Making sure that your SQL server is protected against unexpected outages and unplanned downtime is important. Achieving this is not necessarily simple, but it helps to have effective backup strategies in place to mitigate the worst of the potential financial damage.
With that in mind, here are some steps to take so that your own SQL server is as resilient as possible in the face of common causes of downtime.
If you are making use of the best SQL Server monitoring tools, you should have a good handle on the status of your server from moment to moment, as well as understanding its size, usage metrics, and any bottlenecks that exist.
Those operating smaller servers may choose to carry out a full backup at regular interface, giving you an exact copy of all data and making it possible to restore everything in the event of an outage or loss.
Another issue to consider in the case of a full backup for your server is that this will only provide a snapshot of the data stored on it at the time that the process was initiated; any additions or alterations which have taken place since then will be lost if there is an outage and you wish to restore from this prior point. Because of this, you may not find that scheduling full backups at regular intervals offers you the kind of resilience you require for mission-critical data.
The potential for data loss resulting from a full backup strategy can be mitigated if you choose a daily backup schedule, although again, this may only make sense for SQL servers of smaller sizes. It all comes down to using the tools available to you to make the right decision for your circumstances.
In the case that you are using the best-dedicated server hosting for a database that is packed with endless gigabytes of information, a differential backup strategy will make more sense.
In this case, rather than safeguarding the entire contents of the server with each backup, only the information which has altered in the interim between backups will be captured in the snapshot. In combination with less frequent full backups, a differential strategy can be useful and more efficient when the time for restoration arrives.
Many admins choose to plot in differential backups so that they occur when the server usage is at its lowest levels, meaning that processes will not get held up or interrupted at inconvenient moments.
Of course, if your server is not being written to frequently, and instead the data stored on it is being read but not altered in any way, a daily or even hourly differential backup strategy may be overkill, and could be more disruptive than helpful. This is where drilling into the analytics can be your best decision-making tool once again.
If you cannot tolerate any kind of data loss in the event of an SQL server outage, then opting to include transaction log backups as part of your strategy will be worthwhile.
This enables the option of restoring a database not just with all the information intact, but also to a specific state saved at a given moment when the latest transaction log was created.
You can expect that a combination of a full backup conducted at lengthier intervals, alongside a differential backup and a transaction log backup, will cover as many bases as possible and account for even the most serious issues that might afflict your main SQL server.
Of course, in all of this, it is worth mentioning that any form of backup strategy will involve the investment of both time and money in order to put it into action. This can put some businesses off the idea of getting started with this process, but failing to appreciate the risks that such complacency invites is a real issue. The cost of having a continuity plan in place is not insignificant, but the alternative is finding that you cannot cope with the expenses that mount up when disaster strikes, especially in our IT-driven age.
Depending on the SQL server platform you pick, you may have access to pre-built data backup and recovery solutions that can make life easier.
For example, SQL Server from Microsoft has three distinct recovery models; simple, full, and bulk-logged. The names are fairly self-explanatory, especially for simple and full models, with the bulk-logged model being well suited to databases which see sizable transactions take place on a predictable schedule.
For this reason, you might consider that premium SQL platforms are more desirable from a backup and recovery perspective than their open-source counterparts. This may be accurate depending on your circumstances, but with so many excellent third-party backup options out there, it is certainly not a limiting factor that should cause you to immediately change platforms.
One aspect of your SQL server backup strategy, which deserves discussion, is the need to ensure that you also consider the scale of the data loss and downtime that your organization can handle. This is all part of appreciating that no backup strategy is completely bulletproof and that when an outage occurs or an unforeseen issue arises, all recovery processes will take time to complete and involve certain compromises.
This will hold sway not only over the route you take to protect your data, but also the amount of capital you are willing to commit to formulating and maintaining a strategy in the first place. Establishing tolerances for data loss and downtime will help you to sell your ideas to the people in control of the purse strings.