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QManager
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Universal (RM551E & RM520N)

LAN Gateway & Subnet Configuration

Configure local IP addresses, DHCP leases, address pool ranges, and prevent subnet collisions.

4 min read · Updated

LAN Gateway & Subnet Configuration

Configure the internal local network settings for the Ethernet / RGMII port on the modem or router.

QManager RM551E Ethernet status and LAN address screen
RM551E: Check the Ethernet link, limit its speed and set the LAN gateway address.

Gateway IP & Subnet Setup#

In Network > LAN Settings:

  • IPv4 Address: Default 192.168.224.1 for RM551E (on-modem OpenWRT) or 192.168.225.1 for RM520N & RG501 native Linux modems. If the modem sits behind your router's WAN port, keep its LAN subnet different from the router's own LAN subnet to avoid an IP conflict.
  • Subnet Mask: Standard 255.255.255.0 (/24).

DHCP Server & Leases#

  • Start / End IP Range: Assign dynamic pool within your subnet (e.g., 192.168.224.100–192.168.224.250 on RM551E, or 192.168.225.100–192.168.225.250 on RM520N).
  • Lease Time: Default 12 hours (12h).
  • Static Leases: Reserve dedicated IPs for internal servers, access points, and NAS devices based on client MAC address.

Avoiding Subnet Collisions#

Screens in QManager#

QManager RM520N Ethernet status screen
RM520N: Ethernet Status shows the host link state and lets you force a fixed port speed.