On Thu, 2005-05-12 at 14:52 -0400, James Bottomley wrote: > On Wed, 2005-05-11 at 00:00 +0200, Guennadi Liakhovetski wrote: > > A follow up question - I recently used nbd to access a CD-ROM. It worked > > nice, but, I had to read in 7 CDs, so, each time I had to replace a CD, I > > had to stop the client, the server, then replace the CD, re-start the > > server, re-start the client... I thought about extending NBD to (better) > > support removable media, but then you start thinking about all those > > features that your local block device has that don't get exported over > > NBD... > > That's correct; NBD is basically just a remote data pipe type block > device. It doesn't understand arbitrary packet commands. > > > Now, my understanding (sorry, without looking at any docs - yet) is, that > > iSCSI is (or at least should be) free from these limitations. So, does it > > make any sense at all extending NBD or just switch to iSCSI? Should NBD be > > just kept simple as it is or would it be completely superseeded by iSCSI, > > or is there still something that NBD does that iSCSI wouldn't (easily) do? > > Caveat: I've done quite a bit of work on nbd, so I'm biased. However, > for what it does, nbd is extremely small, simple and efficient, so I > think we'd want a hole in our head to replace it with something as > complex and bloated as iSCSI---remember we'd need both a target and an > initiator to do what nbd does today. oh, please! don't compare nbd and iSCSI this way... iSCSI is an emerging SAN technology, and the only technology to compare is FC. > However, there is room for improvement in nbd, notably the handling of > packet commands, which looks to be eminently doable in the current > infrastructure (this would basically make nbd a replicator for the linux > block system, and would probably necessitate some client side changes to > achieve). If you have any thoughts in this direction, you could drop an > email to the maintainer. > > James > > > - > : send the line "unsubscribe linux-scsi" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html - : send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
