Indexer failures

Hi All,
We have Graylog 2.1. and we have a lot of Indexer failures.
I have read, but there is nothing how to debug it or how to solve this problem.

I think this log is from windows servers, there is nxlog and collector sidecar.
What should I do to fix these issues?
Is it possible to use “Letter ID” in order to see message which failed to be indexed, or is there any other way to do that?
Thanks in advance,

MapperParsingException[failed to parse [protocol]]; nested: NumberFormatException[For input string: “WSMan”];

Hej @lubos
your resolution is written on the page that you put the link in your posting


This can be triggered by for example sending GELF messages with different field types or extractors trying to write strings without converting them to numeric values first. The recommended solution is to actively decide on field types. If you sent in a field like http_response_code with a numeric value then you should never change that type in the future.

The Solution, create a custom index mapping.

Thanks for your reply