OHD/HL - RFCDEV/LINUX: operation description

rev 03/08/02- 02/05/02

2^nd Draft - Project Description

River Forecast Center Operational Backup Using LINUX PCs

1) Scope of Project

There are many possible configurations for addressing RFC computational backup requirements. This is because there are an almost infinite number of outage or failure scenarios. The table in Section 2, Backup Scenarios, outlines some of the possible failure scenarios and lists configurations that may be used to address each situation.

The NWS is currently fielding LINUX PCs (two per RFC, LX1 and LX2) that will be configured as a part of the standard AWIPS installation. The LX1 and LX2 AWIPS configuration provides only a very limited backup capability, if one chooses to even call it backup. For the most part, LX1 and LX2 depend on the standard AWIPS server configuration of the data ingest function as well as the Informix installation on these servers to feed the LINUX port of NWSRFS. The data ingest function and Informix database do not actually reside on the LINUX platforms themselves. Other functions such as OFS_DE also run on the servers, with output from the processes being made available to LX1 and LX2. The LINUX PC configuration in AWIPS does not provide for a stand-alone forecast system functionality. Therefore the only backup functionality filled by LX1 and LX2 is to basically serve as two additional AWIPS "seats" for the situation where some number of AWIPS workstations may become inoperable. However, the server functionality of AWIPS must remain operational.

The goal of this project is to develop a basic stand-alone NWS Southern Region RFC operational forecast system backup capability that is independent of AWIPS. The system will provide automated data ingest, data display and monitoring, batch and interactive river forecast model, product composition and product dissemination capabilities. Configurations that provide this stand-alone capability are indicated as items 1.b.iii., 2.b.iii., 3.b.iii. and 4 of the table in Section 2. Those configurations will be initially prototyped by ABRFC and it is anticipated ABRFC will use one of those configurations as it's final backup configuration. Other RFCs may choose a different configuration. Functionally situated between the standard AWIPS LX1/LX2 configuration and the prototype stand-alone system are various intermediate configurations. These intermediate configurations can be implemented and retained in order to provide for various levels of backup capabilities or scenarios, as well as being useful in routine operations. These intermediate configurations could utilize certain switchable connections to AWIPS such as data ingest or data dissemination components. The backup system could serve as an extra operational workstation or could serve as the operational system during AWIPS upgrades or other maintenance outages. The concept of this design approach is that it should increase the probability of project success because a backup system that is a useful part of routine RFC operations is also a backup system that has an excellent chance of being in a high state of readiness. However, there are some significant issues to resolve before this capability is realized. These issues will be outlined in Section 4 of this document.

2) Configurations for Various Backup Scenarios

The table below outlines possible configurations for PC backup equipment and associated data paths for various backup scenarios.

3) Functional Design Considerations

This project will rely on a PC(s) as the primary computational device. The PC(s) will use the LINUX operating system and the Informix RDBMS. The project will utilize available computing resources as much as possible since a specific funding source for equipment has not been identified. The backup capabilities need to address requirements for ease of transition to backup systems from operational systems (and vice-versa), data access, data preparation, monitoring, analysis and dissemination, river forecast model execution and other software computational requirements. The project must meet identified backup requirements for desired levels of degraded equipment and facility situations. The project should also consider use of the backup system by personnel not assigned to the affected RFC.

The base configuration to be prototyped by ABRFC at the beginning of this project will be for a single PC performing all backup functions. Data ingest will initially be via ABRFC LDAD and finally via Internet. Data dissemination will initially be via ABRFC LDAD. Once the data dissemination using ABRFC LDAD is successful, the LDAD configuration for dissemination will be tested at a WFO. Finally the data dissemination will be via Internet.

The functionality of the baseline prototype includes the following.

1. IHFS Database using Informix RDBMS

2. Shefdecoder (i.e., parse & post)

3. Raw DPA file UNIX to LINUX binary file converter

4. NWSRFS OFS (i.e., batch model)

5. IFP

6. Data Ingest via Internet. Includes DPAs, HADS, Coop network and other SHEF data available on AWIPS WAN and other agencies such as Corps.

7. OFS_DE & Batchpost

8. xapps including xnav, xdat and xsets (including fcst_prog)

9. P1/P2 88-D precipitation processing system

10. send_wan functionality

11. IHABBS

Certain additional functionality is highly desirable but is not included in the planning for the baseline system initially being prototyped by ABRFC. Since several items are outside the control of the Project Team and/or ABRFC does not sufficient resources to address each one, it has not been decided if implementing these items are within the scope of the project through the September 30, 2002 time frame. The full SR RFC PC Backup Team must discuss and address these issues. The items or functions not planned for inclusion in the ABRFC baseline prototype include the following.

1. NMAP or other QPF processing functionality

2. MPE

3. D2D

4. FOP and RFO

5. NWSRFS fs5files binary file conversion utilities for warm-start of NWSRFS from AWIPS on the backup system and vice-versa

6. OFS data restore

4) Initial Unresolved Issues

The initial configuration to be prototyped by ABRFC does not include all desired functionality. The issues related to this situation are outlined and discussed below.

a) NMAP or other QPF processing functionality - NMAP will not run on the standard AWIPS LX1/LX2 hardware. NWS HQ is considering using IFPS/GFE as the standard QPF processing tool. Therefore resolution of this issue is totally out of the scope of the Project Team.

b) MPE - ABRFC will not include this program in the initial baseline prototype system. It is anticipated that another group in the Project Team will resolve the issue of implementing MPE.

c) D2D - ABRFC will not include this program in the initial baseline prototype system. It is anticipated that another group in the Project Team will resolve the issue of implementing D2D which jas been thoroughly tested in other LINUX configurations.

d) FOP and RFO - The ABRFC RFO front-end GUI could be ported to LINUX. However, ArcView is not available on LINUX. Therefore, resolution of this issue is totally out of the scope of the Project Team.

e) NWSRFS fs5files binary file conversion utilities for warm-start of NWSRFS from AWIPS on the backup system and vice-versa - OHD consumed considerable resources in addressing this issue during the NWSRFS AWIPS port. They determined it necessary to require cold start of the NWSRFS on LINUX using ASCII "card deck" formats versus not meeting the NWSRFS AWIPS port deadline due to the extreme complexity of the binary file converter software. ABRFC anticipates that a "warm-start" capability will be fulfilled by running NWSRFS in the AWIPS LX1/LX2 environment and then using a copy of the LX1/LX2 fs5files on the LINUX PC backup system for "warm-start" of the model.

f) OFS data restore - This functionality is deemed initially to be non-critical because of the anticipated success of the "warm-start" procedure identified above.

g) Informix - A funding source for additional Informix licenses has not been identified. ABRFC is using an Informix license in testing mode and is using the "if we build it, they will come" attitude for the initial prototype. This must be resolved for successful implementation. If funding is not forthcoming for Informix licences, ABRFC is prepared to pursue testing of an Informix engine clone that could very easily be purchased with local funds.

h) ArcView - ArcView is not available for LINUX. If and when it becomes available, a funding source for LINUX ArcView licenses has not been identified. FPO and RFO products may not be produced in backup mode unless a workaround on a windows PC or the AWIPS is designed and implemented.

i) PC hardware - A funding source for required hardware has not been identified. ABRFC anticipates using the local office budget as a funding source.

5) Future Considerations

a) Multiple backup PC workstations - A funding source for required hardware has not been identified. It is desirable that the design eventually address this issue of providing multiple workstations.

b) Backup Server Configuration - After all functionality is tested, it may be necessary due to performance considerations to provide a server PC to host Informix, perform data ingest or other functions.

c) Alternate data source - It is desirable to investigate data sources such as EMWIN, in addition to AWIPS and the Internet.