Hi Joe Kim (Admin) ,
Welcome to the Microsoft Q&A Platform! Thank you for asking your question here.
We understand from your query that you are experiencing an issue with an expired Microsoft Azure TLS certificate issued by DigiCert, which is affecting your intra-server connectivity.
The certificates in the Microsoft Azure TLS Issuing CA 01, 02, 05, and 06 have expired.
The certificates Microsoft Azure TLS Issuing CA 03, 04, 07, and 08 will replace those in Microsoft Azure TLS Issuing CA 01, 02, 05, and 06. Depending on which certificate your service uses to establish TLS connections, action may be needed to prevent loss of connectivity.
For more information about the Azure Certificate Authority (CA), please refer to this https://learn.microsoft.com/en-us/azure/security/fundamentals/azure-ca-details?tabs=root-and-subordinate-cas-list#subordinate-certificate-authorities
If you have any further queries, do let us know.
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