{kb-symptom}
Message received:
{code}
Can not back up /dev/sdb partition since /dev/sda partition has the same identifier.
{code}
{kb-cause}
{color:blue}fdisk{color} does not correctly write the partition ID when partitioning a disk.
{info:title=Note}CDP requires all partitions to have a unique ID even if the partition has not been selected as a Device in the Disk Safe for replication.
{info}
{kb-resolution}
A unique partition ID must be created.
{note:title=Warning}This is a dangerous operation. Make sure all data has been backed up *before* changing any partition information on your disk. A failure in changing partition data can make the machine unbootable.
{note}
{info:title=Note}Some operating systems such as RHEL 5 and Centos use an older version of fdisk contained in the util-linux package, which does not include the ability to change the partition identifier. The util-linux package has been replaced in more updated operating systems with the util-linux-ng package. In these cases you would need to manually upgrade the fdisk utility.
{info}
{code}
# fdisk /dev/sdb (enter the correct disk identifier assigned by Linux)
fdisk> x (for advanced)
fdisk> i (for create partition id)
(Enter in an arbitrary number)
fdisk> w (to save and exit)
{code}
{kb-related-articles}
Message received:
{code}
Can not back up /dev/sdb partition since /dev/sda partition has the same identifier.
{code}
{kb-cause}
{color:blue}fdisk{color} does not correctly write the partition ID when partitioning a disk.
{info:title=Note}CDP requires all partitions to have a unique ID even if the partition has not been selected as a Device in the Disk Safe for replication.
{info}
{kb-resolution}
A unique partition ID must be created.
{note:title=Warning}This is a dangerous operation. Make sure all data has been backed up *before* changing any partition information on your disk. A failure in changing partition data can make the machine unbootable.
{note}
{info:title=Note}Some operating systems such as RHEL 5 and Centos use an older version of fdisk contained in the util-linux package, which does not include the ability to change the partition identifier. The util-linux package has been replaced in more updated operating systems with the util-linux-ng package. In these cases you would need to manually upgrade the fdisk utility.
{info}
{code}
# fdisk /dev/sdb (enter the correct disk identifier assigned by Linux)
fdisk> x (for advanced)
fdisk> i (for create partition id)
(Enter in an arbitrary number)
fdisk> w (to save and exit)
{code}
{kb-related-articles}