A major change this summer was the replacement of the main IDD source machine thelma.ucar.edu to motherlode.ucar.edu. The acquisition of motherlode was described in the Summer/Fall 1999 issue of the Unidata Newsletter. It is the result of a joint project between Unidata and NCAR's Scientific Computing Division (SCD) to provide an archive of IDD products, convenient access to critical data sets in SCD's Mass Storage System, a McIDAS ADDE server, a DODS server, and other new ways to access remote data. The motherlode machine is a Sun E450, with 4 450 Mhz processors, 4 GB of memory, redundant power supplies, and 500 GB of disk. It sits on the network directly connected to the vBNS by one router. It's currently running LDM version 5.1.2.
Tuesday July 25, 2000, the IDD had problems caused by power and network outages at NCAR. The UPC determined that changes to the top-level sites and a more robust failover plan were needed. One major change is that there is now an external site available for all the top level sites. If another problem should occur with the UCAR network, the top levels sites now have a failover outside the UCAR domain.
To enhance the reliability of the IDD, a web page with failover instructions was created. The page also includes the configuration of the NOAAport source sites, plus instructions for all sites in the IDD topology. This page will be updated as changes occur and UPC will notify the community. This page is located under:
IDD page
Current operational status
IDD failover scheme
http://www.unidata.ucar.edu/projects/idd/failover.html
Because of Alden's recent financial problems this summer, the use of the Alden source machine has been eliminated from the IDD topology without any ill affects. I have done the LDM maintenance for the machine for the last 2 years so I have considered it as a remote UPC machine. The Alden's machine position in the IDD topology has been replaced with the Weather Underground machine "sleet.wunderground.com" Therefore the top level source ring is still in place and the robustness remains the same. Also, the LSU NOAAport ingestor has recently come online within the last week as another top level source node. At this time, it's configuration is not completed.
The IDD topology changes since the last Polcomm meeting, 5 new sites and 23 feed type reconfigurations. Jeff Weber is now in charge of the IDD configurations and he is planning on getting more sites to implement the LDM statistics program so the IDD routing topology charts will be more current.
New Stanford Nevada Center for Advanced Computational Methods FNMOC Embry-Riddle (Prescott) West Chester University Re-arrange status: Lyndon State U of Michigan U of Oregon UIUC Metro State U of Utah PSU St Cloud State Texas A&M Wisconsin Wyoming Mich State Plymouth State State University of New York at Stony Brook Missouri-Columbia Univeristy of Alabama in Huntsville U of Washington St Louis University U of Miami Princeton U of Kansas UCAR/COMET LSU