Help with HDD issue iMac 2013 Late 2013

[photogramps]

I just acquired a late 2013 iMac 21.5 - 2.7 GHz Quad-Core Intel Core i5 - first thing I did was download a macOS Catalina Installer and did a clean install of Catalina, which went fine and I started with a fresh iMac.

It has a 1TB HDD fitted but there is an issue with trying to use Time Machine to backup.
Initiating a backup brings the error:-

Time Machine - Could Not Backup
Two of the disks have the same name, rename one of the disks named APPLE HDD HTSXXXXXXXX Media - Data

When I view About This Mac > Storage I see the drive shown as 1TB SATA Disk with two divisions:-

• APPLE HDD HTSXXXXXXXX Media
• APPLE HDD HTSXXXXXXXX Media - Data

However, when I view in Disk Utility I see:-

• APPLE HDD HTSXXXXXXXX Media (Shows a Finder icon) ... Used 11.24GB - Other Volumes 13.25GB - Free 975.37GB
• APPLE HDD HTSXXXXXXXX Media - Data (Shows a Home icon) ... Used 8.09GB - Other Volumes 16.36GB - Free 975.37GB
• APPLE HDD HTSXXXXXXXX Media - Data (No icon shown) ... Used 1MB - Other Volumes 24.49 - Free 975.37GB

Now I guess I could just go ahead and rename one of the disks but what would that do?
Why are there three disks showing in Disk Utility and only two in About This Mac?
I don't want to mess anything up here so would welcome any input please.

Edit: diskutil List shows:-

/dev/disk0 (internal, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *1.0 TB disk0
1: EFI EFI 209.7 MB disk0s1
2: Apple_APFS Container disk1 999.9 GB disk0s2

/dev/disk1 (synthesized):
#: TYPE NAME SIZE IDENTIFIER
0: APFS Container Scheme - +999.9 GB disk1
Physical Store disk0s2
1: APFS Volume APPLE HDD HTSXXXXXXX... 1.0 MB disk1s1
2: APFS Volume Preboot 80.9 MB disk1s2
3: APFS Volume Recovery 528.8 MB disk1s3
4: APFS Volume VM 4.3 GB disk1s4
5: APFS Volume APPLE HDD HTSXXXXXXX... 8.2 GB disk1s5
6: APFS Volume APPLE HDD HTSXXXXXXX... 11.2 GB disk1s6

/dev/disk3 (external, physical):
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *320.1 GB disk3
1: EFI EFI 209.7 MB disk3s1
2: Apple_HFS Backup 319.7 GB disk3s2

 

[casperes1996]

When you did a clean install of Catalina how did you wipe the drive? In Disk utility did you select the View->All Devices option? By default Disk Utility only shows volumes, not disks. You need to set it to also show disks and erase the disk to do a complete clean install, otherwise you might have a left-over volume from the prior installation

 

[photogramps]

When you did a clean install of Catalina how did you wipe the drive? In Disk utility did you select the View->All Devices option? By default Disk Utility only shows volumes, not disks. You need to set it to also show disks and erase the disk to do a complete clean install, otherwise you might have a left-over volume from the prior installation

Thanks for responding.
I suspect that it was just default, I didn't think to change anything before doing the clean install.
Is there a way around it or does it mean I have to lose everything I've done up to now and do the clean install again?

 

[casperes1996]

Thanks for responding.
I suspect that it was just default, I didn't think to change anything before doing the clean install.
Is there a way around it or does it mean I have to lose everything I've done up to now and do the clean install again?

It would probably be easier to redo the install, but alternatively you can probably just remove the extra volume from Disk Utility; Though I advice first making sure there's nothing on there you want to keep. In Disk Utility when the volume is selected, if it's greyed out there should be a mount option to get it planted on the desktop to browse through. Then when you've checked it, unmount it and there should be a "-" button to remove it

 

[photogramps]

It would probably be easier to redo the install, but alternatively you can probably just remove the extra volume from Disk Utility; Though I advice first making sure there's nothing on there you want to keep. In Disk Utility when the volume is selected, if it's greyed out there should be a mount option to get it planted on the desktop to browse through. Then when you've checked it, unmount it and there should be a "-" button to remove it

Thank you I'll check that out.

 

[photogramps]

Well doing a 'proper' wipe of the drive did the trick, thanks again for the help. 👍

 

[casperes1996]

Well doing a 'proper' wipe of the drive did the trick, thanks again for the help. 👍

Cheers; Sorry you had to go through an inconvenience, but glad it's sorted