Persistent devices are those that retain data even after power to the device is cut off. Hard disk drives and solid state drives are common types of persistent storage. Ex: file, block.
RAM and cache are non-persistent and data is erased when power is off. Persistent is extremely useful and ensures data is not lost in cases of crash or reboot.
There are times when you need to resize persistent disks to handle data more efficiently. Note that you can only resize a persistent disk in order to increase its size. Reduction in size of a persistent disk is not possible.
Here are steps to add and resize your persistent disks.
- Add a persistent disk
You can create a standard persistent disk or an SSD persistent disk and attach it to an existing instance. You need to create and start a new instance if you do not have any instances.
Note that a maximum of 15 secondary non-boot persistent disks can be attached to store your files, applications, databases, and logs on separate volumes.
The permissions required for this task are:
- disks.create on the project to create a new disk.
- instances.attachDisk on VM instance.
- disks.use on the disk to attach.
You can create and attach a persistent disk in Google Cloud Platform Console
- Go to the VM instances page.
- Now click the name of the instance where you want to add a disk.
- At the top of instance details page, click Edit.
- Under Additional disks, click Add Item.
- In Name column for additional lists, click Select a disk drop down menu and select Create disk.
- You can configure properties for your new disk. Specify a name for the disk and select Blank disk
- Click Create to create the disk.
- At bottom of instance details page, click Save to apply your changes to the instance.
- Once you create and attach a new disk to an instance, you must format and mount the disk, thereby enabling the Operating system to use the available storage space.
- Resize a persistent disk
Resizing is required when your instances require more storage space. Note that you can resize your disks at any time, irrespective of the disk being attached to a running instance.
- Go to Disks page to see the list of persistent disks in your project.
- Now click on the name of the disk that you want to resize.
- At the top of disk details page, click Edit.
- In Size attribute, enter a new size for your disk.
- At the bottom of disk details page, click Save to apply your changes to the disk.
- Resizing the disk is not enough. You must also resize the file system for the Operating system to access additional space.
If there’s a partition table on your disk, such as a boot disk, you must grow the partition and resize the file system on that partition. If your persistent disk has only a file system and no partition table, you can only resize the file system.
Create a snapshot before you modify the file system on your persistent disk.
Data Recovery using Remo Recover software
If you experienced data loss during the resizing process, you can easily recover all the data using Remo Recover software.
The data recovery software can restore data from all kinds of hard drives, USB drives, memory cards, FireWire drives and so on.
Remo Recover restores data from lost, deleted, formatted and re-formatted partitions as well. If you re-installed your Operating system (OS) after data loss, do not worry. Remo Recover data recovery tool supports retrieval of data after re-installation of OS as well.
The software is compatible on all versions of Windows and Mac Operating systems.
Remo Recover also helps you recover data from systems where the hard disk is unknown, not initialized. The user interface is pretty simple and helps you recover data from uninitialized disk.
The software allows you to save the recovery session so that you do not have to scan from the beginning next time around.