Troubleshooting & Diagnostics

This error typically occurs when the GeoServer process is not running or the port is blocked by a firewall.

Steps to resolve:

1. Check if the service is running: systemctl status geoserver
2. Verify port availability: netstat -tuln | grep 8080
3. Check firewall rules and allow inbound traffic on port 8080.
4. Review WEB-INF/logs/geoserver.log for startup errors.

When tiles appear blank or show only grid lines, this usually indicates a rendering issue or data path error.

Common causes:

• Incorrect SRS/CRS settings on the layer.
• Style file (SLD/SLPP) syntax errors.
• Data source connectivity loss.
• OOM (Out of Memory) errors during rendering.

geoserver.log
ERROR: Rendered exception
org.geotools.styling.StyleException: Failed to parse SLD
  at com.sun.org.apache.xerces.internal.parsers...

Check the WMS GetMap request in browser dev tools (Network tab) and enable "Debug output" in GeoServer global settings.

GeoServer is Java-based and can be memory-intensive. High usage often stems from:

• Large feature sets without proper indexes.
• Complex vector tiles or high-resolution raster processing.
• Java Heap size limits reached.

Recommendations:

export JAVA_OPTS="-Xms2g -Xmx4g -XX:MaxMetaspaceSize=512m"
# Add to startup script or systemd service file

If the UI keeps redirecting to login or returns 401 Unauthorized, check your security configuration.

Verify that web.xml security constraints are correctly mapped and that the Authentication plugin is enabled in the admin panel.

If using LDAP/Active Directory:

• Ensure network connectivity to the AD server.
• Check bind DN credentials in the GeoServer security settings.
• Validate group mappings.

Shapefiles often contain invalid geometries that GeoServer cannot ingest directly.

Solution:

shp2pgsql -c -D -s 4326 input.shp schema.table | psql -d yourdb

Or use QGIS to validate and fix geometries before publishing. Ensure all required shapefile components (.shp, .shx, .dbf, .prj) are present.

Large feature queries via WFS can exceed default timeout thresholds.

Increase the timeout in web.xml or use Feature Pagers to stream results incrementally.

<init-param>
  <param-name>request.timeout</param-name>
  <param-value>120000</param-value>
</init-param>