Hi, Immutability is about rewriting a file (random access). That is massively used by databases for example. On HDFS you can only append new data to file.
HDFS have permission like a Posix File System, so you can remove the 'w' permisson on the file if you want to prevent deletion/overwrite. You can change file default mask on the root folder to create files with the right permissions by default. Regards, Philippe On Thu, Sep 7, 2017 at 9:23 AM, Bram Van Dam <[email protected]> wrote: > Greetings, > > I've been tinkering with HDFS, and I'm a bit confused about its alleged > immutability. Basically, according to the interwebz (and my > interpretation of the documentation), data in HDFS is immutable. > > However, when I tell the HDFS Java client to overwrite an existing file > with garbage, it happily does so without complaining. That doesn't > really match my definition of immutability. > > What I'm looking for is a way to allow users to create (and maybe append > to) files, but *prevent* them from updating/deleting/overwriting data. > One which isn't a client configuration option. Am I missing some kind of > configuration option which enables this sort of behaviour? Or am I > chasing a pipe dream? > > Thanks, > > - Bram > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [email protected] > For additional commands, e-mail: [email protected] > > -- Philippe Kernévez Directeur technique (Suisse), [email protected] +41 79 888 33 32 Retrouvez OCTO sur OCTO Talk : http://blog.octo.com OCTO Technology http://www.octo.ch
