On Wed, 2011-01-12 at 19:30 -0500, Jim Rees wrote: > Trond Myklebust wrote: > > > But section 13 doesn't apply to the block layout server, does it? > > If you are a block layout server, the only valid return value is > > EXCHGID4_FLAG_USE_PNFS_MDS > > 'cos you are clearly not a non-metadata server, and you clearly can't be > a data server. > > Sorry to be dense, this is the first time I've thought about this. > > At the time of the EXCHANGE_ID call, how is the server supposed to know what > kind of layout is going to be negotiated? It doesn't yet know whether the > client is even going to ask for a layout, does it? It doesn't matter. EXCHGID4_FLAG_USE_PNFS_MDS is the server's way of advertising to the client that it supports LAYOUTGET and other pNFS related operations. The client is free to ignore that message if it so desires, and just use read/write through MDS. The point here is to tell the client whether or not it should try pNFS if it can. Cheers Trond -- Trond Myklebust Linux NFS client maintainer NetApp Trond.Myklebust@xxxxxxxxxx www.netapp.com -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
