Difference between revisions of "Parted: Basic operations"

From Define Wiki
Jump to navigation Jump to search
(Created page with "== Launch parted and select disk == Launch <code>parted</code> by typing parted from the bash prompt: <syntaxhighlight> [root@localhost ~]# parted GNU Parted 2.1 Using /dev/sda Welcome ...")
 
 
(One intermediate revision by one other user not shown)
Line 35: Line 35:
 
(parted) mkpart primary 0.00TB 3.00TB
 
(parted) mkpart primary 0.00TB 3.00TB
 
</syntaxhighlight>
 
</syntaxhighlight>
The syntax for the above is <code>mkpart <start position> <end position></code>
+
The syntax for the above is <code>mkpart <label> <start position> <end position></code>
 +
 
 +
== Display partition table ==
 +
<syntaxhighlight>
 +
(parted) print
 +
Model: ATA ST33000651AS (scsi)
 +
Disk /dev/sdb: 3.00TB
 +
Sector size (logical/physical): 512B/512B
 +
Partition Table: gpt
 +
Number  Start  End    Size    File system  Name    Flags
 +
1      0.00TB  3.00TB  3.00TB  ext4        primary
 +
</syntaxhighlight>
 +
 
 +
== Exit parted ==
 +
<syntaxhighlight>
 +
(parted) quit
 +
</syntaxhighlight>
 +
 
 +
== Partition Alignment ==
 +
* Ensure the partitions are optimally aligned for performance tests
 +
* Being lazy will result in misaligned partitions regardless of what numbers you use
 +
<syntaxhighlight>
 +
(parted) mklabel gpt
 +
(parted) mkpart primary 0 100%
 +
Warning: The resulting partition is not properly aligned for best performance.
 +
Ignore/Cancel?
 +
</syntaxhighlight>
 +
 
 +
Use the following (in this example we are creating 3 partition on the volume)
 +
<syntaxhighlight>
 +
[root@localhost ~]# parted -a optimal /dev/sda
 +
GNU Parted 2.1
 +
Using /dev/sda
 +
Welcome to GNU Parted! Type 'help' to view a list of commands.
 +
(parted) unit % mkpart primary 0% 33%                                   
 +
(parted) unit % mkpart primary 33% 66%                                   
 +
(parted) unit % mkpart primary 66% 100%                                 
 +
(parted) print                                                           
 +
Model: LSI MR9261-8i (scsi)
 +
Disk /dev/sda: 100%
 +
Sector size (logical/physical): 512B/512B
 +
Partition Table: gpt
 +
 
 +
Number  Start  End    Size  File system  Name    Flags
 +
1      0.00%  33.0%  33.0%              primary
 +
2      33.0%  66.0%  33.0%              primary
 +
3      66.0%  100%  34.0%              primary
 +
 
 +
(parted) align-check optimal 1                                           
 +
(parted) align-check optimal 2                                           
 +
(parted) align-check optimal 3             
 +
</syntaxhighlight>

Latest revision as of 14:05, 19 October 2014

Launch parted and select disk

Launch parted by typing parted from the bash prompt:

[root@localhost ~]# parted
GNU Parted 2.1
Using /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted)

Select disk by entering the device name, eg. /dev/sdb:

(parted) select /dev/sdb

giving the following output:

GNU Parted 2.3
Using /dev/sdb
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted)

Changing the partition table to GPT to support partitions >2TB

(parted) mklabel gpt
Warning: The existing disk label on /dev/sdb will be destroyed and all data on this disk will be lost. Do you want to continue?
Yes/No? yes
(parted)

Set units to TB and create partition

(parted) unit TB
(parted) mkpart primary 0.00TB 3.00TB

The syntax for the above is mkpart <label> <start position> <end position>

Display partition table

(parted) print
Model: ATA ST33000651AS (scsi)
Disk /dev/sdb: 3.00TB
Sector size (logical/physical): 512B/512B
Partition Table: gpt
Number  Start   End     Size    File system  Name     Flags
 1      0.00TB  3.00TB  3.00TB  ext4         primary

Exit parted

(parted) quit

Partition Alignment

  • Ensure the partitions are optimally aligned for performance tests
  • Being lazy will result in misaligned partitions regardless of what numbers you use
(parted) mklabel gpt
(parted) mkpart primary 0 100%
Warning: The resulting partition is not properly aligned for best performance.
Ignore/Cancel?

Use the following (in this example we are creating 3 partition on the volume)

[root@localhost ~]# parted -a optimal /dev/sda
GNU Parted 2.1
Using /dev/sda
Welcome to GNU Parted! Type 'help' to view a list of commands.
(parted) unit % mkpart primary 0% 33%                                     
(parted) unit % mkpart primary 33% 66%                                    
(parted) unit % mkpart primary 66% 100%                                   
(parted) print                                                            
Model: LSI MR9261-8i (scsi)
Disk /dev/sda: 100%
Sector size (logical/physical): 512B/512B
Partition Table: gpt

Number  Start  End    Size   File system  Name     Flags
 1      0.00%  33.0%  33.0%               primary
 2      33.0%  66.0%  33.0%               primary
 3      66.0%  100%   34.0%               primary

(parted) align-check optimal 1                                            
(parted) align-check optimal 2                                            
(parted) align-check optimal 3