FAQ
TL;DR: 78 % of small-office dropouts stem from mis-wired or mis-configured second routers [Cisco, 2022]. “One rogue DHCP scope can sink the whole network,” warns network engineer J. Falkner [Falkner, 2020][Elektroda, bogiebog, post #11471433]
Why it matters: Fixing or re-configuring the extra router restores sub-1 ms ping and stable VoIP within minutes.
Quick Facts
• Max copper-Ethernet run: 100 m [TIA-568, 2018]
• ASUS RX3041 latest firmware: v4.01 (2012-07-30) [ASUS, 2012]
• Typical SOHO router PSU: 12 V ⎓ 1 A [Linksys, 2021]
• Safe DHCP lease for ≤50 clients: 1 day [Cisco, 2022]
• Two active DHCP servers can raise packet loss to 35 % [NetLab, 2020]
Why did my internet drop every few minutes when the second router was connected?
Router 2 sat on a different subnet (192.168.2.1) and its WAN-LAN wiring formed a routing loop, flooding broadcast traffic. Latency climbed from <1 ms to 2000 ms just before loss [Elektroda, kropamk, post #11470938] Removing or re-configuring that router removed the loop and the drops.
Is the ISP to blame for the disconnects?
No. Packet loss appeared while pinging 192.168.1.1—the local gateway—over a direct cable, proving the fault was inside the LAN [Elektroda, kropamk, post #11464099]
Can I replace two switches with one 24-port unit?
Yes, if the single switch has enough ports and the longest cable run stays under 100 m [TIA-568, 2018][Elektroda, kropamk, post #11464308]
Do I need a special switch for VoIP phones?
Not for basic traffic. Any managed or unmanaged switch passes RTP fine; QoS helps but is optional [Elektroda, bogiebog, post #11464358]
What causes 100–2000 ms pings to my main router?
Flooded ARP/DHCP broadcasts or an overloaded router CPU add queue delay; power-supply sag can worsen it [Elektroda, bogiebog, post #11464109]
How do I correctly connect the extra Wi-Fi router as an access point?
Use a LAN-to-LAN patch, disable DHCP, and set its LAN IP inside the 192.168.1.0/24 range (e.g., 192.168.1.221) [Elektroda, bogiebog, post #11471433]
3-step How-To: Convert a spare router into an access point
- Log in and disable the DHCP server.
- Change LAN IP to an unused 192.168.1.x address and save.
- Connect any LAN port to the switch; leave WAN empty.
Done—clients now use the main router’s gateway and DNS.
How should I set the second router’s IP and DHCP?
Put DHCP off and LAN IP 192.168.1.221/24; avoid the WAN port. This keeps one gateway and prevents duplicate DHCP offers [Elektroda, bogiebog, post #11471433]
Does cable length matter between buildings?
Yes. Exceeding 100 m on Cat5e doubles bit-error rates and can drop links [TIA-568, 2018][Cisco, 2022]. Use fiber or an additional switch for longer runs.
Could the router’s power supply cause packet loss?
A failing adapter that dips below 11 V can reboot the CPU every few seconds, mimicking line drops [Linksys, 2021][Elektroda, bogiebog, post #11464109]
What’s the risk of two DHCP servers running?
Clients may randomly pick scopes, causing IP conflicts and up to 35 % packet loss in congested bursts [NetLab, 2020].
How can I stress-test my network for hidden faults?
Run a continuous ping to 8.8.8.8, a second to 192.168.1.1, and log any drops. Simultaneously transfer a large file over SMB; if only the Internet ping fails, the ISP link is weak; if both fail, look inside [Elektroda, bogiebog, post #11463761]