As mentioned in previous reviews, I'm an advocate for Dual WAN connections for any organization that depends on email and the Internet to conduct business. The RV042 has Dual WAN ports, with the option of configuring the second port for a connection to an alternate ISP in either a failover or load-balancing mode, or configuring that port for a DMZ network.
The RV042's two WAN ports support Ethernet or PPPoE connections. My primary WAN connection is a Telco PPPoE connection. I used a second router to simulate an external WAN connection. I configured the secondary WAN connection as a standard Ethernet connection and to obtain an IP address.
For Dual WAN, you can configure the RV042 in Smart Link Backup or Load Balance Modes. The Smart Link Backup mode will utilize one WAN connection exclusively, only switching to the second WAN connection if the first fails. Further, the RV042 provides configurations for Network Service Detection, which instructs the RV042 to test the active WAN interface by pinging a remote server or IP. In the event that Layer 2 on an interface is up, but Network Service Detection fails, this should trigger a WAN failover.
Interestingly, while in Smart Link mode, the RV042 does not acquire or display an IP address on its secondary WAN port. Figure 9 shows the RV042 with WAN1 active and WAN2 in standby with the RV042 configured in Smart Link mode. Notice that the WAN1 port has a public IP (74.72.XX.XX) from my ISP, while there is no IP assigned to WAN2, even though the port is green as shown in the graphical display.
Figure 9: Dual WAN port status in Smart Link mode
To test Dual WAN Rollover, I set up a continuous ping to a public website, disconnected the ISP cable from the WAN1 port, and plugged it into the secondary router. Upon disconnecting the ISP cable from the WAN1 port, I expected to see the WAN1 interface go down, and it to switch over to the WAN2 interface.
This worked as expected, with Internet connectivity, as verified by the continuous ping, restoring on average in 45 seconds. In recent tests of another Dual WAN router, the Netgear FVS124G, failover took nearly 3 minutes, so this was a relatively impressive result.
The Linksys disappointed when I restored the ISP connection to the WAN1 port, however. This should have resulted in the RV042 switching back to the WAN1 connection. Unfortunately, the only way it would connect back to the WAN1 connection was if I manually clicked the Connect button next to the interface. I'm not sure if this is due to the login requirement of the PPPoE connection or a failure of the Network Service Detection functionality. Nevertheless, failover is only half the battle. Fallback is equally important, and this didn't seem to work as expected.
The Load Balance Mode increases bandwidth, as well as configuration options for utilizing both links. As you can see in Figure 10, Load Balancing requires configuring the bandwidth capabilities of both links, as well as binding various protocols and flows to specific WAN interfaces as required.
Figure 10: Dual WAN links in Load Balance mode
The Dual WAN/DMZ port can also be configured with the DMZ option. This option makes sense when there are one or more devices with pubic IP addresses that you want outside the firewall, but retain access to the Internet.
There are six RJ45 ports on the back of the RV042. Four are LAN ports, the other two are WAN/DMZ ports. The RV042 provides means for viewing Layer 2 status on all six ports, reviewing statistics on the use of each port, and configuring options for each port.
As shown in Figure 11, there is a graphical display of the RV042's six ports in the System Summary page. If a port is green, it indicates that the port has a good Layer 2 connection. Of course, Layer 2 doesn't mean data will pass; a Layer 3 address still needs to be assigned. I deactivated the WAN2/DMZ port in the figure to highlight the usefulness of this display.
Figure 11: System Summary showing port status
To see if the port is passing data, the Port Management-Port Status submenu displays statistics on packets, bytes, and errors received and transmitted. What I find the most useful is the per port configuration options. Linksys provides a menu for setting each port's speed, duplex setting, priority, and on/off status.
The Priority option is a simple QoS implementation, telling the RV042 to prioritize the traffic on a specific port. In Figure 12, I've configured port 3's traffic (which is where I've connected a VOIP device) to have a higher priority than the other ports.