[parted-devel] Parted 3.1.90 Testing with DMRAID on Debian 8 Jessie	(Testing)
    Curtis Gedak 
    gedakc at gmail.com
       
    Sat Jul 26 17:35:51 UTC 2014
    
    
  
Thank you Phillip for the tip about creating an Intel Software RAID in a 
Virtual Machine.  :-)
Following are my DMRAID test results on a Debian Testing Virtual Machine.
Test Setup:
   Debian 8 Jessie Testing (updated to latest packages)
   Parted 3.1.90
   GParted 0.19.1 configured with: --enable-libparted-dmraid
                              and  --enable-online-resize
1)  Create two 1 GB disks in Virtual Machine (sdc and sdd)
2)  Create Intel Software RAID
# dmraid -f isw -C MyRaid1 --type 1 --disks /dev/sdc,/dev/sdd
3)  Reboot
4)  List dmraid device paths
# ls -l /dev/mapper
total 0
crw------- 1 root root  10, 236 Jul 26 10:57 control
brw-rw---- 1 root disk 254,   0 Jul 26 10:57 isw_ebcdedbibh_MyRaid1
5)  Run GParted, create msdos partition table, create 128 MiB
     ext4 partition, and apply operations.
     SUCCESS!
     GParted works correctly with newly created
     isw_ebcdedbibh_MyRaid1p1 partition and reads the file system usage
     details.
6)  List dmraid device paths
# ls -l /dev/mapper
total 0
crw------- 1 root root  10, 236 Jul 26 10:57 control
brw-rw---- 1 root disk 254,   0 Jul 26 10:59 isw_ebcdedbibh_MyRaid1
lrwxrwxrwx 1 root root        7 Jul 26 11:00 isw_ebcdedbibh_MyRaid1p1 -> 
../dm-1
# ls -l /dev/dm-*
brw-rw---- 1 root disk 254, 0 Jul 26 10:57 /dev/dm-0
brw-rw---- 1 root disk 254, 1 Jul 26 11:00 /dev/dm-1
7)  Reboot
8)  List dmraid device paths
# ls -l /dev/mapper
total 0
crw------- 1 root root  10, 236 Jul 26 11:02 control
brw-rw---- 1 root disk 254,   0 Jul 26 11:02 isw_ebcdedbibh_MyRaid1
brw-rw---- 1 root disk 254,   1 Jul 26 11:02 isw_ebcdedbibh_MyRaid11
     NOTE:  Missing 'p' in partition device path.
9) Start GParted.
     GParted cannot read partition details.
     Suspected reason:
     isw_ebcdedbibh_MyRaid1p1  <-- what libparted expects
     isw_ebcdedbibh_MyRaid11   <-- what dmraid actually created
To summarize, parted-3.1.90 fixes a previous problem with creating the
partition device entry in /dev/mapper.
However, there still appears to be a disconnect between the naming
method usedFollowing are my DMRAID test results on a Debian Testing 
Virtual Machine.
Test Setup:
   Debian 8 Jessie Testing (updated to latest packages)
   Parted 3.1.90
   GParted 0.19.1 configured with: --enable-libparted-dmraid
                              and  --enable-online-resize
1)  Create two 1 GB disks in Virtual Machine (sdc and sdd)
2)  Create Intel Software RAID
# dmraid -f isw -C MyRaid1 --type 1 --disks /dev/sdc,/dev/sdd
3)  Reboot
4)  List dmraid device paths
# ls -l /dev/mapper
total 0
crw------- 1 root root  10, 236 Jul 26 10:57 control
brw-rw---- 1 root disk 254,   0 Jul 26 10:57 isw_ebcdedbibh_MyRaid1
5)  Run GParted, create msdos partition table, create 128 MiB
     ext4 partition, and apply operations.
     SUCCESS!
     GParted works correctly with newly created
     isw_ebcdedbibh_MyRaid1p1 partition and reads the file system usage
     details.
6)  List dmraid device paths
# ls -l /dev/mapper
total 0
crw------- 1 root root  10, 236 Jul 26 10:57 control
brw-rw---- 1 root disk 254,   0 Jul 26 10:59 isw_ebcdedbibh_MyRaid1
lrwxrwxrwx 1 root root        7 Jul 26 11:00 isw_ebcdedbibh_MyRaid1p1 -> 
../dm-1
# ls -l /dev/dm-*
brw-rw---- 1 root disk 254, 0 Jul 26 10:57 /dev/dm-0
brw-rw---- 1 root disk 254, 1 Jul 26 11:00 /dev/dm-1
7)  Reboot
8)  List dmraid device paths
# ls -l /dev/mapper
total 0
crw------- 1 root root  10, 236 Jul 26 11:02 control
brw-rw---- 1 root disk 254,   0 Jul 26 11:02 isw_ebcdedbibh_MyRaid1
brw-rw---- 1 root disk 254,   1 Jul 26 11:02 isw_ebcdedbibh_MyRaid11
     NOTE:  Missing 'p' in partition device path.
9) Start GParted.
     GParted cannot read partition details.
     Suspected reason:
     isw_ebcdedbibh_MyRaid1p1  <-- what libparted expects
     isw_ebcdedbibh_MyRaid11   <-- what dmraid actually created
To summarize, parted-3.1.90 fixes a previous problem with creating the
partition device entry in /dev/mapper.
However, there still appears to be a disconnect between the naming
method used by the dmraid package, versus the normal naming standard
used by libparted.
Current dmraid package partition naming method:
   Always append partition number to device name.
Parted 3.1.90 normal partition naming standard:
   If device name ends in a letter
     then append partition number to device name
   Else if device name ends in a number
     then append 'p' plus the partition number to device name
 From my experience the naming standard used by parted 3.1.90 is the
commonly used naming standard by GNU/Linux.  The dmraid partition
naming method is non-standard.
Please let me know if you require additional dmraid testing.
Regards,
Curtis
  by the dmraid package, versus the normal naming standard
used by libparted.
Current dmraid package partition naming method:
   Always append partition number to device name.
Parted 3.1.90 normal partition naming standard:
   If device name ends in a letter
     then append partition number to device name
   Else if device name ends in a number
     then append 'p' plus the partition number to device name
 From my experience the naming standard used by parted 3.1.90 is the
commonly used naming standard by GNU/Linux.  The dmraid partition
naming method is non-standard.
Please let me know if you require additional dmraid testing.
Regards,
Curtis
    
    
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