How can I check and change the partition table type?

Question

I have an universal React application using Redux, React-routerV4, MySQL and Sequelize. I am trying to protect some routes, and I'm using Passport for that, like in this tutorial: https://hptechblogs.com/using-json-web-token-react/

Usually with JWT storing on web browser is recommended, because you don't have to make request to the DB everytime you load a route. But in the case of an Application with SSR this is not useful, because the components loaded by the server can't access LocalStorage or SessionStorage.

I am thinking if storing the token in a cookie is better in the case of universal applications… Any idea?

Thanks!

Solution

What is a partition table? How is it related to Windows 8?

In addition to general partitioning, it should be noted that information about partitions are stored in a partition table on the hard disk.

The whole topic didn't receive much attention because DOS/Windows computers – where one would install Linux onto – just had one choice for almost three decades. ^{(MBR was introduced in 1983.)} Until Windows 8 finally replaced the long overdue and outdated BIOS/MBR subsystem combination with UEFI/GPT. ^{(Comparison of GPT and MBR on the Arch Wiki.)}

While GPT is the name for the new format, there is some confusion about how to name the old one as MBR previously described the bootloader code that is stored along the partition information in the partition table.

How do I check and change the partition table?

Read these instructions carefully before you start!

Also note that you can convert partition tables: How can I change/convert a Ubuntu MBR drive to a GPT, and make Ubuntu boot from EFI?

1. GUI-method - Using GParted

   To find out what partition table type the selected drive has select View > Device Information from the menu.

   

   Select the disk of which you want to change the partition, then select Device > Create Partition Table from the menu.

   

   If you get a warning that the device contains active partitions, unmount these. Note that you cannot unmount partitions of your currently running operating system. You will then see the window below, where you can choose the partition table type. msdos is what GParted calls the old format, gpt the newer one. All the others for other operating systems or architectures.

   Please also note the warning message. Creating a new partition table will discard all information about existing partitions on the disk. It will not overwrite data on the partitions, but you still don't want to have to dig through and restore data afterwards. Therefore consider the old partitions gone and all data lost after you created the new partition table and backup your data before doing so.

   

2. CLI-method - Using parted

   To display partition table information run:

   sudo parted --list
   

   To create a new partition table run:

   # This is a destructive action that will destroy all data on the partitions of the device
   sudo parted device mklabel label-type
   

   device should be replaced with the device name (e.g. /dev/sdb) and label-type with msdos or gpt.

   You can also run parted interactively by just running sudo parted. More details in the manpage.

Comments

[Alaa Ali]

Great into, but 1) you can still expand on the What is a partition table part, 2) it's not clear (at least to new/non-techy/not-into-harddisks people) if doing these steps will completely wipe out the hard disk, or just change to GPT and not harm partitions, 3) I think it's always best practice to put "please backup all your data" in answers involving partitions, and 4) why don't you just post your answer to How can I change/convert a Ubuntu MBR drive to a GPT, and make Ubuntu boot from EFI? instead? Your question might be considered a duplicate.

[Csabi Vidó]

@AlaaAli I want to keep this as brief as possible. The first sentence could be phrased better, but I don't want to go down to engineering level (I don't think there is much more to say about partition tables than engineering). 2 & 3) Information added. 4) The site seems to have a problem with overly long, monolithic and redundant answers while users are not able to find the information they are looking for. Would you find it there? The question about conversion should at best only be about conversion for the readers sake and not mix with (data) destructive answers. I appreciate your input. :)

[Fabby]

and +1 here too! ;-) Drop by in chat sometime so I don't have to leave comments here...

[Admin]

isn't it aplicable for an existing installation without data lose ?