idevicebackup2 backup -- ErrorCode 104: Error removing snapshot directory about libimobiledevice

[nikias]

After getting this error, can you please paste the output of

ls -l tmp/origin_1/3479d2dacfc1dd6b673a49ca1be89611913a64ec/Snapshot

so we can see what is still there?

[bucktaiwan]

There are still 56024 files stayed in Snapshot directory

Could not attach file and so, I pasted some of them as follows:
total 56024
-rw-r--r-- 1 root root 7440 Jan 1 2000 00c635a5f9aed1c67dd2706e4fea9a4e3d6d92ef
-rw-r--r-- 1 root root 5584 Jan 1 2000 011faf71b3be046167ec59570d46c0a785f04261
-rw-r--r-- 1 root root 9968 Jan 1 2000 01b2fc37070306401c4a940142d5d616dd35dbea
-rw-r--r-- 1 root root 9312 Jan 1 2000 020725158572c687953a18ea075a21ddaa25ce9c
-rw-r--r-- 1 root root 2192 Jan 1 2000 02aa0a8aa65487d490cce0287568c4136b3e431a
-rw-r--r-- 1 root root 8208 Jan 1 2000 04839f6e9f83bc33cfcdba9150e4805fb9254f98
-rw-r--r-- 1 root root 8320 Jan 1 2000 051c2628a5c37f83e1cbb5106d17ce5501e7a06b
-rw-r--r-- 1 root root 6768 Jan 1 2000 06653ca7cfbcabe4f938028343bf8327ab972757
-rw-r--r-- 1 root root 357920 Jan 1 2000 06d118f21d274ca304d12f8812d56cb9c74469f9
-rw-r--r-- 1 root root 7904 Jan 1 2000 07c986b45ffac879f60b3edd8f1e82e3f5076342
-rw-r--r-- 1 root root 8608 Jan 1 2000 086fc1c2a877e39854c2cc2ab2738801f207afa2
-rw-r--r-- 1 root root 9312 Jan 1 2000 0959eb9b13976117ee079f4d0684dc83673b1fb1
-rw-r--r-- 1 root root 8928 Jan 1 2000 0a54f12201cbafbf40c54fd3030a72e9948b89dd
-rw-r--r-- 1 root root 8960 Jan 1 2000 0c41d3712cbc726063cfb47e2286f97a0d1ff0e0
-rw-r--r-- 1 root root 5584 Jan 1 2000 0c69fe4d3c6cfb0764c9ce332e87f0ca5baed50d
-rw-r--r-- 1 root root 9424 Jan 1 2000 0cdab3bac3c7d413c9cc6fe2b343f06fd2c714e7
-rw-r--r-- 1 root root 5728 Jan 1 2000 0d5f52200c437532db35b0f96c286338ab89b588
-rw-r--r-- 1 root root 357920 Jan 1 2000 0f0c561d8ae5359a919e8b768ef2cefcd9055f3e
-rw-r--r-- 1 root root 7440 Jan 1 2000 1003812601848ab6f3bb88341b9e2b41e00258b5
-rw-r--r-- 1 root root 6992 Jan 1 2000 11291b6a5707b99848b1560aa7a0b73655750183
-rw-r--r-- 1 root root 8960 Jan 1 2000 1250ffa82fddf01e2ca43d3ad16d8bc604235614
-rw-r--r-- 1 root root 8480 Jan 1 2000 13ff880ed54464947dadd379808e0225fb9bb8d6
-rw-r--r-- 1 root root 357920 Jan 1 2000 1462660000cfde2cbe4476057c09226cc8f19c54
-rw-r--r-- 1 root root 9424 Jan 1 2000 149d82f96b199a37132a2cfcb94bc5e2bd546e88
-rw-r--r-- 1 root root 9344 Jan 1 2000 1565358dfd2517186e0d9687ef3cbef05d1a41cf
-rw-r--r-- 1 root root 6832 Jan 1 2000 157011f4c6f81098480a09525b4c83f489c27a51
-rw-r--r-- 1 root root 9664 Jan 1 2000 162c036d6d7e2a0f6cf05804be0082616d360e50
-rw-r--r-- 1 root root 9968 Jan 1 2000 16a8a3e23b413b0b12db0c02215b6f6f27c40fcc
-rw-r--r-- 1 root root 237872 Jan 1 2000 19ba9f97e1b9bdc5a453546a5b2c7d7538c52090
-rw-r--r-- 1 root root 239216 Jan 1 2000 1a33dd5f9608ad097294052720b09cbda12f24d6
-rw-r--r-- 1 root root 8608 Jan 1 2000 1aaafa66ae7a920690c477e31b700dd8ce913e86
-rw-r--r-- 1 root root 10720 Jan 1 2000 1e5ad65e97cbdda2ebedf22916927e8759ba18df

if you need more, please let me know. Thank you.

[nikias]

That's really weird. Does it also happen if you use a new, empty backup folder?
The file modification time of Jan 1 2000 is also strange..

[nikias]

Closing. I'm pretty sure this happened because of a previously failed backup. Remove the backup directory for that device and use a new, empty one. Then it should work.

[bucktaiwan]

To utilize incremental backup, we did not cleanup backup directory, even when backup failed. So, you might be right.
I will try to see whether or not cleaning up backup directory when failure occurred help resolve this issue.

[unhammer]

Just saw this one myself (with Version: 1.2.0+dfsg-3.1ubuntu1), twice in a row so it's definitely not that I'm changing anything while it's running.

Does this error only happen after everything has been copied over and idevicebackup2 is cleaning up, or are there still files that will not be copied over because this error occurred?

[corsac-s]

@unhammer which version do you have / on which distribution, and which iOS version is it?

I'm experiencing the same this on Debian sid with libimobiledevice 1.2.0+dfsg-3.2 with iOS 11.1.1, but not when I'm using a version built myself from the git. It'd be nice to have a point release of libimobiledevices including the fixes in master.

[unhammer]

Version: 1.2.0+dfsg-3.1ubuntu1

so I was one point behind your 1.2.0+dfsg-3.2; last tested on Xubuntu 17.04