The first task of any user considering a server upgrade is deciding on the right upgrade method.
Some people prefer to perform side-by-side upgrades, but they are only applicable for users with a separate hardware and resources to provide a readily available reversion strategy. These take longer and cost more. But downtime can be minimised by compartmentalising to individual applications only.
Others choose an in-place upgrade, also known as the all-or-nothing approach. True to this depiction, an in-place upgrade poses greater risks in the event of an upgrade failure that occurs when even one database does not work properly on the new server and requires a do-over, doubling up cost and time.
Let Professionals Handle It
Here’s a reminder for those who plan to launch an upgrade on their own: without proper due diligence, it can lead to databases that no longer function correctly or worse yet, void an application vendor’s support agreement. This should convince any business outfit to hire SQL server consulting professionals for adequate guidance and assistance. Due to the risks in handling important information systems, this may be a task that you cannot perform hands-on.
Here are other considerations you should add to your check-list.
This is the first question whenever an upgrade project comes up. Why take a perfectly good system that works just fine and make a series of amendments? For one, the SQL Server 2016 offers new features, including Dynamic Data Masking, Always Encrypted, Stretch Database, Row Level Security, Automatic soft NUMA, Query Store and Temporal Tables.
Users also get upgrades to features released in other versions, such as In-memory OLTP (online transaction processing), Always on Availability Groups and DBCC CHECKDB.
Old features and tools may not work with your server and in the event of an unfixable incompatibility issue. In cases of failure, the entire server needs to be restored from backup, which is extremely time-consuming with SQL Server, especially those where additional high availability configurations are being used.
Which drives us back to the point that it is advisable to hire a DBA professional who can advise you on what features will likely cause problems along the way. Their expertise on the process ultimately ensures a seamless upgrade that causes the least amount of damage to the client.