On 01/06/12 00:12, .. ink .. wrote: > I read the announcement of 1.4.3 and decided to do a simple test on > opening multiple mappers on the same device and this is what i found > out: > > test using cryptsetup 1.4.3 > > [root@mtz ink]# echo -n xxx | cryptsetup create zzz xxx > [root@mtz ink]# echo -n xxx | cryptsetup create zzz xxx > Device zzz already exists. > [root@mtz ink]# echo -n xxx | cryptsetup create yyy xxx > > [root@mtz ink]# ls -l /dev/mapper/ > total 0 > crw------- 1 root root 10, 236 May 29 14:46 control > lrwxrwxrwx 1 root root 7 May 31 18:01 yyy -> ../dm-1 > lrwxrwxrwx 1 root root 7 May 31 18:01 zzz -> ../dm-0 > > [root@mtz ink]# zuluCrypt-cli -P -d /dev/mapper/zzz > /home/ink/xxx > [root@mtz ink]# zuluCrypt-cli -P -d /dev/mapper/yyy > /home/ink/xxx > [root@mtz ink]# > > It looks like by default, cryptsetup does not allow opening more than > one mapper on the same device bu it only checks the mapper name, not > the device behind the mapper and hence it allows opening of multiple > mappers on the same device as long as they use a different mapper > name. > > The same behavior is there in luks based volume > > Also,shouldnt the error say mapper name since the check is on the > mapper,not the device behind the mapper. > _______________________________________________ > dm-crypt mailing list > dm-crypt@xxxxxxxx > http://www.saout.de/mailman/listinfo/dm-crypt The default behaviour is to forbid it. As Milan said you need --shared flag to "avoid" it. Please check note issue 123 and Milan answer about the "safety" of --shared use. You shall create linear mappings under raw cryptsetup created devices and work under this linear mappings and not with the cryptsetup raw created one when using --shared flag. _______________________________________________ dm-crypt mailing list dm-crypt@xxxxxxxx http://www.saout.de/mailman/listinfo/dm-crypt
