Client broken under macOS 27

Derda · September 21, 2026, 12:29pm

Hi,

For a couple of months, I have been running the 2.5.30 client on macOS 26 backing up to a 2.5.37 server on a Synology NAS on the same network. Since last week I get errors, probably related to the update to macOS 27.

Here is the relevant part from the client log:

2026-09-21 14:07:18: Snapshot mounted at /Volumes/urbackup_snaps/8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e
2026-09-21 14:07:18: Shadowcopy path: /Volumes/urbackup_snaps/8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e
2026-09-21 14:07:18: done.
2026-09-21 14:07:18: Removing deleted directories from index for "/"...
2026-09-21 14:07:18: Scanning for changed hard links on volume of "/"...
2026-09-21 14:07:18: Disabling CBT on volume ""
2026-09-21 14:07:18: Indexing "rootfs"...
2026-09-21 14:07:18: [macOS] Skipping "/home" due to macOS exclusion "/home*"
2026-09-21 14:07:18: [macOS] Skipping "/.fseventsd" due to macOS exclusion "/.fseventsd*"
2026-09-21 14:07:18: [macOS] Skipping "/.TemporaryItems" due to macOS exclusion "/.TemporaryItems*"
2026-09-21 14:07:18: [macOS] Skipping "/.Spotlight-V100" due to macOS exclusion "/.Spotlight-V100*"
2026-09-21 14:07:18: [macOS] Skipping "/.DocumentRevisions-V100" due to macOS exclusion "/.DocumentRevisions-V100*"
2026-09-21 14:07:26: ClientService cmd: #ICAz5w0TDgKbMXfYThv2l#2PING RUNNING pc_done=&eta_ms=1525172&status_id=166&speed_bpms=0&total_bytes=-1&done_bytes=0&paused_fb=1#token=2NFgdVAnAX5JQ7WUdDO3
2026-09-21 14:07:28: [macOS] Skipping "/Library/Updates" due to macOS exclusion "/Library/Updates*"
2026-09-21 14:07:28: [macOS] Skipping "/Library/Trial" due to macOS extended attribute exclusion
2026-09-21 14:07:28: [macOS] Skipping "/Library/Application Support/Apple/AssetCache/Data" due to macOS extended attribute exclusion
2026-09-21 14:07:29: ERROR: Cannot stat "/Volumes/urbackup_snaps/8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e/Library/Caches/com.apple.amsengagementd.classicdatavault": Operation not permitted (1)
2026-09-21 14:07:29: ERROR: Cannot stat "/Volumes/urbackup_snaps/8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e/Library/Caches/com.apple.aneuserd": Operation not permitted (1)
2026-09-21 14:07:29: ERROR: Cannot stat "/Volumes/urbackup_snaps/8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e/Library/Caches/com.apple.aned": Operation not permitted (1)
2026-09-21 14:07:29: ERROR: Error while listing files in folder "/Volumes/urbackup_snaps/8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e/Library/Caches". User may not have permissions to access this folder. Errno is 0
2026-09-21 14:07:29: Deleting shadowcopy for path "/Volumes/urbackup_snaps/8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e" -2
2026-09-21 14:07:29: Deleted local snapshot '2026-09-21-140716'
2026-09-21 14:07:29: Deleting Shadowcopy for dir "/"

Permissions on the snapshot look like this:

bodo@Macncheese ~ % ls -al /Volumes/urbackup_snaps
total 8
drwxr-xr-x   4 root  wheel  128 21 Sep. 14:07 .
drwxr-xr-x   8 root  wheel  256 21 Sep. 12:48 ..
drwxr-xr-x@ 22 root  wheel  704 19 Sep. 01:26 8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e
-rw-r--r--   1 root  wheel   18 21 Sep. 14:07 8c231c5e04081a60d2d485c6365c58cf238f74a0cd37268e-snap-date

FWIW, urbackupclientbackend runs with UID 0, urbackupclientgui UID 501.

I’m stymied. Any ideas where to look?

Bodo

uroni · September 22, 2026, 5:44pm

Does it work if you exclude /Library/Caches from backups or does that just make it run into the next problem?

Derda · September 23, 2026, 9:19am

I tried to exclude the directory

but it still complains about the same files in that directory.

The thing is: root can’t stat the files either:

Macncheese:~ root# whoami
root
Macncheese ~ root# ls -al /Volumes/urbackup_snaps/5a8d981cb18d3e193a4c4f55b739477fba3c41993925498d/Library/Caches
ls: com.apple.amsengagementd.classicdatavault: Operation not permitted
ls: com.apple.aned: Operation not permitted
ls: com.apple.aneuserd: Operation not permitted
total 0
drwxrwxrwt    9 root            admin    288 18 Sep. 15:49 .
drwxr-xr-x   66 root            wheel   2112 18 Sep. 14:58 ..
drwxr-xr-x@   3 root            admin     96 18 Sep. 14:58 ColorSync
drwx--x--x  591 _iconservices   admin  18912 23 Sep. 10:51 com.apple.iconservices.store
drwxr-xr-x    3 _modelmanagerd  admin     96 18 Sep. 15:49 com.apple.InferenceProviderService
drwxr-xr-x    3 root            admin     96 18 Sep. 14:58 Desktop Pictures
ls: fts_read: Operation not permitted

And yes, Full Disk Access is turned on for UrBackup Client and iTerm/Terminal.

Derda · September 23, 2026, 11:11am

I searched for other files that run into Operation not permitted when ls’ed by root (sudo ls -alR / 2>&1 | grep permitted). There are more residing in these directories or subdirectories thereof:

/private/var/containers/Data/ProtectedSystem
/private/var/db
/private/var/folders
/private/var/networkd/db
/private/var/OOPJit
/private/var/protected/trustd/private
/System/Library/AssetsV2
/System/Volumes/Data/private/var/containers/Data/ProtectedSystem

I don’t have access to a machine with macOS 26, so I don’t know whether that behavior has changed with Golden Gate.

uroni · September 23, 2026, 6:25pm

Perhaps try the exclude without the wildcard additions

Derda · September 24, 2026, 11:11am

Makes no difference.

In fact, should it even be necessary to exclude this as “/Library/Caches/*” is by default excluded in line 5167 of urbackupclient/client.cpp?

And shouldn’t line 133 of urbackupcommon/os_functions_lin.cpp produce a “Skipping due to macOS SIP restriction” log entry for “/Library/Caches/com.apple.aned”?

In addition to the files listed in these two places I see a couple of other files or directories on my system that I cannot stat:

/Library/Caches/com.apple.amsengagementd.classicdatavault
/Library/Caches/com.apple.aneuserd
/private/var/containers/Data/ProtectedSystem/
/private/var/db/AppleIntelligencePlatform/
/private/var/db/ExtensibleSSO/Configuration
/private/var/db/installcoordinationd/
/private/var/db/rmd/
/private/var/db/SoC/
/private/var/db/SystemKeys/
/private/var/OOPJit/
/System/Library/AssetsV2/com_apple_MobileAsset_UAF_FM_GenerativeModels/
/System/Library/AssetsV2/com_apple_MobileAsset_UAF_FM_Overrides/
/System/Library/AssetsV2/com_apple_MobileAsset_UAF_FM_Visual/
/System/Library/AssetsV2/com_apple_MobileAsset_UAF_IF_Planner/
/System/Library/AssetsV2/com_apple_MobileAsset_UAF_IF_PlannerOverrides/