You have a QNAP NAS and want to better balance network traffic by trunking two network cards. In addition, you’d like to support failover if a NIC or network cable goes bad or is disconnected.
There are a few ways to enable trunking (sharing two or more NICs to send traffic over a network), including 802.3ad (LACP), but many require special settings on the network switch. For standard switches, you can use balance-alb, which provides better use of two NICs for transmit and receive. With balance-alb, you will get the most benefit if your NAS is talking to more than one server because balance-lab uses some ARP tricks to tie different traffic to each of the NICs. (802.3ad will actually let you fully bond two or more NICs for the fastest possible speed, but it’s more complicated to setup.)
Note: In this example, we’re using a QNAP TS-509 with firmware version 3.8.3.
First, plug in two of the NICs from the QNAP into a GbE switch. If the QNAP has more than two NICs, note that the QNAP does everything in pairs like 1+2, 3+4, 5+6, and never like 1+5 or 2+4.
Second, follow these steps to configure the trunk:
- Log into your QNAP NAS as an admin.
- Click on System Administration->Network.
- Assuming you have a model with a dual NIC, you’ll see something like the following. Notice one IP is set to be static while the other is often left on DHCP. (You should unplug it honestly if it’s not in use.) Now let’s bond these two NIC ports.
- Click on Port Trunking, Settings.
- Then update the settings to use the Trunking Group 1 with the mode as balance-alb.
- Click Apply.
- Now notice the new and improved Ethernet 1+2 setting in the Network screen.