Either pipeline_beat.config or pipeline_nmap.config has a syntax error. By the looks of it the problem is at the very beginning. Perhaps you've edited the files with an editor that adds a byte-order mark? You can check this with a hex editor.
The pipelines.yml file should be placed in the settings folder, and can as far as I know not be passed through the -f flag. Place the file in the correct location and then try starting Logstash without the -f flag.
Gentlemen, thank you for your responses. The pipeline.yml is in the config folder, I should have made my example more clear. As for the editor, I used Notepad++, I'll look into the byte mark ordering. I could see the error was telling me it didn't like the first instruction it saw in the file, but the syntax makes it seem like it's not compatible with multi-pipelining.
Did some Googlin' and Notepad++ has two encoding settings, UTF-8 and UTF-8-BOM. All my config files are using UTF-8 encoding, so that doesn't appear to be the issue either. I also verified that UTF-8-BOM does not mean UTF-8 without BOM.
Any other ideas? Anything else about my setup you need to help me with the issue?
I am not using a modified path.settings configuration, everything resides in the \logstash\config folder. I have tried running with the custom pipeline config files in logstash\config\pipelines folder and with them in the \logstash\config folder, both have the same behavior.
Ah, I see what you're saying....which is odd because, as I said in the post you are quoting, by removing the drive letter, the issue was resolved. This thread is specifically about Windows installations, where full paths have drive letters so I could see where you could be confused if you thought I was talking about Linux.