For large datacenters, there are two primary approaches to cabling servers. The first is to have patch panels in each server rack, and the other is to have switches in each rack. These both present benefits and management topics. For the organizations that are teetering on one way or the other regarding in rack switching, this collection of a few pros and cons each way may help guide the decision process.
Reasons for having switching in server racks include the following:
- -Less risk of running out of ports in that rack. When switches are in a rack, there are more options, including adding a switch to accommodate the needs in that rack. The alternative may mean additional patch panels installed and run back to the core network.
- -Can delegate connectivity requirements. If chosen, server administrators can wire up their own cables to the port that is provided. And in that sense, network teams can have a much smaller responsibility in regard to the cabling from switch port to connecting device. Frequently, server administrators would like this flexibility and would generally accept the responsibility.-Potentially deliver as-needed service. Certain low-priority systems and racks may not need much in terms of connectivity. Simply putting a single fiber run with a GBIC feeding a managed switch providing 100 Mbit/s ports may suffice. It may not be worth the cost of more expensive switches or blade ports in a central patch panel to provide connectivity to lesser important systems.
Reasons against having switches located in server racks include the following:
- -Less risk of tampering. When the network team’s equipment is located in racks that are mostly populated by non-network servers, there is a risk that server administrators will switch ports or move things around.
- -Potential underutilized switches. If switches are placed in each server rack, there is no guarantee that each switch will be utilized completely. Whereas in a central patch panel and switch environment, the entire connectivity footprint can be placed on designated equipment with minimal underutilization.-Less management. Reasons such as power control, risk of someone else tampering with the switch, and more ground to cover with the switching footprint make in-rack switching harder to manage and control.
These are only a few points around the topic of in-rack switching. My goal is not to say which approach is better, as I have not established any criteria to determine which is better. I now am looking for your comments as to why you think in-rack switching is or is not a good way to go. Share your comments below based on what you are currently doing related to this issue.
Rick Vanover is a software strategy specialist for Veeam Software, based in Columbus, Ohio. Rick has years of IT experience and focuses on virtualization, Windows-based server administration, and system hardware.