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For moving and resizing partitions on disk 1 (/dev/sda), the growpart command that we used on disk 2 (/dev/sdb) would in most cases not be the desired tool for this job as disk 1 (/dev/sda) has more than 1 partition.
GParted would probably be a more useful tool for achieving this:
https://gparted.org/display-doc.php%3Fname%3Dmoving-space-between-partitions
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