How much bandwidth do I need for offsite data backups?

by: Robin Remines

Deciding how much bandwidth is required for your offsite data backups requires a review of your Recovery Point Objective (RPO), how often you want to send data offsite, and how much of your production bandwidth you are willing to commit to your data off-siting operation. We’ve prepared this quick overview to walk you through this process.

Common Strategies

A common practice is to use 100% of production bandwidth during non-business hours to offsite the complete days data change. This allows for greater bandwidth utilization and has no effect on your bandwidth availability during business hours. On the other hand, should you have a failure through the course of business in a given day, your last backup point would have been the close of business on the previous day meaning every data change that occurred on the day of the failure would not be included in your offsite backups. Another drawback to the nightly backup method is the longer the interval of time between your backups, the larger the backup file will be, requiring more time and/or bandwidth to complete the offsite backup operation.

Estimating your offsite data requirements

Another method of sending backups off site is to commit a portion of your production bandwidth to backups that occur throughout the day. How much bandwidth and how much data you are sending off site will determine what the appropriate time interval is. There are many advantages to this method, including more recent RPOs, smaller backup files, and smaller utilization of bandwidth. Some disadvantages are; bandwidth usage during business hours and a more frequent backup operation can put undue strain on your databases while they are expected to be performing production operations.

Backup Frequency

Whatever you decide with regard to backup frequency, you can estimate the size of the back-up file for that given time period, then estimate how long it will take to offsite that amount of data using the amount of bandwidth you have made available to the backup operation. There are many online file transfer speed calculators available online. Here is a link to a straightforward version:

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