# Automatically exclude Time Machine excluded files

**URL:** <https://kopia.discourse.group/t/automatically-exclude-time-machine-excluded-files/368>\
**Category:** Feature Requests\
**Created:** [April 11, 2021, 7:08pm UTC](https://kopia.discourse.group/t/automatically-exclude-time-machine-excluded-files/368 "2021-04-11T19:08:18Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![saspus](https://yyz2.discourse-cdn.com/free1/user_avatar/kopia.discourse.group/saspus/32/130_2.png) [@saspus](https://kopia.discourse.group/u/saspus)\
**Post date:** [April 11, 2021, 7:08pm UTC](https://kopia.discourse.group/t/automatically-exclude-time-machine-excluded-files/368/1 "2021-04-11T19:08:18Z")

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On macOS applications can mark transient and cache files with an extended attribute `com.apple.metadata:com_apple_backup_excludeItem` to inform time machine that those files and directories should not be backed up. Since the application developers have much better idea about what files need and need not be preserved this approach works better than centralized exclusion list.

Some notable third party backup tools (Duplicacy, Arq, CrashPlan) support exclusion by that attribute as well.

Kopia should too. This cuts down drastically on the need for the user to write (and maintain!) elaborate exclusion patters.

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**Author:** ![ouvoun](https://avatars.discourse-cdn.com/v4/letter/o/90ced4/32.png) [@ouvoun](https://kopia.discourse.group/u/ouvoun)\
**Post date:** [November 28, 2021, 7:58pm UTC](https://kopia.discourse.group/t/automatically-exclude-time-machine-excluded-files/368/2 "2021-11-28T19:58:59Z")

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Would like to +1 this request. Would love to switch to Kopia but the burden of creating an enormous exclusion list is too high.

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**Author:** ![jkowalski](https://yyz2.discourse-cdn.com/free1/user_avatar/kopia.discourse.group/jkowalski/32/3_2.png) [@jkowalski](https://kopia.discourse.group/u/jkowalski)\
**Post date:** [November 28, 2021, 8:05pm UTC](https://kopia.discourse.group/t/automatically-exclude-time-machine-excluded-files/368/3 "2021-11-28T20:05:18Z")

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Filed [Automatically exclude Time Machine excluded files · Issue #1539 · kopia/kopia · GitHub](https://github.com/kopia/kopia/issues/1539) to track.

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**Author:** ![saspus](https://yyz2.discourse-cdn.com/free1/user_avatar/kopia.discourse.group/saspus/32/130_2.png) [@saspus](https://kopia.discourse.group/u/saspus)\
**Post date:** [November 28, 2021, 9:41pm UTC](https://kopia.discourse.group/t/automatically-exclude-time-machine-excluded-files/368/4 "2021-11-28T21:41:55Z")

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A little noteworthy bit: a few folders are excluded by time machine implicitly, without relying on the xattr. Those folders are (at least; using the .kopiaignore syntax):

```auto
**/Library/Logs/**
 **/Library/Caches/**
 **/.Trash/**

```

First two are directly under `~`, `/`, as well as inside Containers, and the last one — under `~`, for each user.

Those exclusions should be added implicitly when exclusion by time machine is enabled by the user.

(Glad to see the FR gets some traction, OTOH I could have filed the GitHub issue myself and avoid 8 month gap…)