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On Tuesday, May 06, 2014 05:34:52 PM Walter Dnes wrote: |
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> On Tue, May 06, 2014 at 08:45:01PM +0200, J. Roeleveld wrote |
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> |
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> > On Tuesday, May 06, 2014 02:31:08 PM Walter Dnes wrote: |
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> > > I'm trying to set up USB-key-encryption for use with a laptop. I'm |
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> > > |
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> > > running mdev instead of udev on the laptop, so lvm doesn't work. |
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> > |
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> > I find this strange, as LVM can manage the /dev-entries directly. |
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> > On my systems, this is necessary as udev regularly fails to properly |
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> > handle |
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> > these entries. |
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> > |
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> > Eg. the following setting: " verify_udev_operations = 1 " |
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> > There are other options for udev documented in /etc/lvm/lvm.conf. |
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> |
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> Unfortunately, mdev != udev. People running RAID have problems too. |
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I know it isn't. I just find it strange that LVM can't work without udev when I |
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see options which configure the LVM-tools to either double-check udevs actions |
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or even completely bypass udev: |
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*** |
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|
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# Set to 0 to disable udev synchronisation (if compiled into the |
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binaries). |
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# Processes will not wait for notification from udev. |
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# They will continue irrespective of any possible udev processing |
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# in the background. You should only use this if udev is not running |
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# or has rules that ignore the devices LVM2 creates. |
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# The command line argument --nodevsync takes precedence over this |
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setting. |
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# If set to 1 when udev is not running, and there are LVM2 processes |
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# waiting for udev, run 'dmsetup udevcomplete_all' manually to wake them |
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up. |
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udev_sync = 1 |
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|
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# Set to 0 to disable the udev rules installed by LVM2 (if built with |
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# --enable-udev_rules). LVM2 will then manage the /dev nodes and symlinks |
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# for active logical volumes directly itself. |
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# N.B. Manual intervention may be required if this setting is changed |
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# while any logical volumes are active. |
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udev_rules = 1 |
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|
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# Set to 1 for LVM2 to verify operations performed by udev. This turns on |
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# additional checks (and if necessary, repairs) on entries in the device |
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# directory after udev has completed processing its events. |
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# Useful for diagnosing problems with LVM2/udev interactions. |
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verify_udev_operations = 1 |
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|
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|
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*** |
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|
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> > I believe " cryptsetup " does not use the LVM tools. But has a new device |
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> > created by the kernel directly, which should be picked up by a device |
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> > manager directly. |
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> |
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> But cryptsetup pulls in lvm2 as a dependancy... |
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> |
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> [d531][waltdnes][~] emerge -pv cryptsetup |
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> |
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> These are the packages that would be merged, in order: |
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> |
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> Calculating dependencies... done! |
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> [ebuild N ] sys-fs/lvm2-2.02.103 USE="readline (-clvm) (-cman) -lvm1 |
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> -lvm2create_initrd (-selinux) -static -static-libs -thin -udev" 1,313 kB |
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> [ebuild N ] sys-fs/cryptsetup-1.6.2 USE="openssl -gcrypt -kernel |
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> -nettle -nls -python -reencrypt -static -static-libs -udev -urandom" |
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> PYTHON_SINGLE_TARGET="python2_7 -python2_6" PYTHON_TARGETS="python2_7 |
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> -python2_6" 1,162 kB |
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You need it for the device-mapper stuff. That might also listen to the above |
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setting in /etc/lvm/lvm.conf. |
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Can you try setting the above one to " 0" and re-test? |
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I don't have any machine with mdev to test myself. |
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Also, the following page seems to indicate cryptsetup, LVM and mdev do work |
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together: |
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http://jootamam.net/howto-basic-cryptsetup.htm |
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This works inside an initramfs and I don't see a reason why it can't work |
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outside of the initramfs. |
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-- |
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