Hi @ajay gupta ,
Please refer to this official document: KB4041553 - SQL Server Service Packs are discontinued starting from SQL Server 2017.
Starting from SQL Server 2017:
- SPs will no longer be available. Only Cumulative Updates (CUs) and critical updates (GDRs) will be provided.
- CUs will contain localized content if it's necessary as what SPs have done.
- CUs will be delivered more frequently at first and then less frequently: every month for the first 12 months, and then every quarter for the final four years of the five-year mainstream lifecycle.
Here is an document about SQL Server 2017 build versions: KB4047329. You can select the latest cumulative update to install.
In addition, to upgrade a SQL Server failover cluster instance, use SQL Server setup to upgrade each node participating in the failover cluster instance, one at a time, starting with the passive nodes. As you upgrade each node, it is left out of the possible owners of the failover cluster instance. If there is an unexpected failover, the upgraded nodes do not participate in the failover until Windows Server failover cluster role ownership is moved to an upgraded node by setup.
Seeya Xi
Best regards
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