RV042 v3 Cable/DSL Load Balancing Issue

[marksbond]

I am attempting to load balance 2 ISP connections:

WAN 1- Comcast Cable 1500 MTU

WAN 2- Verizon DSL 1492 MTU

Both connections come up and load balancing is occuring.

After WAN2 DSL is connected to the RV042, web browsing on LAN devices periodically and randomly times out. This oocurs when accessing varous sites including sights on the LAN such as device web configuration pages for the RV042 and the DSL modem. Repeated browser reload commands will bring the pages up. This happens on devices connected by wire and connected wirelessly to the RV042 via an access point. It looks like what an MTU issue would appear and I've dropped the Cable MTU configuration down to 1492 which doesn't resolve the issue. Summarily it appears that after DSL is connect to WAN2, the RV042 starts to choke on web page routing.

Any thoughts would be appreciated.

[rberber07]

When using double WAN there is always the issue of "sessions", it occurs when using https, once you have been validated with one (WAN) IP address, if your traffic goes out the other the site will complain.

The main point is the word "complain", not a time-out, or any other error, just your session will be invalid.  The fix is to give priority to one WAN for handling such traffic (both http and https).

What you are seeing is a different problem, and my guess is that it is unrelated to the use of double WAN, the main clue for this being that you have the problem even inside your LAN, that traffic doesn't go through the WAN ports.

Usually those problems mean that you have a failure somewhere, the usual way to find out is to look at the network statistics on every device (servers, workstations, switches) looking for errors but statistics on the RV are unreliable (both: Web pages like the port info, and SNMP), the latest firmware has bugs on those statistics or, to be precise, in some of those stats (the LAN traffic through SNMP is fine, both WAN traffics are not; I haven't looked into detail of the switch ports).

Another possibility is that you have too much traffic (enough to make the RV CPU not being able to handle it).  I haven't seen this problem so its just a speculation, in fact the RV CPU is very lightly loaded from what I've seen, but I haven't used the VPN capabilities which probably could put some stress.

[marksbond]

I too feel that the issue is on the LAN side.

Oddly,  it seems that it only occurs after I connect the DSL modem (bridged Westell 7500 w/wireless disabled) to the WAN2 port. After a return to factory default, if I run the network with only the cable modem connected to WAN1, the issue does not occur. Is there anything that you can think of that could explain why connecting a device to a WAN port would affect LAN functionality? Do they share the same switch?

I do know that although the DSL modem is configured in the bridge mode,  it's web configuration page remains accessible at 192.168.1.1 if it is accessed directly from a PC while both are off of the network. This is also the address of the RV042 when accessed from the LAN side.

I did note in another discussion that Network Service Detection should not be enabled on WAN2 as it is a bridged PPPoE connection. I should note that the only devices connected to the LAN when this issue is occurring are a wireless access point with 2 or 3 clients and a PC wired to the RV042.

[rberber07]

marksbond wrote:
Do they share the same switch?

No, the WAN ports are separate from the LAN (switch) ports.

I do know that although the DSL modem is configured in the bridge mode,  it's web configuration page remains accessible at 192.168.1.1 if it is accessed directly from a PC while both are off of the network. This is also the address of the RV042 when accessed from the LAN side.

That could be the problem.  Have you tried changing IP address on the modem?

I have a similar situation, but I haven't enabled the modem in bridge mode.  The modem is used also as AP, so I gave it an address on a different network, disabled DHCP, and connected it from switch to switch on the RV.  Yes, 2 cables from the modem switch to the RV, one to the WAN2 port, another to the switch.  I also gave the modem a second IP, one in the LAN space, that way I can configure and have general access to its Web interface from the LAN.  There's probably a better solution.

I did note in another discussion that Network Service Detection should not be enabled on WAN2 as it is a bridged PPPoE connection. I should note that the only devices connected to the LAN when this issue is occurring are a wireless access point with 2 or 3 clients and a PC wired to the RV042. 

There are differences between modems, some can be accessed when they are in bridge mode, some not.  But sending pings shouldn't work, the RV is configured to connect to a modem and use pppoe to the ISP, no modem IP defined anywhere (from the RV point of view) so there is no way to send a ping when the IP address is unknown.

[marksbond]

Had to jump through some hoops, but I was able to change the IP address of the modem and it appears to have rectified the issue.