Extra clarification

[gbaeke]

Please clarify when the DHCP lease expires. If it is like virtual machines (>100 years), we can wait for a long time. Also clarify what "platform upgrade" means exactly.

Note there is a typo as well: upgarade instead of upgrade.

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Document Details

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• ID: a3a243b5-d841-5848-5dd6-92f367a254b3
• Version Independent ID: 6d7a4a79-d20a-68f8-8406-a3e0d2e3dcc3
• Content: Managed instance custom DNS - Azure SQL Database
• Content Source: articles/sql-database/sql-database-managed-instance-custom-dns.md
• Service: sql-database
• Sub-service: managed-instance
• GitHub Login: @srdan-bozovic-msft
• Microsoft Alias: srbozovi

[Mike-Ubezzi-MSFT]

@gbaeke Thank you for bringing this to our attention. I have corrected the spelling issue, and working to provide feedback with regard to DHCP leases. Platform upgrade could be better worded as it is vague to what exactly it refers.

[Mike-Ubezzi-MSFT]

@srdan-bozovic-msft Is there additional clarification you can provide with regard to platform upgrade ? @stevestein for awareness.

[ChrisMenegay]

Is there a way to force the DHCP lease to renew? We implemented a CNAME for our Azure SQL MI and are getting "target principal name is incorrect". I'm hopeful the DHCP renew will get that working. Or perhaps not, there is a pretty big lack of information on setting up a custom DNS name for Azure SQL MI

[JustenCs]

I'd like to echo @ChrisMenegay's point above. How do we go about using our own DNS zones to reference SQL MI? I get the same 'error' If it were on prem, I'd add an SPN.
Thanks,
Charlie

[ChrisMenegay]

@JustenCs I ended up reaching out to Support. The DNS name must match the SQL MI. For example, if your DB is foo.mar1314234235.database.windows.net your local DNS MUST match the server name, so it could be: foo.contoso.com I did that and was able to connect, but I still have to "Trust Server Certificate" when connecting with AD accounts.

[JustenCs]

@ChrisMenegay thank you! Did you create an A record or CNAME?

[ChrisMenegay]

@JustenCs CNAME

[npigit]

@Mike-Ubezzi-MSFT Have you received a feedback regarding the DHCP lease time? I would like to know how long it will to take effect when the custom DNS is configured after the azure SQL Managed Instance provisioning.

[Nash-Vegas]

Also need to know this information, thank you.

[srdan-bozovic-msft]

updating dns servers on demand is now available and article is updated to reflect that
https://docs.microsoft.com/en-us/azure/azure-sql/managed-instance/synchronize-vnet-dns-servers-setting-on-virtual-cluster

as for the lease, it's indefinite but as we do updates monthly it would not take longer than month for the update

#please-close