FUJITA Tomonori schrieb: > On Wed, 29 Oct 2008 12:26:58 +0100 > Tomasz Chmielewski <mangoo at wpkg.org> wrote: > >> Sometimes, I need to resize the device on the target. >> >> Technically, I do this as follows: >> >> lvextend -L+5G /dev/san14/blah1 >> tgt-admin --update tid=20 -v -f > > What does exactly 'tgt-admin --update tid=20 -v -f' do? Please explain > what tgtadm operations are performed. Please do so at all times (hint: > I don't understand how tgt-admin works). Basically, it disconnects all initiators, removes the target, and adds it again. Removing the lun and adding it again would be enough, as you also write below. > Well, unless you delete a logical unit and add it again, tgtd doesn't > know the new size. So probably, we need to a new interface to notify > tgtd of the change. > > >> However, the initiators won't see the change unless we "rescan" the >> device, i.e.: >> >> echo 1 > /sys/block/sdah/device/rescan > > Unless you use 2.6.28-rc kernel, it doesn't work, I think. It works for me with 2.6.18 kernels. >> This is a boring thing to do when we have more initiators connected to >> that target. >> Also, the initiators will likely have a different device used for that >> target (/sys/block/<DEVICE>/device/rescan), making the thing even more >> boring. >> >> >> Is it possible to send a reset/rescan to all initiators connected to a >> given target, which would trigger the initiator to rescan the device >> (and its size)? > > A scsi device can notify initiators of such event via UA (unit > attention), google "CAPACITY DATA HAS CHANGED". tgt has the mechanism > to handle UA so it's easy to support it. However, on the initiator > side, Linux doesn't detect such event automatically. I see. So let's just hope Linux will detect such events one day ;) -- Tomasz Chmielewski http://wpkg.org -- To unsubscribe from this list: send the line "unsubscribe stgt" in the body of a message to majordomo at vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html |