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macmesser

macrumors 6502a
Original poster
Aug 13, 2012
921
198
Long Island, NY USA
On my home LAN, an OS 10.13.6 desktop Mac shares external disk for TIME MACHINE with a laptop but Macbook Pro client can't connect, although shared drive is selectable. Desktop appears in the MacBook Pro Finder. If it were a problem with the LAN would the desktop even be visible?
 
Permissions?

If the desktop Mac has the drive shared, any compute on the network will see it in Finder\Windows Network Neighborhood. The first time you connect, you should be prompted for a user name and password. Use an account that exists on the Desktop Mac and which has been given permissions to read and write to the disk. If you previously entered an incorrect account, you should see a Connect As button in Finder, enter the correct account info.

You can select the option to save the credentials (in Keychain). This makes it easier to connect next time, but if entered incorrect, you may have to manually remove the credentials from keychain.

At one point, the only way to use a USB drive on another Mac for Time Machine was with the Server app. I seem to recall they may have loosened that requirement n 10.13, but don't quote me. But, you should at least be able to see the files on the drive.
 
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Thanks for reply. The desktop does have the folder shared as a Time Machine destination. I do see the " the folder shared aconnect as" button but when I click it the drive says "not connected". I had not shared the drive itself, just the folder.

For good measure, I shared the drive on the desktop as well. Restarted both computers. Got this error in Time Machine:

The operation couldn’t be completed. (OSStatus error 65.), looking up status error 65 I found:
offLinErr = -65, /*r/w requested for an off-line drive*/
Don't know if this is the 65 I've been getting.
 
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In Finder, use CMD+K to use the menu Go > Connect to Server and enter afp://[ipaddress]/[ShareName] and provide credentials if asked. Then try to select the disk in TM preferences.

Example: afp://192.168.0.5/TimeMachine where 192.168.0.5 is the address of the desktop, and TimeMachine is the share name.
 
Did this used to work, and then for some unknown reason now it does not? If that's the case, have you rebooted both the system where the TM disk is connected, and the affected MBP? Oh, and the router, too. I would try this first.

Or, has it never worked, and you want to know how to make it work?
 
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Did this used to work, and then for some unknown reason now it does not? If that's the case, have you rebooted both the system where the TM disk is connected, and the affected MBP? Oh, and the router, too. I would try this first.

Or, has it never worked, and you want to know how to make it work?

I'm trying to make it work, setting up for first time. I have rebooted everything and problem persists.
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In Finder, use CMD+K to use the menu Go > Connect to Server and enter afp://[ipaddress]/[ShareName] and provide credentials if asked. Then try to select the disk in TM preferences.

Example: afp://192.168.0.5/TimeMachine where 192.168.0.5 is the address of the desktop, and TimeMachine is the share name.

Thanks. I will try as you suggest. Credentials should be for MacBook Pro, correct? Also, I shared the backups.backup.db folder that had been created on the TimeMachine drive by the desktop Mac. Is this ok? Time Machine created a Mac Pro 8 subfolder containing the backup for the desktop Mac and I assumed it would create a MacBook Pro subfolder. Should I share the Time Machine drive itself? Is name of shared folder sufficient or should I enter fullpath?
 
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I've tried all suggestions and nothing seems to be working. After clearing backups.backupdb folder from shares on server machine, I have shared disk Time Machine. On target machine I can mount disk Time Machine but it does not appear in the TM prefs disk options. Is it necessary to mount disk for TM to share? It does not appear in TM disk options, mounted or not.

In Finder "connect to server" window there are several versions of the server under recent servers:
afp://[servername]._afpovertcp._tcp.local
afp://[ip]
smb://[servername]._smb._tcp.local

I guess first two are ok but last is not useful, so I should make sure no Windows sharing is enabled on server machine. Checked and this was apparently residual as only afp is enabled on server.
 
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Running out of ideas... but lets go through the basics.
  1. First, is the external disk formatted properly (HFS+)?
  2. SMB and AFS shares should be fine, Macs are supposed to be able to use SMB shared drives for TM as I recall.
  3. Can the host machine use the locally attached drive for TM backups?
  4. Can other Macs connect using AFS or SMB (not for TM, but for standard file sharing)? Maybe create a Data folder with some file in it and make sure other Macs can access the standard file sharing service.
If #3 is yes, one option may be to connect the drive to each machine in turn, run a backup, then after all Macs have successfully created a backup, re-attach it to the preferred host and see if other Macs can use it given the existing backups.backupdb folder on the disk.

Ot, you could try a visit to an Apple Store and spend a few minutes with a Genius to see if they have insight.
 
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Running out of ideas... but lets go through the basics.
  1. First, is the external disk formatted properly (HFS+)?
  2. SMB and AFS shares should be fine, Macs are supposed to be able to use SMB shared drives for TM as I recall.
  3. Can the host machine use the locally attached drive for TM backups?
  4. Can other Macs connect using AFS or SMB (not for TM, but for standard file sharing)? Maybe create a Data folder with some file in it and make sure other Macs can access the standard file sharing service.
If #3 is yes, one option may be to connect the drive to each machine in turn, run a backup, then after all Macs have successfully created a backup, re-attach it to the preferred host and see if other Macs can use it given the existing backups.backupdb folder on the disk.

Ot, you could try a visit to an Apple Store and spend a few minutes with a Genius to see if they have insight.

Thanks again. 1)The external disk is HFS extended (journaled). 2) I disabled SMB to eliminate extra variables. 3)Host machine is backing up to the external TM disk. The only anomalous thing I have noticed is that sometimes the external drive appears twice in the TM disk options. I'm fairly sure this is due to my playing with the TM prefs by removing and adding the drive I'm using as the TM drive selection, in an effort to clear selections and try something else. 4) The MacBook Pro can connect to host for normal file sharing; host machine can likewise connect normally to the MacBook Pro. Whatever the problem is it seems to be with Time Machine. Apple told me it might be the router, but that would mean there is some special protocol TM needs that the router is blocking. Sounds just wrong to me. Maybe a trip to the Genius Bar is in order. Before I do so I will try backing up directly to the MacBook Pro to see if that would "break the ice," as you suggest. Will keep posting here to document progress for the benefit of others with same problem, and hopefully quick solution. It is seeming like a TM bug. Much appreciate the inputs.
 
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Apple told me it might be the router, but that would mean there is some special protocol TM needs that the router is blocking.
Only protocol I can think of is UPnP.

AFP and Airplay use a non-routable broadcast mechanism to advertise shared resources on the network, kind of like the old WINS service for PCs to discover each other on the LAN. Since broadcast protocols are chatty, they consume network bandwidth. In a home environment, it should not be an issue but some routers disable some of these broadcasts by default. UPnP seems to be the service that most routers use as an umbrella to allow broadcasts to be propagated on the network.
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Apple told me it might be the router, but that would mean there is some special protocol TM needs that the router is blocking.
Only protocol I can think of is UPnP.

AFP and Airplay use a non-routable broadcast mechanism to advertise shared resources on the network, kind of like the old WINS service for PCs to discover each other on the LAN. Since broadcast protocols are chatty, they consume network bandwidth. In a home environment, it should not be an issue but some routers disable some of these broadcasts by default. UPnP seems to be the service that most routers use as an umbrella to allow broadcasts to be propagated on the network.
 
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Addendum I)

I) Time Machine on the MacBook Pro is backing up to the directly connected external Time Machine drive and appears to be functioning nominally.
 
Addendum 2) Apple support informed me that it is not possible to set up a Mac as a Time Machine server and choose an external drive on the Mac as a Time Machine destination on another Mac on the network. This makes perfect sense when one things about it, as this ability would certainly cut into Time Capsule sales. Looks like I will need to purchase a Time Capsule to put the disk on the network, use a separate disk for the MBPro, use iCloud as a TM destination (not preferred given demands for gov. access to data), or simply clone to a shared drive.

I am disappointed and I do apologize for leading this thread on a wild goose chase. In my defense, I read multiple articles from credible sources which praised High Sierra for rolling TM server into the OS and even included detailed instructions on setting up. Moreover, the Apple support rep I spoke with yesterday didn't make it clear that this is not doable after I explained in detail what I wanted to do. Nevertheless, the buck stops here and my bad. The takeaway for me is, don't believe everything you read even from sources which are generally reliable.

I got no information regarding the broadcast protocol Time Capsule relies upon. Although not a tech guy by any means, I would guess it is just some light obfuscation riding on something very universal and standard, as you implied, like UPnP. Thanks again for your very valuable insights and inputs.
 
Addendum 2) Apple support informed me that it is not possible to set up a Mac as a Time Machine server and choose an external drive on the Mac as a Time Machine destination on another Mac on the network. This makes perfect sense when one things about it, as this ability would certainly cut into Time Capsule sales. Looks like I will need to purchase a Time Capsule to put the disk on the network, use a separate disk for the MBPro, use iCloud as a TM destination (not preferred given demands for gov. access to data), or simply clone to a shared drive.

I am disappointed and I do apologize for leading this thread on a wild goose chase. In my defense, I read multiple articles from credible sources which praised High Sierra for rolling TM server into the OS and even included detailed instructions on setting up. Moreover, the Apple support rep I spoke with yesterday didn't make it clear that this is not doable after I explained in detail what I wanted to do. Nevertheless, the buck stops here and my bad. The takeaway for me is, don't believe everything you read even from sources which are generally reliable.

I got no information regarding the broadcast protocol Time Capsule relies upon. Although not a tech guy by any means, I would guess it is just some light obfuscation riding on something very universal and standard, as you implied, like UPnP. Thanks again for your very valuable insights and inputs.

Have you tried creating separate partitions on the shared drive and then using each as a separate TM disk?

I connected to the Mini (where the disk was plugged in) using it's IP and the AFP protocol, connected on my MBP.

This DID work for me in the past, but only with manual backups, and I have not tried it on High Sierra.
 
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Addendum 2) Apple support informed me that it is not possible to set up a Mac as a Time Machine server and choose an external drive on the Mac as a Time Machine destination on another Mac on the network.
I questioned that in my first response, but as I have not kept up on the subject (been using Time Capsule for a few years), I didn't go too deep into it.

If I am not mistaken, the Server app does enable a Mac to share an external drive to other Macs for TM backups. At least it did at one point, but as much as they are deprecating features, I wouldn't be surprised if it has been removed. No bets on future support as they seem to be dropping a lot of server functionality.

You don't necessarily need a Time Capsule. AP Extreme can share USB drives as a TM destination. The Extreme doesn't even need WiFi enabled, nor configured as a router. Since you already have a disk, you could find an Extreme on eBay for under $100 and use it as a TM "Server".

https://support.apple.com/en-us/HT202784

Apple discontinued allowing TM disks on Extremes prior to the AC model which is the tall "cylinder" form factor (like an extra tall AppleTV).

If you go this route, use Ethernet to connect to your router, turn off WiFi, and set Network Mode to Bridged.
 
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Have you tried creating separate partitions on the shared drive and then using each as a separate TM disk?

I connected to the Mini (where the disk was plugged in) using it's IP and the AFP protocol, connected on my MBP.

This DID work for me in the past, but only with manual backups, and I have not tried it on High Sierra.

I didn't partition the time machine drive. If I had gotten the MacBook Pro to recognize it as a TM drive I might have tried something like that, as I would think then it would recognize any shared volume. High Sierra probably did change things and that must be why those articles I saw were incorrect.
 
I questioned that in my first response, but as I have not kept up on the subject (been using Time Capsule for a few years), I didn't go too deep into it.
les
If I am not mistaken, the Server app does enable a Mac to share an external drive to other Macs for TM backups. At least it did at one point, but as much as they are deprecating features, I wouldn't be surprised if it has been removed. No bets on future support as they seem to be dropping a lot of server functionality.

You don't necessarily need a Time Capsule. AP Extreme can share USB drives as a TM destination. The Extreme doesn't even need WiFi enabled, nor configured as a router. Since you already have a disk, you could find an Extreme on eBay for under $100 and use it as a TM "Server".

https://support.apple.com/en-us/HT202784

Apple discontinued allowing TM disks on Extremes prior to the AC model which is the tall "cylinder" form factor (like an extra tall AppleTV).

If you go this route, use Ethernet to connect to your router, turn off WiFi, and set Network Mode to Bridged.

Thanks for suggesting the AP extreme. This is what I will probably do, looking for a tall form factor model. Thanks again for all your help.
 
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Thanks for suggesting the AP extreme. This is what I will probably do, looking for a tall form factor model.

Good luck bidding. With Apple discontinuing AP line, the prices seem to be dropping, but they will be useful for 5-10 years i suspect. By then, there should be plenty of other options.
 
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