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Dual wan anyone get it working with Reliability ?

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Reviving a slightly old thread... I'm sad to see that I'm not the only person disappointed with the dual wan feature.

With everyone in my house working from home these days I decided to get some internet insurance by supplementing my cable with dsl.
I'm in a similar position. Working from home in with a very busy internet connection, the cables to my home were damaged and my DSL service became incredibly unreliable.

I bought a 4G router with the plan of using failover and failback to provide near continuous service on my RT-AC68U but have also been very disappointed. Failback is very important to keep 4G usage under control.

A couple of things caught me out and have helped to stabilise the situation a little:
  • Firstly I completely missed that the WAN page, Internet Connection tab gains the option to switch between the different WAN connection configurations in the WAN Index section. It's obvious when you realise, but I initially missed it
  • Unless Auto Network Detection / WAN Monitoring is configured it only detects loss of link on the network port
  • I had issues with "Your ISPs DHCP does not function correctly" even using Static IP on both ports. It seems this is a known error in the firmware and ASUS is beta testing a fix at the moment
  • When the connection tried to failback was when real problems started. Sometimes it would try to return, decide it had no internet connection and failover again. Sometimes I would end up with the Primary WAN in Cold Standby and the Secondary also not carrying traffic
  • I have found that failover works with identical IP addressing on both WAN connections, or different networks. I have not found a definitive definition of what IP configuration is expected, but I assume different, but I had wondered if identical might help with routing tables or other features converging
  • This post and the following seem to be very relevant. If you set the detection parameters outside of the stated ranges they don't work properly.

I am starting to wonder if the router tries to access to network detection hosts (Ping or DNS) using whichever WAN route is active, and maybe instead of setting up a test to 1.1.1.1 or 8.8.8.8 I need to find an IP address to ping which my ISP router can see, but my standby 4G router cannot. I need to test of my ISP DNS servers are accessible from outside their network. This way it would only detect the primary network returning if it actually does return.

I'm keen to keep trying to get this feature working properly as it "should" be relatively simple if everything worked as intended.
 
with ASUS you can forget it, fail-over and load-balancing just doesn't work reliably, and not only that, but the watchdog will sometimes break your primary WAN (stable) connection, and switch to Secondary WAN after X seconds, whatever you have configured, because of "failed" ICMP reply or DNS lookup (false-positive or false-alarm, however you call it)

If you are having Skype conversation, your call is gone at that point!

I wrote to Asus they should setup watchdog like this:
1. PING (ICMP) layer 3
2. DNS lookup (UDP port 53 - layer 4-5-6-7)
3. HTTP "lookup" with WGET or CURL (layer 7)

that would solve false positives

I am not affiliated with Synology at any level, but I have tested their router RT2600AC and it is THE ONLY device out on the whole SOHO market that actually has working failover and load-balancing! at the moment of writing this!
https://www.synology.com/en-global/products/RT2600ac

you don't have to take my word, simply do a research yourself, read router user guides and check for fail-over / load-balancing configuration options, I have even e-mailed many manufacturers to ask additional questions that have not been answered in user guide, etc.
 
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I looked for the Synology RT2600ac but they are all either unavailable, significantly overpriced, or not available to ship to Canada.

I see that Tomato does multi wan so I'm going to experiment with it on my n66u in between my modems and ac3100. I haven't played with Tomato for years so it should be interesting to see where it is now.

Sent from my SM-G975W using Tapatalk
 
I'm testing a cheap and easy way to get dual WAN without using the Asus implementation.

Here's my new setup using the latest version of FreshTomato on an old router; does anyone see anything in my setup that could cause issues?

Cable modem (bridge mode) -> Tomato router (wan1)
DSL modem (router mode) -> Tomato router (wan2)
Tomato router (multi wan, wan1 primary with failover to wan2, check in 1 minute intervals) -> RT-AC3100 (wan port)

I turned on DMZ mode on the tomato router and assigned it to the RT-AC3100.

Cable modem (when not in bridge mode) is 192.168.0.1
Tomato router is 192.168.1.1
RT-AC3100 is 192.168.2.1
DSL modem is 192.168.3.1

It sucks that I had to add an additional point of failure to my network, but so far it is working well with no noticeable speed decrease

I need to replace the cable amplifier in my house so when that is disconnected I'll see how well the fallover and fallback works.

Comments, criticisms, and improvement suggestions are welcome!

(This may not be the correct thread to have this discussion, I can open a new thread if anyone objects with using this one)

Sent from my SM-G975W using Tapatalk
 
I am not affiliated with Synology at any level, but I have tested their router RT2600AC and it is THE ONLY device out on the whole SOHO market that actually has working failover and load-balancing! at the moment of writing this!
https://www.synology.com/en-global/products/RT2600ac

Do you or anyone else have any experience of the Synology MR2200ac for failover to 3G/4g? It’s a lot cheaper than the 2600 and seems to run the same firmware. https://www.synology.com/en-uk/products/MR2200ac
 
Hello,

I’m just reporting that I actually had success with WAN failover and failback working for me. In my case, the primary WAN connection (Comcast) had an outage and my secondary connection (USB Cellular modem with T-Mobile service) was activated after 1 minute. Just as configured. Once the Comcast service was restored, it failed back after 3 minutes to the primary WAN connection. Again, just as I configured. The router is a RT-1900P. I did configure it to use the IP address of 8.8.8.8 as the ping target to determine if there’s an outage. No DNS query configured. The firmware is Merlin 384.16. Since this is my only experience so far with an unexpected outage with this configuration, I can’t claim it’s reliable. I can only say it’s worked at least once so far. I also noticed that Asus claims to only support Dual WAN failover on only certain router models which the 1900P is one of (https://www.asus.com/support/FAQ/1037368/). I wonder if that may be part of the issue some are experiencing with this?
 
I'm also checking back in to report that I upgraded my RT-AC68U (not listed as supported) to a RT-AX88U (listed as supported) and, following some problems with my internet line, I can confirm that I also have Dual WAN Failover & Failback working well for me using a 4G router on Ethernet 1 as the secondary connection. I'm also just using ping for my failure detection.

I configured Dual WAN in a hurry when my primary line became unstable as I was configuring features one at a time from the base configuration. I discovered that Dual WAN does not work with the OpenVPN server running - the link failure detection was totally messed up, but simply flicking the VPN server switch off in the router GUI stabilised Dual WAN for me.
 
Running a dual WAN setup failover & failback on an rt-ac86U. Primary WAN coming from an ONT, secondary WAN coming from a separate ONT. Using Ping for connection status. Except for the occasional “your ISP DHCP does not function correctly” issue, it’s working fine.
 
I'm also checking back in to report that I upgraded my RT-AC68U (not listed as supported) to a RT-AX88U (listed as supported) and, following some problems with my internet line, I can confirm that I also have Dual WAN Failover & Failback working well for me using a 4G router on Ethernet 1 as the secondary connection. I'm also just using ping for my failure detection.

I configured Dual WAN in a hurry when my primary line became unstable as I was configuring features one at a time from the base configuration. I discovered that Dual WAN does not work with the OpenVPN server running - the link failure detection was totally messed up, but simply flicking the VPN server switch off in the router GUI stabilised Dual WAN for me.
I obviously tempted fate as my internet went down yesterday and Dual WAN failed to cut over. It recognised that my primary circuit was down but the secondary stayed in Hot Standby.

I'm currently running my RT-AX88U on Merlin 384.18_beta1 and can't help wondering if it's related to the "your ISP DHCP does not function correctly" issues. I was running with static IP but think that problem may indicate a bigger issue within the router logic. I believe the ISP DHCP issue is fixed in a later Asus release so might need to wait until 384.19 before I try again.

Frustrating :(
 
A further update - I realised that when I'd previously had Dual WAN Failover working I had been testing the stock Asus 384_9107 firmware. Merlin 384.19_alpha1 is just out for the RT-AX88U including later GPL with SDK and binary blobs from 384_9107.

I just upgraded and can confirm that the Dual WAN failover and failback is working like a dream. I still see the ISP DHCP message occasionally so have switched static IP as I'm using local upstream routers on both legs, but I don't think that affects the link detection where I'd previously had the problems.
 
If it is possible to switch WAN from a shell a simple scheduled task can solve this for any model any firmware.

For example you can open a restfull connection, when internet fails this connection and the program exits, you conduct tests to see if the exit is related to a failure and flip WAN when needed, restart connection.
 
I've had many problems with Dual WAN failover as well, and I am in the middle of investigating how to make it work in a predictable way without requiring constant monitoring by the end user. Clearly the ASUS failover/failback code needs to be thought out much more carefully, but I hope this post will offer a few hints that might work for some.

First of all, I think it's best to avoid doing a DNS Query Network Monitoring because of all the DNS caching that might return results even if there is no connection. I suggest doing ONLY ping-based network monitoring for now to an outside server. I use 8.8.8.8, and am experimenting with pinging to the (primary) WAN device gateway IP (say 192.168.0.1, which may be problematic if the secondary's gateway IP is 192.168.1.1)

I suspect part of the problem is that the WAN devices may be showing a gateway to the ASUS router, and the ASUS code is simply using that as a pre-condition before the failover mechanism to kick in. For now WAN failover/failback seems to be working if I put the WAN devices into bridge mode. Of course that won't be a solution for everyone.

Also it's really important to understand very well your WAN devices, especially how long it takes for each one to establish connection, i.e., from a cold boot, as a way of setting the number of ping attempts and interval between each. I'd connect one laptop to the LAN port of each WAN device and observe how long it takes to get an IP address in the worst case (i.e., from a cold boot). All of that will tell you how many retries, and how many seconds apart you need for the failover and failback.

I am running stock firmware v. 3.0.0.4.382_52272 on an ASUS RT-N66U

Also, it's not clear to me what happens if you are using Load Balance mode instead of Failover/Failback. I've observed that you may be getting a type of failover for free, although I am still not clear if/how failback works.
 
Sorry to revive an old post but I wrote a solution to this problem, check it out here.

 

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