Hi @Nagashree Balasundaram Thanks for reaching out.
Validate certificate Name: By default, APIM doesn't validate backend certificate names. You can enable this by creating a Backend entity representing your backend and selecting "Validate certificate name" option.
Validate certificate chain: If your backend is using a self-signed certificate/ SSL certificate issued by a Custom CA APIM doesn't trust those certificates in this case you can set validate certificate chain to false so that APIM will not validate it.
If you need to validate the backend certificate chain for self-signed certificate/ SSL certificate issued by a Custom CA you will need to upload the root and intermediate certificates used by the backend into APIM (Certificates --> CA Certificates)
Do let me know if you have any queries.
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