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time machine share not working

Hi,

I've always used a USB Hard Disk for Time Machine on my iMac 21.5" 2017 without issues. Now I'm also using a MacBook Pro 13" 2017 and I wanted to use the same USB drive to do the backup, so I created a folder on the USB drive and set it up as a shared Time Machine destination. My Macbook can write and read on the destination, but when I select the drive on the Time Machine preferences it says that it doesn't support the required function. Any help? Both are with latest Catalina 10.15.6

iMac 21.5″ 4K, macOS 10.15

Posted on Aug 11, 2020 12:22 AM

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Question marked as Best reply

Posted on Aug 14, 2020 6:04 AM

Solved!


I found that /Library/Preferences/SystemConfiguration/com.apple.smb.server has an incorrect value at ProtocolVersionMap.

This value can be 1 (SMB 1), 2 (SMB 2) or 4 (SMB 3). Mine was set on 2, so it was forcing SMB 2 rejecting all SMB 3 requests.


Changed the value to 4 and rebooting solved everything.

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5 replies

Aug 13, 2020 7:25 AM in response to Johnny Ego

Hi Johnny Ego,


We're glad you're reaching out through Apple Support Communities for help with your Time Machine backup. We're glad to help!


If you've created a folder on the external drive that exists in the same partition as the Time Machine backups for your other Mac, it would explain the message you're seeing. You'll want to create a separate partition for the backup of your MacBook Pro.


Here's a great Knowledge Base article with more information:


Types of disks you can use with Time Machine on Mac


To create a new partition using the available storage space on your external drive, follow this guide:


Partition a physical disk in Disk Utility on Mac


Have a great day!

time machine share not working

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