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Re: [Xen-users] tap:aio not working...

To: Nick Couchman <Nick.Couchman@xxxxxxxxx>
Subject: Re: [Xen-users] tap:aio not working...
From: Kevin Wolf <kwolf@xxxxxxx>
Date: Mon, 05 May 2008 14:12:41 +0200
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Nick Couchman schrieb:
xen02:~ # lsmod | grep -i tap
blktap                121604  2 [permanent]
xenbus_be               8832  3 netbk,blkbk,blktap
xen02:~ # ps -ef | grep blk
root      7060     1  0 Apr28 ?        00:00:00 blktapctrl
root     31500 31466  0 06:59 pts/0    00:00:00 grep blk

Clearly the blktap module is loaded (is there another one I need??) and the control daemon is running.

Looks right so far.

The only messages that I get with BLKTAP or TAPDISK occur when I manually do an "xm block-attach" to dom0 to test out the tap:aio method.

So if you try to block-attach the image to Dom0 it works and the problem is only with DomU? Unfortunately I currently don't have a machine installed with SP1 here, it's all the SP2 RCs now.

Looking at my own logfiles I found that I get this "blkback: ring-ref" lines only when I use file. With blktap it doesn't show up at all. So the information that you wanted blktap might have been lost somewhere in the middle of the domain startup. This would also explain the missing BLKTAP and TAPDISK lines.


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