It's not clear how to define a custom grok pattern to debug it.
Indications says that One per line, the syntax for a grok pattern is %{SYNTAX:SEMANTIC}, but it's not the truth. The correct way is follow what it's declared in http://grokconstructor.appspot.com/do/match so
On each line you give a pattern name, a space and the pattern
It's not clear how to define a custom grok pattern to debug it.
Indications says that
One per line, the syntax for a grok pattern is %{SYNTAX:SEMANTIC}, but it's not the truth. The correct way is follow what it's declared in http://grokconstructor.appspot.com/do/match soOn each line you give a pattern name, a space and the pattern