The Perils of Switch-to-Switch-to-Switch Configurations

Connecting multiple switches in series (switch-to-switch-to-switch) can lead to several problems, especially in larger or more complex networks. While such setups might work for small environments, they can introduce significant issues as the number of switches grows. Here are the key perils associated with this practice:

1. Increased Latency and Bottlenecks

Each switch adds a small delay as it processes and forwards data. As more switches are added, latency accumulates, leading to noticeable slowdowns. Bottlenecks can also occur if traffic has to pass through multiple switches, especially if one switch is overloaded or slower than others[1][2].

2. Broadcast Storms

When multiple switches are daisy-chained, the risk of broadcast storms increases. Broadcast traffic, such as ARP or DHCP messages, can propagate across all switches. Without proper containment (like VLANs), the network can become overwhelmed, causing degraded performance or complete outages[3][4].

3. Network Loops and Redundancy Issues

In the absence of Spanning Tree Protocol (STP), network loops can form in a daisy-chained setup. Loops cause packets to circulate endlessly, leading to broadcast storms and potentially bringing down the network. Managed switches often mitigate this through STP, but unmanaged switches lack this feature, making loops a serious concern[5][6].

4. Difficulty in Troubleshooting

As more switches are added, troubleshooting becomes more complex. Identifying the root cause of an issue, such as a faulty switch or port, can take significantly longer. Unmanaged switches, without logging or diagnostic tools, make this process even more challenging[1].

5. Bandwidth Contention

Traffic between switches often flows through a single uplink port. As more devices are connected downstream, all of them share the limited bandwidth of this uplink. This can lead to congestion and slower network performance[3].

6. Limited Redundancy

In a daisy-chain setup, the failure of one switch can disconnect all devices downstream. Without proper redundancy, the entire network’s reliability is compromised[2][4].

Mitigating These Issues

To avoid these pitfalls, consider the following solutions:

• Use a Star Topology: Connect each switch directly to a core switch or router to reduce latency and improve redundancy.
• Enable STP: Ensure Spanning Tree Protocol is enabled on managed switches to prevent network loops[5].
• Upgrade to Managed Switches: Managed switches offer features like VLANs, QoS, and SNMP, which help prevent broadcast storms and improve overall network performance[6].
• Use Link Aggregation: Aggregate links between switches to increase bandwidth and redundancy.

Conclusion

While switch-to-switch-to-switch configurations may work in small environments, they pose significant risks in larger networks. Proper design with redundancy, VLANs, and managed switches is essential to avoid performance degradation and ensure scalability.

References

• Home Network Geek: Managed vs Unmanaged Switches: Which Is Best for a Home Network?.
• FS Community: Unmanaged Switch Basics & FAQs.
• Pacific Radio: Managed vs Unmanaged Switch Guide for Network Pros.
• Cisco Community: Unmanaged Switch Connected to Managed Switch Causing DHCP and Traffic Issues.
• Baeldung: Switches: Managed vs. Unmanaged.
• Cisco Blogs: The Top 5 Reasons to Avoid Unmanaged Switches on Your Machines.