# Fetch error: "unable to calculate the md5 sum of the remote file"

**URL:** <https://forum.ansible.com/t/fetch-error-unable-to-calculate-the-md5-sum-of-the-remote-file/17273>\
**Category:** Ansible Project\
**Tags:** ubuntu\
**Created:** [January 14, 2015, 8:08pm UTC](https://forum.ansible.com/t/fetch-error-unable-to-calculate-the-md5-sum-of-the-remote-file/17273 "2015-01-14T20:08:38Z")\
**Posts on this page:** 3\
**Page:** 1

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**Author:** ![Kevin\_Lasenby](https://avatars.discourse-cdn.com/v4/letter/k/df705f/32.png) [@Kevin\_Lasenby](https://forum.ansible.com/u/Kevin_Lasenby)\
**Post date:** [January 14, 2015, 8:08pm UTC](https://forum.ansible.com/t/fetch-error-unable-to-calculate-the-md5-sum-of-the-remote-file/17273/1 "2015-01-14T20:08:38Z")

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When trying to fetch a file from a Synology NAS to my Ansible server (Ubuntu, using SSH keys) I get the error “unable to calculate the md5 sum of the remote file”.

I don’t get this error fetching from any other server and can’t find any information on what’s causing it. Any ideas?

Kevin

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**Author:** ![Toshio\_Kuratomi](https://avatars.discourse-cdn.com/v4/letter/t/41988e/32.png) [@Toshio\_Kuratomi](https://forum.ansible.com/u/Toshio_Kuratomi)\
**Post date:** [January 14, 2015, 11:53pm UTC](https://forum.ansible.com/t/fetch-error-unable-to-calculate-the-md5-sum-of-the-remote-file/17273/2 "2015-01-14T23:53:33Z")

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In ansible 1.7.x and below, ansible looked for a program on the remote  
machine to do an md5sum of the file for integrity checking. As of  
1.8.0, ansible uses python itself to create a sha1 hash for integrity  
checking. What this means is that on ansible-1.7.x and older you  
needed to have /usr/bin/md5sum, /usr/bin/md5, or another of a few  
known programs in order to use many file related modules. With  
current ansible you'll only need python installed.

-Toshio

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<div class="post-metadata">

**Author:** ![Kevin\_Lasenby](https://avatars.discourse-cdn.com/v4/letter/k/df705f/32.png) [@Kevin\_Lasenby](https://forum.ansible.com/u/Kevin_Lasenby)\
**Post date:** [January 15, 2015, 2:59am UTC](https://forum.ansible.com/t/fetch-error-unable-to-calculate-the-md5-sum-of-the-remote-file/17273/3 "2015-01-15T02:59:10Z")

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Thanks for the reply. Looks like md5sum/md5 isn’t available for Synology, at least I know why its failing and can work around the issue.

Kevin