diff --git a/docs/FPGA_NETWORK.md b/docs/FPGA_NETWORK.md
index ceaeb5c0..cad5e8d4 100644
--- a/docs/FPGA_NETWORK.md
+++ b/docs/FPGA_NETWORK.md
@@ -18,7 +18,7 @@ encountered such a situation.
 
 ## Switch configuration
 Special care has to be taken for switch operation, given the FPGA core doesn't support auto-negotiation. It is necessary to configure switch port
-to fixed speed (100 Gbit/s or 10 Gbit/s) and to disable auto-negotiation.
+to fixed speed (100 Gbit/s or 10 Gbit/s) and to disable auto-negotiation. It is also necessary to enable jumbo frames (MTU of 9000).
 
 ## Network LEDs
 Each QSFP connector is equipped with green and orange LEDs. These LEDs are connected to Ethernet physical layer status port (rx_status).