Snort 2.9.0.1 includes two new tools, u2spewfoo and u2boat, which reads Unified2 output files and output them as text. The second tool transforms the pcap data in a Unified2 file into a normal pcap file. I guess that’s good for troubleshooting, but fortunately unless I fix Barnyard2 or a fix is committed it will die when it encounters record types from Snort that Barnyard 2.2 doesn’t recognize, e.g. Snort.”]
Source: https://taosecurity.blogspot.com/2010/11/two-new-tools-in-snort.html