xmg1915-18ep. WOL of connected devices

danielpfeiffer

I recently replaced a Cisco switch by the xmg1915-18ep, Nebula managed.

Servers configured for WOL cannot get started while connected to the xmg1915-18ep switch as its showing the ports as not connected when servers are off.

Connecting the lan cables back to the Cisco, (even when servers are off at that time) the ports show connectivity and the servers can get powered on by WOL.

Is there any port setting avoiding WOL of connected devices? The servers port speeds fall back to 10/100 mbs speed. Never experienced such issue before.
According to the documentation, Nebula On turns green ethernet off.

Any ideas?

Zyxel_Melen

Hi @danielpfeiffer

This behavior is related to a hardware negotiation characteristic of the XMG1915 series (including your XMG1915-18EP).

The Root Cause

The ports on the XMG1915 series are Multi-Gigabit ports that support 100 Mbps, 1 Gbps, and 2.5 Gbps speeds. They do not support 10 Mbps connections.

By default, many server and PC Network Interface Cards (NICs) are configured to drop their link speed down to 10 Mbps when the system is powered off or in standby to minimize power consumption. Because the XMG1915 cannot negotiate down to 10 Mbps, the link drops entirely (showing as disconnected on the switch), which prevents the Magic Packet from reaching the NIC. Your previous Cisco switch likely supported 10 Mbps, allowing the link to stay active.

You need to change the client's WOL behavior.

• Adjust the NIC's WOL speed (Windows Server/Windows):
  • Go to Device Manager > Network adapters, right-click your network card, and select Properties.
  • Under the Advanced tab, look for a property named WOL & Shutdown Link Speed (or similar, depending on the driver).
  • Change its value from the default (often "10 Mbps First") to "100 Mbps First" or "Not Speed Down".
• Linux Environment (if applicable):
  • If your servers run Linux (e.g., Debian, Ubuntu), check if your specific NIC driver supports maintaining the link speed during halt. Some enterprise Linux drivers may require disabling advanced energy-saving states (ethtool configurations) to prevent the NIC from dropping to 10 Mbps.