Origin groups greatly increasing health probe frequency?

[ththiem]

Hello,

https://learn.microsoft.com/en-us/azure/frontdoor/health-probes#how-front-door-determines-origin-health

Looking at this section, there's a note here about

"If a single endpoint is a member of multiple origin groups, Front Door will optimize the number of health probes sent to the origin to reduce the load on the origin. Health probe requests will be sent based on the lowest configured sample interval. The health of the endpoint in all origin groups will be determined by the responses from same health probes."

We tried adding a few origin groups to our AFD in order to organize and prioritize endpoints by region in order to have "regional" domain endpoints, but we found that doing so more than quadrupled the amount of health probes that were being sent to our backends which brought down our apps due to sheer volume, contrary to what the above note says about that. Is this expected? We made no change to health probe frequency, it was left at the default 30s value.

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Document Details

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• ID: f35a0b39-ab2f-ba8a-0907-e0f3a6b69135
• Version Independent ID: 0e6c8267-a911-9c6b-0522-3ec96753b3ef
• Content: Health probes - Azure Front Door
• Content Source: articles/frontdoor/health-probes.md
• Service: frontdoor
• GitHub Login: @duongau
• Microsoft Alias: duau

[ChaitanyaNaykodi-MSFT]

@ththiem
Thank you for reaching out.
As we primarily monitor this channel for documentation enhancements/bugs. I am reaching out to you internally regarding this question and will share PG contacts. Please do not forget to add additional details in your question about the endpoint and it is part of how many origin groups. Thank you!