It works. Thanks a lot. >-----Original Message----- >From: Kevin Corry [mailto:kevcorry@xxxxxxxxxx] >Sent: 2004年6月25日 20:48 >To: dm-devel@xxxxxxxxxx >Cc: Ling, Xiaofeng >Subject: Re: [dm-devel] how to create /dev/mapper/control? > >On Thursday 24 June 2004 4:53 am, Ling, Xiaofeng wrote: >> I download and install device-mapper, >> but when I run dmsetup info, it says /dev/mapper/control open failed. >> So how should I create the device node? what major & minor? >> I tried 253,0, still fail. > >In the device-mapper source package, there's a script called >scripts/devmap_mknod.sh that you can run from your boot-scripts to >create /dev/mapper/control each time you boot. > >In practice, I've always seen /dev/mapper/control with >dev-number 10:63. But >this isn't guaranteed. The control node is registered with the "misc" >character driver, and simply asks for the first available >minor number under >that driver. This means you need to first grep /proc/devices >for "misc" to >get the major number, then grep /proc/misc for "device-mapper" >to get the >minor number. This is basically what the above script does. > >-- >Kevin Corry >kevcorry@xxxxxxxxxx >http://evms.sourceforge.net/ > >