Internal System Error in Azure Cosmos DB Mirroring in Fabric

[subin_k]

Hi all,

I’m encountering an issue with Azure Cosmos DB mirroring in Microsoft Fabric. I created a mirrored database with multiple containers about six months ago, and it has been working fine until today.

Now, a few containers have stopped replicating and are showing a status of "Running with warning". The warning details state:

"Internal system error occurred. ArtifactId:"

Notably:

• No changes were made to the Cosmos DB source.

• Replication is still working for some containers.

• I’ve tried:

  • Restarting replication

  • Refreshing metadata in the SQL analytics endpoint
    But the issue still persists.

Has anyone else run into a similar problem? Any suggestions on how to troubleshoot or resolve this?

Thanks in advance for any insights!

[v-tsaipranay · Accepted solution]

Hi @subin_k ,

Thanks for reaching out to the Microsoft Fabric Community.

The warning message you're seeing “Internal system error occurred. ArtifactId:” usually means that something went wrong while syncing a specific container. Since other containers are still working and you haven’t made changes to the Cosmos DB source, this issue might be related to unsupported data types, unusual schema patterns, or internal issues with just those specific containers.

You’ve already tried restarting replication and refreshing metadata, which is great. Here are a few more things you can try:

1. Turn off mirroring for the affected containers, wait a bit, and then turn it back on. This often helps reset the sync and can fix temporary issues.
2. Check the Cosmos DB container settings. Look for any changes in TTL policies, indexing, throughput settings (manual vs. autoscale), or if there are deeply nested JSON objects or unsupported types like binary data. These can sometimes break the sync process.
3. Check the Monitor tab in your Fabric workspace to see if there are any detailed error logs tied to the ArtifactId. This might give you more clues about what's going wrong.

For more information, you can also look at this doc that explains supported limits and scenarios for Cosmos DB mirroring in Fabric:
Limits and Quotas for Cosmos DB Mirroring in Fabric (Preview)

I hope this will resolve your issue, if you need any further assistance, feel free to reach out.

If this post helps, then please give us Kudos and consider Accept it as a solution to help the other members find it more quickly.

Thankyou.

[v-tsaipranay]

Hi @subin_k ,

I wanted to check if you had the opportunity to review the information provided. Please feel free to contact us if you have any further questions. If my response has addressed your query, please accept it as a solution and give a 'Kudos' so other members can easily find it.

Thank you.

[Mathan1787]

Hi, I am getting a same error while mirroring the mongodb, using code provided by mongodb for mirroring. 

how can i monitor for detailed information about error?  i can only see - Internal system error occurred. ArtifactId:"  there are still same data in that collections. while transfering I have converted all the datatype either to string or to decimals and my primary key is always string. 

[v-tsaipranay]

Hi @subin_k   ,

May I ask if you have resolved this issue? If so, please mark the helpful reply and accept it as the solution. This will be helpful for other community members who have similar problems to solve it faster.

Thank you.

[v-tsaipranay]

Hi @subin_k   ,

May I ask if you have resolved this issue? If so, please mark the helpful reply and accept it as the solution. This will be helpful for other community members who have similar problems to solve it faster.

Thank you.