Mirroring Certificate Expired is an SQL error that indicates that the certificate used by the mirroring endpoint has expired.
The error message related to this issue can also be that the certificate used by the mirroring endpoint can’t be found.
More details related to this issue can be found in our article SQL: MIRROR NOT CONNECTED.
Find out how you can save hours of work when investigating the root cause of this issue.
Symptoms
The connection between a primary SQL database and its mirror database has been lost.
Impact: High
Database mirroring in SQL Server allows to keep a copy or mirror a SQL Server database on a standby server.
Mirroring ensures that two separate copies of the data exist at all times, providing high availability and complete data redundancy.
When mirroring is disconnected this recovery solution won’t be available in the case of disaster.
Expected behavior
The mirror should remain connected and active.
1- Certificates are no longer valid. Priority: High
As the certificates are no longer valid, new certificates need to be created with future expiry_dates. If no expiry_date is given while creating the certificates, the default is one year expiration of the certificates.
Problem identification:
Search for errors related to mirroring issues.
- Investigate the SQL Server Logs of the mirrored servers. The disadvantage of this manual check is that you will probably find out about this issue too late after it has started.
- Check for the exception description and if it mentions that the certificate which is related to mirroring has expired.
Recommended action :
There is one solution – creating new certificates for SQL Server Database Mirroring while cleaning old SQL Server Database Mirroring certificates. It’s recommended to follow up on this issue with a monitoring tool.
