Capturar logs do Farm através de 1 servidor via PowerShell

Merge-SPLogFile -Path <String> [-Area <String[]>] [-AssignmentCollection <SPAssignmentCollection>] [-Category <String[]>] [-ContextFilter <String[]>] [-Correlation <Guid[]>] [-EndTime <DateTime>] [-EventID <String[]>] [-ExcludeNestedCorrelation <SwitchParameter>] [-Level <String>] [-Message <String[]>] [-Overwrite <SwitchParameter>] [-Process <String[]>] [-StartTime <DateTime>] [-ThreadID <UInt32[]>]

Exemplo:

Merge-SPLogFile -Path D:\merged_log.log -Correlation 9b6b1653-baef-46a4-ace8-ff9a1f535f87

Referência:

http://technet.microsoft.com/en-us/library/ff607721.aspx