CentOS - Jul 2018 - ssm vs. lvm: moving physical drives and volume group to another system

I did the following test:

###############################################
1.

Computer with Centos 7.5 installed on hard drive /dev/sda.

Added two hard drives to the computer: /dev/sdb and /dev/sdc.

Created a new logical volume in RAID-1 using RedHat System Storage Manager:

ssm create --fstype xfs -r 1 /dev/sdb /dev/sdc /mnt/data

Everything works.
/dev/lvm_pool/lvol001 is mounted to /mnt/data.
Files and folders can be copied/moved, read/written on /mnt/data.

###############################################

2.

I erased CentOS 7.5 from /dev/sda.
Wrote zeros to /dev/sda using dd.
Reinstalled CentOS 7 on /dev/sda.
Completed yum update - reboot - yum install system-storage-manager.

RedHat system storage manager listed all existing volumes on the computer:

[root at localhost]# ssm list

--------------------------------------------------------------------------------------
Volume              Pool   Volume size  FS     FS size       Free
Type    Mount point
--------------------------------------------------------------------------------------
/dev/cl/root        cl        65.00 GB  xfs   64.97 GB   63.67 GB
linear  /
/dev/cl/swap        cl         8.00 GB
linear
/dev/lvm_pool/lvol001 lvm_pool200.00 GB xfs  199.90 GB  184.53 GB
raid1   /mnt/data
/dev/cl/home        cl       200.00 GB  xfs  199.90 GB  199.87 GB
linear  /home
/dev/sda1                      4.00 GB  xfs    3.99 GB    3.86 GB
part    /boot
--------------------------------------------------------------------------------------
[/CODE]

So far, so good.  The new CentOS7 install can see the logical volume.

Mounted the volume:  ssm mount -t xfs /dev/lvm_pool/lvol001 /mnt/data
Works.
cd to /mnt/data and I can see the files left on the volume from the
previous tests.
Moving/copying/read/write -- works.

###################################################

3. Is it safe to assume when using RedHat System Storage Manager it's
not necessary to use the lvm commands (vgexport and vgimport) to move
two physical drives containing a logical volume in raid 1 from one
computer to another?

Thanks for your help and guidance.

Maybe not a good assumption afterall --

I can no longer boot using kernel 3.10.0-514 or 3.10.0-862.

boot.log shows:

Dependency failed for /mnt/data
Dependency failed for Local File Systems
Dependency failed for Mark the need to relabel after reboot.
Dependency failed for Migrate local SELinux policy changes from the
old store structure to the new structure.
Dependency failed for Relabel all filesystems, if necessary.


On Sat, Jul 14, 2018 at 12:55 PM Mike <1100100 at gmail.com>
wrote:
>
> I did the following test:
>
> ###############################################
> 1.
>
> Computer with Centos 7.5 installed on hard drive /dev/sda.
>
> Added two hard drives to the computer: /dev/sdb and /dev/sdc.
>
> Created a new logical volume in RAID-1 using RedHat System Storage Manager:
>
> ssm create --fstype xfs -r 1 /dev/sdb /dev/sdc /mnt/data
>
> Everything works.
> /dev/lvm_pool/lvol001 is mounted to /mnt/data.
> Files and folders can be copied/moved, read/written on /mnt/data.
>
> ###############################################
>
> 2.
>
> I erased CentOS 7.5 from /dev/sda.
> Wrote zeros to /dev/sda using dd.
> Reinstalled CentOS 7 on /dev/sda.
> Completed yum update - reboot - yum install system-storage-manager.
>
> RedHat system storage manager listed all existing volumes on the computer:
>
> [root at localhost]# ssm list
>
>
--------------------------------------------------------------------------------------
> Volume              Pool   Volume size  FS     FS size       Free
> Type    Mount point
>
--------------------------------------------------------------------------------------
> /dev/cl/root        cl        65.00 GB  xfs   64.97 GB   63.67 GB
> linear  /
> /dev/cl/swap        cl         8.00 GB
> linear
> /dev/lvm_pool/lvol001 lvm_pool200.00 GB xfs  199.90 GB  184.53 GB
> raid1   /mnt/data
> /dev/cl/home        cl       200.00 GB  xfs  199.90 GB  199.87 GB
> linear  /home
> /dev/sda1                      4.00 GB  xfs    3.99 GB    3.86 GB
> part    /boot
>
--------------------------------------------------------------------------------------
> [/CODE]
>
> So far, so good.  The new CentOS7 install can see the logical volume.
>
> Mounted the volume:  ssm mount -t xfs /dev/lvm_pool/lvol001 /mnt/data
> Works.
> cd to /mnt/data and I can see the files left on the volume from the
> previous tests.
> Moving/copying/read/write -- works.
>
> ###################################################
>
> 3. Is it safe to assume when using RedHat System Storage Manager it's
> not necessary to use the lvm commands (vgexport and vgimport) to move
> two physical drives containing a logical volume in raid 1 from one
> computer to another?
>
> Thanks for your help and guidance.

When I change /etc/fstab from /dev/mapper/lvol001 to
/dev/lvm_pool/lvol001, kernel 3.10.0-514 will boot.

Kernel 3.10.0-862 hangs and will not boot.
On Sat, Jul 14, 2018 at 1:20 PM Mike <1100100 at gmail.com>
wrote:
>
> Maybe not a good assumption afterall --
>
> I can no longer boot using kernel 3.10.0-514 or 3.10.0-862.
>
> boot.log shows:
>
> Dependency failed for /mnt/data
> Dependency failed for Local File Systems
> Dependency failed for Mark the need to relabel after reboot.
> Dependency failed for Migrate local SELinux policy changes from the
> old store structure to the new structure.
> Dependency failed for Relabel all filesystems, if necessary.
>
>
> On Sat, Jul 14, 2018 at 12:55 PM Mike <1100100 at gmail.com> wrote:
> >
> > I did the following test:
> >
> > ###############################################
> > 1.
> >
> > Computer with Centos 7.5 installed on hard drive /dev/sda.
> >
> > Added two hard drives to the computer: /dev/sdb and /dev/sdc.
> >
> > Created a new logical volume in RAID-1 using RedHat System Storage
Manager:
> >
> > ssm create --fstype xfs -r 1 /dev/sdb /dev/sdc /mnt/data
> >
> > Everything works.
> > /dev/lvm_pool/lvol001 is mounted to /mnt/data.
> > Files and folders can be copied/moved, read/written on /mnt/data.
> >
> > ###############################################
> >
> > 2.
> >
> > I erased CentOS 7.5 from /dev/sda.
> > Wrote zeros to /dev/sda using dd.
> > Reinstalled CentOS 7 on /dev/sda.
> > Completed yum update - reboot - yum install system-storage-manager.
> >
> > RedHat system storage manager listed all existing volumes on the
computer:
> >
> > [root at localhost]# ssm list
> >
> >
--------------------------------------------------------------------------------------
> > Volume              Pool   Volume size  FS     FS size       Free
> > Type    Mount point
> >
--------------------------------------------------------------------------------------
> > /dev/cl/root        cl        65.00 GB  xfs   64.97 GB   63.67 GB
> > linear  /
> > /dev/cl/swap        cl         8.00 GB
> > linear
> > /dev/lvm_pool/lvol001 lvm_pool200.00 GB xfs  199.90 GB  184.53 GB
> > raid1   /mnt/data
> > /dev/cl/home        cl       200.00 GB  xfs  199.90 GB  199.87 GB
> > linear  /home
> > /dev/sda1                      4.00 GB  xfs    3.99 GB    3.86 GB
> > part    /boot
> >
--------------------------------------------------------------------------------------
> > [/CODE]
> >
> > So far, so good.  The new CentOS7 install can see the logical volume.
> >
> > Mounted the volume:  ssm mount -t xfs /dev/lvm_pool/lvol001 /mnt/data
> > Works.
> > cd to /mnt/data and I can see the files left on the volume from the
> > previous tests.
> > Moving/copying/read/write -- works.
> >
> > ###################################################
> >
> > 3. Is it safe to assume when using RedHat System Storage Manager
it's
> > not necessary to use the lvm commands (vgexport and vgimport) to move
> > two physical drives containing a logical volume in raid 1 from one
> > computer to another?
> >
> > Thanks for your help and guidance.