I wasn't sure if I should've added this to #692 or not, but /proc isn't really a place you want to backup, and this happened on a normal place to backup. I apologize if adding it to that issue was better.

Output of restic version

restic 0.9.3 compiled with go1.11.1 on linux/amd64

How did you run restic exactly?

From cron:

MAILTO=""
SHELL=/bin/sh
PATH=/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/bin
RESTIC_REPOSITORY=azure:<hidden>
RESTIC_PASSWORD=<hidden>
AZURE_ACCOUNT_NAME=<hidden>
AZURE_ACCOUNT_KEY=<hidden>
0 */4 * * * restic restic backup /var/www/nextcloud/data >>/var/log/restic/restic.log 2>>/var/log/restic/error.log

Stderr output:

error: lstat /var/www/nextcloud/data/test.user/uploads/1036227155/00000005: no such file or directory
error: NodeFromFileInfo: Listxattr: xattr.list /var/www/nextcloud/data/test.user/uploads/1036227155/00000004 : no such file or directory

What backend/server/service did you use to store the repository?

Azure Blob Storage

Expected behavior

Restic not throwing errors.

Actual behavior

Restic throws this error. The backup still seems to have succeeded.

Steps to reproduce the behavior

Unknown

Do you have any idea what may have caused this?

It seems to me that this file was removed from the file system between when restic found out the file existed and tried to back it up. So a race condition.

Do you have an idea how to solve the issue?

It's hard to tell, especially because you probably want to avoid hiding actual errors. But this error message seems to not be an actual issue, so we probably don't want it logged to the error log.

Did restic help you or made you happy in any way?

Yup, it's the first backup solution I've tried in ages that doesn't feel awful to use :)