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Scott Reed
Mar 23, 2023
  2875
(5 votes)

Fixing Optimizely Content Syncing/Caching Issues on the DXP pre CMS.Core 12.13.0

Hi all,

With our recent deployments to the DXP for .NET 6 projects (one a new build and one an upgrade) our clients had raised issues where there were seeing different data for the same items within the CMS. For one of our clients on Optimizely Commerce they were seeing 1 variant on a product and a different editor was seeing 3 variants. 

Vs

This was a big issue and raised the problem that not only would this be affecting users, end customer would be seeing the different data.

We managed to replicate this by faking the users ARRAffinity value so we could see that this was related to specific instances.

On an investgation by support this has raised that there was a scaling bug on the caching system fixed on bug https://world.optimizely.com/support/bug-list/bug/CMS-26486 

As this is a fairly critical issue I wanted to highlight this and strongly suggest customers on the DXP to upgrade to a minimum version of 12.13.0 (12.13.1 See below) as we are doing for our client.

Thanks!!

Update to this: Quan Mai pointed out some other fixes recently which means we should be upgrading to 13.13.1 https://world.optimizely.com/blogs/Quan-Mai/Dates/2023/3/upgrade-to-episerver-cms-core-12-13-1-as-soon-as-you-can/ 

Mar 23, 2023

Comments

Mark Stott
Mark Stott Mar 24, 2023 01:25 PM

Thank you for sharing.

Quan Mai also shared the need to update to 12.31.1 due to a critical issue the other day. So if you're going to update to 12.13.0, go all the way to 12.13.1 instead.

https://world.optimizely.com/blogs/Quan-Mai/Dates/2023/3/upgrade-to-episerver-cms-core-12-13-1-as-soon-as-you-can/

Scott Reed
Scott Reed Mar 24, 2023 02:47 PM

Thanks Mark, I did actually read that article but forgot and was asked to blog about this so cracked it out quick. Have updated the article to reflect!

Eemgo
Eemgo May 5, 2025 08:33 AM

We are seeing the same issue and we are currently on EPiServer.CMS 12.32.4. Just like @Scott wrote, we can force the issue by modifying the ARRAffinity value. In our case, a multitude of issues but they are mostly related to pages being moved from one place to another, (eg restored from the recycle bin). For such a age, some instances would throw a 404, whilst others can fetch/display the restored content successfully.

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