* **Geospatial projection** must be defined in a [***grid navigation file***](#create-grid-projection-file)
* **Grid name**, **center**, **subcenter**, and **process ID** must be defined in a [***model definition file***](#create-model-definition)
If the parameters in the grib file haven't been previously specified, another change *may* be needed as well:
* **Center**, **subcenter**, **discipline**, **category**, and possibly **parameter ID** information may need to be defined in a [***table***](#adding-a-table)
Remember that the data distribution file (`/awips2/edex/data/utility/common_static/base/distribution/grib.xml`) will match filenames which have the `*.grib*` extension.
Remember that the data distribution file (`/awips2/edex/data/utility/common_static/base/distribution/grib.xml`) will match filenames which have the `*.grib*` extension.
2. Confirm that the grib file decodes in the grib log file:
edex log grib
INFO [Ingest.GribDecode] /awips2/data_store/ingest/cpti.grib2 processed in: 0.1200 (sec) Latency: 21.8080 (sec)
INFO [Ingest.GribDecode] /awips2/data_store/ingest/cpti.grib2 processed in: 0.1180 (sec) Latency: 21.8140 (sec)
INFO [Ingest.GribDecode] /awips2/data_store/ingest/cpti.grib2 processed in: 0.4230 (sec) Latency: 21.8360 (sec)
INFO [Ingest.GribDecode] /awips2/data_store/ingest/cpti.grib2 processed in: 0.2240 (sec) Latency: 21.9140 (sec)
...
**Note:** This step will likely fail, because the parameter is not yet defined. The error will look like:
INFO 2020-07-20 20:34:17,710 2565 [GribPersist-1] GridDao: EDEX - Discarding record due to missing or unknown parameter mapping: /grid/2018-05-02_00:01:44.0_(0)/GribModel:161:0:97/null/null/403/Missing/FH/500.0/-999999.0
INFO 2020-07-20 20:34:17,827 2567 [Ingest.GribDecode-6] grib: EDEX - No parameter information for center[161], subcenter[0], tableName[4.2.209.3], parameter value[61]
In order to successfully ingest the example file, [**define the appropriate table**](#grib2-products_4).
3. Check that the hdf5 data directory exists for our unnamed grid
ls -latr /awips2/edex/data/hdf5/grid/GribModel:161:0:97
Though the grib file has been decoded, it has been given a generic name with its center, subcenter, and process IDs (161, 0, 97, respectively).
When the grid was ingested a record was added to the `grid_coverage` table with its navigation information:
psql metadata
metadata=# select nx,ny,dx,dy,majoraxis,minoraxis,la1,lo1,lov,latin1,latin2 from gridcoverage where id=(select distinct(location_id) from grid_info where datasetid='GribModel:7:0:89');
Compare with the projection info returned by wgrib on the original file (look at the bolded sections below and make sure they match up with the corresponding entries returned from the database above):
<!--
Using html for this code block so that certain sections within the code can be emphasized (bolded)
North Pole (201 x 155) <b>Dx 4.297000 Dy 4.297000</b> scan 64 mode 8
min/max data 5 21.9 num bits 8 BDS_Ref 50 DecScale 1 BinScale 0
</pre>
Notice that our grib file has a **Lambert Conformal** projection. We will need these values for the next step. Note that **there is a tolerance of +/- 0.1 degrees** to keep in mind when defining your coverage area.
metadata=# select nx,ny,dx,dy,majoraxis,minoraxis,la1,lo1,lov,latin1,latin2 from gridcoverage where id=(select distinct(location_id) from grid_info where datasetid='GribModel:161:0:97');
Compare with the projection info returned by wgrib2 on the original file (look at the bolded sections below and make sure they match up with the corresponding entries returned from the database above):
<!--
Using html for this code block so that certain sections within the code can be emphasized (bolded)
-->
<pre>
wgrib2 -grid -nxny cpti.grib2
1:0:grid_template=0:winds(N/S):
<b>lat-lon grid:(600 x 640)</b> units 1e-06 input WE:NS output WE:SN res 48
lat <b>40.799999</b> to 37.599999 by <b>0.005000</b>
lon <b>260.999999</b> to 263.999999 by <b>0.005000</b>#points=384000:(600 x 640)
...
</pre>
Notice that our grib2 file has a **Lat/lon Grid** projection. Where:
* **nx** is **600**
* **ny** is **640**
* **dx** is **0.005**
* **dy** is **0.005**
* **la1** is **40.799999**
* **lo1** is **261**
We will need these values for the next step. Note that **there is a tolerance of +/- 0.1 degrees** to keep in mind when defining your coverage (la1 and lo1) area.
And edit the new `wrf.xml` to define the projection values using the [output from wgrib or the database](#determine-grid-projection) (example provided):
> **Note**: Notice the `<name>201155</name>` tag was defined from the number of grid points (201 and 155). This value will be matched against an entry in our models file (below) to set the name of the model (e.g. WRF).
### Grib2 Products
Copy an existing xml file with the same grid projection type (in this case **latLonGridCoverage**) to a new file `cpti.xml`:
cd /awips2/edex/data/utility/common_static/base/grib/grids/
cp MRMS-1km.xml cpti.xml
And edit the new `cpti.xml` to define the projection values using the [output from wgrib2 or the database](#grib2-products_1) (example provided):
vi cpti.xml
<latLonGridCoverage>
<name>600640</name>
<description>Small domain for CPTI products</description>
> **Note**: Notice the `<name>384000</name>` tag was defined from the number of grid points (600 and 640). This value will be matched against an entry in our models file (below) to set the name of the model (e.g. CPTI).
Now copy the `wrf.grib` file *again* to **/awips2/data_store/ingest/**. If everything is correct we will not see any persistence errors since the grid is now named **WRF** and not **GribModel:7:0:89**.
After you have confirmed that the grid was ingested with the given name, you can [edit the D2D product menus to display the new grid](../cave/d2d-edit-menus.md).
If you ingest a piece of data and the parameter appears as unknown in the metadata database, ensure that the correct parameter tables are in place for the center/subcenter.
The tables are located in **/awips2/edex/data/utility/common_static/base/grib/tables/**. They are then broken into subdirectories using the following structure: **/[Center]/[Subcenter]/4.2.[Discipine].[Category].table**.
### Grib products
The center and subcenter have been identified previously [here](#grib-products) and [here](#grib-products_1), as 7 and 0, respectively. So, the corresponding directory is:
To find the **discipline** of a grib product, you need the **process** and **table** values from the grib file. These are output with the `wgrib -V` command:
If you are using a grib2 file, then you can use either the log output or the `-center`, `-subcenter`, and `-full_name` options on `wgrib2` to get the center, subcenter, discipline, category, and parameter information:
The table would be found in the directory structure using this file's center and subcenter. The center can be found by either:
* Running the following command:
wgrib2 -center cpti.grib2
1:0:center=US NOAA Office of Oceanic and Atmospheric Research
...
And then looking up the corresponding value for "US NOAA Office of Oceanic and Atmospheric Research" at [**this website**](https://www.nco.ncep.noaa.gov/pmb/docs/on388/table0.html), where it happens to be **161**.
**OR:**
* Running the following command:
<pre>
wgrib2 -varX cpti.grib2
1:0:var209_255_1_<b>161</b>_3_61
...
</pre>
Where the 4th argument after "var" is the center id, in this case **161**.
To get the subcenter, simply run:
<pre>
wgrib2 -subcenter cpti.grib2
1:0:subcenter=<b>0</b>
...
</pre>
The subcenter of this file is **0**.
So based on the center and subcenter, the corresponding directory is:
The parameter ID was also listed in that output as **61**. Make sure that specific parameter information is defined in the table:
<pre>
...
56:56:Reflectivity at -20C:dBZ:ReflectivityM20C
57:57:Reflectivity At Lowest Altitude (RALA):dBZ:ReflectivityAtLowestAltitude
58:58:Merged Reflectivity At Lowest Altitude (RALA):dBZ:MergedReflectivityAtLowestAltitude
59:59:CPTI 80mph+:%:CPTI80mph
<b>61:61:CPTI 110mph+:%:CPTI110mph</b>
</pre>
You will have to restart ingestGrib for the changes to take place:
sudo service edex_camel restart ingestGrib
Now you can try [re-ingesting the grib2 file](#grib2-products).
---
## Troubleshooting Grib Ingest
* Make sure the latitude and longitude entries in your coverage specification file match those of your ingested raw grib file. There is a tolerance of +/- 0.1 degree to keep in mind when defining your coverage area.
* If some of the information is unknown, using a grib utility application such as *wgrib* and *wgrib2* can be useful in determining the information that must be added to correctly process a new grib file.
* If you are experiencing `Segmentation fault` errors when running wgrib2, it may be best to install the latest version using the following command:
