According to the Veeam Backup & Replication Best Practice Guide1, one of the possible ramifications of shortening the backup window to eight hours is that the CPU and memory requirements of the proxies will be increased. This is because:

•The proxies are responsible for retrieving data from the source and sending it to the target. They perform data compression, deduplication, encryption, and other tasks that consume CPU and memory resources.

•To shorten the backup window, the proxies need to process more data in less time, which means they need more CPU cores and memory to handle concurrent tasks and avoid bottlenecks.

•The backup window can also be affected by other factors, such as the network bandwidth, the storage throughput, the backup methods, and the backup settings. Therefore, it is important to consider all these aspects when designing a backup solution.

References: 1: Proxy - Veeam Backup & Replication Best Practice Guide