Index filesystem structure 

documented here

https://developer.couchbase.com/documentation/server/3.x/admin/Misc/Trbl-indexFileSystem.html

does not cover file format.

existing 

/opt/couchbase/bin/couch_dbdump

utility does not dump it.

[root@customer2couch1 StaticProfile]# /opt/couchbase/bin/couch_dbdump /opt/couchbase/var/lib/couchbase/data/@2i/MetadataStore

Failed to open "/opt/couchbase/var/lib/couchbase/data/@2i/MetadataStore": malformed data in file

we want to be able to peek in there to see if everything is OK.

but do not know the format, please document it?

Maybe there is an utility that can handle it?