# Zarr.jl writing to AWS S3

**URL:** <https://discourse.julialang.org/t/zarr-jl-writing-to-aws-s3/91745>\
**Category:** Data\
**Tags:** question\
**Created:** [December 16, 2022, 3:30pm UTC](https://discourse.julialang.org/t/zarr-jl-writing-to-aws-s3/91745 "2022-12-16T15:30:57Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![sbuczkowski1](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sbuczkowski1/32/45156_2.png) [@sbuczkowski1](https://discourse.julialang.org/u/sbuczkowski1)\
**Post date:** [December 16, 2022, 3:30pm UTC](https://discourse.julialang.org/t/zarr-jl-writing-to-aws-s3/91745/1 "2022-12-16T15:30:57Z")

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Relatively new to julia and jumping into the deep end of the pool trying to test some things for work. Does anyone out there have any pointers they can share on writing zarr data to an S3 bucket? I’ve managed to successfully follow the various examples for reading and writing generic data to buckets as in the AWSS3.jl examples and have managed to read zarr data from S3. However, I am just not figuring out the structure of writing to S3 through Zarr.jl.

One error I keep hitting is:  
ERROR: AWS.AWSExceptions.AWSException: AccessDenied – Anonymous access is forbidden for this operation

which seems to stem from not properly configuring my AWS credentials for the process but, I’m using the same global\_aws\_config() call that successfully got me basic read/write and zarr read so, I guess I am using it incorrectly for the write(?)

Any tips or tricks would be greatly appreciated.

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**Author:** ![alex-s-gardner](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/alex-s-gardner/32/30210_2.png) [@alex-s-gardner](https://discourse.julialang.org/u/alex-s-gardner)\
**Post date:** [December 16, 2022, 4:33pm UTC](https://discourse.julialang.org/t/zarr-jl-writing-to-aws-s3/91745/2 "2022-12-16T16:33:29Z")

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Sometimes it’s helpful to provide a minimum working example, it makes it easier to troubleshoot

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<div class="post-metadata">

**Author:** ![sbuczkowski1](https://sea2.discourse-cdn.com/julialang/user_avatar/discourse.julialang.org/sbuczkowski1/32/45156_2.png) [@sbuczkowski1](https://discourse.julialang.org/u/sbuczkowski1)\
**Post date:** [December 16, 2022, 6:18pm UTC](https://discourse.julialang.org/t/zarr-jl-writing-to-aws-s3/91745/3 "2022-12-16T18:18:36Z")

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Oh, definitely. I’ll try to sort through the spaghetti I am throwing at the wall and see if I can bring some better focus.