Connecting to another Mac via SMB3.0 protocol results in hang at shutdown or restart
Number:rdar://23684301 Date Originated:11/30/2015
Status:Duplicate/19742550 Resolved:
Product:OS X Product Version:10.11
Classification: Reproducible:Always
I am experiencing a bug that causes an endless spinning / spinner hang at restart or shut down if I have EVER connected to another Mac via SMB (cmd+K, smb://foo/bar) during that session

▪︎ The critical difference seems to be SMB3.0, SMB2 or CIFS mounts do not trigger the bug

▪︎ If you simply CONNECT but do not actually attach to any shares, the bug will not manifest

▪︎ Disconnecting the share before restarting does not fix the problem

▪︎ Starting up in SAFE MODE (holding shift) does NOT avoid the problem

Steps to Reproduce:
1. connect from Mac #1 (running ElCap 10.11.x) to Mac #2 (also running ElCap 10.11.x) via smb://mac2/share

2. attach and browse a shared folder

3. try to restart Mac #1

Expected Results:
Mac should restart cleanly

Actual Results:
Screen turns black with a white "spinner" in the middle, which will stay there until the end of time. I have left it there for 8+ hours (overnight) and it never stops. The only way out at this point it to hold down the power button until the Mac shuts off.

Tested with OS X 10.11.1, 10.11.2, 10.11.3, 10.11.4, 10.11.5 and 10.11.6

I have other SMB3.0 servers (Synology NAS, Windows 2012 server) and connecting to those does NOT cause the bug to trigger. It only seems to happen when connecting to another MAC


This issue seems still reproducible on 10.14.4 (18E226)

Apple just closed my bug. They said basically "it's too old, file a new one"

I filed a new one with the same details... #27656700

I will close this and open a new rdar for it.

By at Aug. 2, 2016, 12:51 p.m. (reply...)

There are some additional steps/notes that will make this easier to reproduce:

1) when you connect from the CLIENT to the SERVER Mac, connect as an ADMINISTRATIVE user that has access to the / of the hard drive.

2) When you get the dialog box asking you to choose from the list of shares after the initial SMB connection, connect to the ROOT OF THE HARD DRIVE

3) Once the remote disk is mounted, navigate into the /Applications folder of the target machine. The Finder will "spin" for a while while all of these files are enumerated. Wait for the list of icons to appear.

4) Now, try to reboot the CLIENT Mac. You will get a hang.

I even reproduced this in a Parallels Virtual Machine -- 100% CLEAN INSTALL of 10.11.6 not a single thing done to it.

By at July 31, 2016, 9:57 p.m. (reply...)

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