIS.DODSReader.writeNcVariables(DODSReader.java:825)at SEVIS.DODSReader.createNetcdfFile(DODSReader.java:676) at SEVIS.DODSReader.<init>(DODSReader.java:159) at SEVIS.SuperDataFile.getDodsFile(SuperDataFile.java:2526) atSEVIS.SuperDataFile.getSpecifiedNetcdfFile(SuperDataFile.java:2344)>>>> at SEVIS.MainFrame.forecastUpdate(MainFrame.java:2131)atSEVIS.MainFrame.jButtonDataUpdate_actionPerformed(MainFrame.java:2163)>>>>------------------------ Ursprüngliche Nachricht ------------------------ Betreff: Re: problems reading GFS data from NOMADS-HD; DConnect Von: "Glenn Rutledge"<address@hidden> Datum: Fr, 16.04.2010, 19:41 An: "John Caron"<address@hidden> Cc: "Gerald Spreitzhofer"<address@hidden> address@hidden --------------------------------------------------------------------------Thanks John, We don't seem to be experiencing any issues. I've cc:ed DanSwank>>>> hereand he might be able to track down this issue. Regards, Glenn John Caron said the following on 4/16/2010 1:01 PM:Hi gerald: im not having any trouble with that URL. is it still happening (11 am MST) ? On 4/16/2010 10:15 AM, Gerald Spreitzhofer wrote:Hi John, I am operationally reading GFS 0.5deg data from the NOMADS-HD servervia DODS and the Java/NetCDF library. I did not change anythingin mycode during the last couple of months, but recently (for instancethe>>>>>> last20 hours) there have been some errors reading data from there(see theprotocol below). I think I remember that there was a similarproblem>>>>>> lastfall, and the reason was a change in some security or firewall setting on NOMADS, just concerning this protocol. Do you know what thereason>>>>>> for themessages can be or who might be responsible? Thanks, Gerald ===== Reading 3d-variable 28: hgtsfc===== DConnect getData failed; retry (1,100)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[5:5][250:299][704:719]>>>>>>DConnect getData failed; retry (2,200)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[5:5][250:299][704:719]>>>>>>DConnect getData failed; retry (3,400)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[5:5][250:299][704:719]>>>>>>DConnect getData failed; retry (4,800)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[5:5][250:299][704:719]>>>>>>DConnect getData failed; retry (5,1600)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[5:5][250:299][704:719]>>>>>>DConnect getData failed; retry (1,100)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[0:0][250:299][0:66]>>>>>>DConnect getData failed; retry (2,200)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[0:0][250:299][0:66]>>>>>>DConnect getData failed; retry (3,400)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[0:0][250:299][0:66]>>>>>>DConnect getData failed; retry (4,800)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[0:0][250:299][0:66]>>>>>>DConnect getData failed; retry (5,1600)http://nomads.ncep.noaa.gov:9090/dods/gfs_hd/gfs_hd20100415/gfs_hd_18z.dods?hgtsfc[0:0][250:299][0:66]>>>>>>----------------------------------------- Dr. Gerald Spreitzhofer, Researcher Institute of Meteorology and Geophysics University of Vienna A-1090 Vienna, Althanstrasse 14, UZA2 Tel.: +43-1-4277-537 33 email: address@hidden -----------------------------------------