[Gluster-devel] bit rot support for glusterfs design draft v0.1

[Chris Murphy]

On Jan 26, 2014, at 10:30 PM, shishir gowda <gowda.shishir at gmail.com> wrote:

> Phase 1: File level bit rot detection
> The initial approach is to achieve bit rot detection at file level,
> where checksum is computed for a complete file, and checked during
> access.

[…]

> Upon access (open for non-anonymous-fd calls, every read for
> anonymous-fd calls) from any clients, the bit rot detection xlator
> loaded ontop of the bricks, would recompute the checksum of the file,
> and allow the calls to proceed if they match, or fail them if they
> mis-match. This introduces extra workload for NFS workloads, and for
> large files which require read of the complete file to recompute the
> checksum(we try to solve this in phase-2).

Does the proposal detect corruption that occurs at the network layer between a (brick) server and client? Perhaps my reading is mistaken, but if bitd runs on the server, and bit rot detection xlator is also on the server to recompute checksum, then network induced corruption isn't detectable. 

Chris Murphy