Using two residential broadband connections

Hello

I've got two residential broadband connections to my house, BT (55Mbps download) with a Smart Hub 2 and VirginMedia with a Hub 3 (108Mbps download).

BT support IPv6 and have a slightly more stable ping time. VM are IPv4 only and have a generally lower but more jittery ping time.

Are there any helpful, simple and/or reliable ways to split traffic between the two connections? I'd like to prefer VM for streaming and BT for work conference calling, and have automatic failover if one connection is broken.

I've already got ethernet, switches and a spare Raspberry Pi - or maybe there are better options?

I currently have an "accidental" split of IPv4 traffic via VM and IPv6 traffic via BT. I was thinking that if I set up a DHCP server on the network then I could manage IP configurations with a bit more precision.

Many, many ways to skin a cat. Effectively you want a router.

If you want to bond the connection using a Pi, have a read of this recent thread:

https://forums.thinkbroadband.com/fibre/f/4674200-co...

Thanks - looks like an answer is likely in that thread. Draytek and Ubiquiti multi-WAN routers seem like the options offered.

I'm not looking to "bond" the links, but spreading load across them and failing over should be easy.

I don't want to use a Pi to route data, I was considering running a DHCP+DNS server to configure each client to use the most appropriate default and secondary gateway. I'll also look at the multi-WAN router options.

Does the fact that only one of the ISPs offer IPv6 make things interesting? Maybe my best option is to find a way to disable that on the network.

Edited by deleted (Sun 07-Mar-21 21:00:15)

first most basic option use the BT router as the main router then connect the VM router to the same network with DHCP option disabled, i have no idea why IPV6 is a consideration on a small LAN

you could then set the gateway on the devices to use the VM router, you could also so use routing to direct traffic if the BT router supports it.

second option is a multi LAN router this will give you the fail over setting up the routing could be fun if you are not network savvy, mikrotik router would do what you require but they are not user friendly draytek can load balance and support fail over ect

if you have suitable hardware then pfsence could also be an option

IPv6 is a consideration simply because:
(a) it already exists in the OPs setup originating from one of the ISPs and
(b) the default behaviour of client OSes and applications effectively prefer IPv6 where available (or responds first), leading to BT being the primary connection more by accident than by conscious choice, and the OP wants to have more active control over the split.

In other words, even if the OP does nothing, it is already a factor in the routing.

btw in response to the original Q, DHCP isn't really intended distribute information about a second gateway on the same network.
The most that DHCP can do are options for classless static routes, which in effect provide advisory routes based on destination IP networks. In modern times this is less relevant when content is spread around CDNs because the option does not know anything about URLs, only IPs, and I say advisory because most client OSes now ignore this option. It was mainly a historical range of Windows OSes which implemented it.
The only routing information all clients will respect from DHCP is the single default gateway.

A dual-WAN router is still the way to go because all LAN traffic then passes through that point to make routing decisions without each client device needing to know about the multiple ISPs.
On that score, even though the OP already has a Pi, the architecture of how its network interface(s) attach to system buses is not suited to this application, though people do have some success using it for local DNS / filtering or proxy roles.

On the topic of disabling IPv6, there is a tendency to turn it off for the wrong reasons, such as not understanding it, and with a dual-WAN router, the routing decisions can be made dynamically based on latency, PING loss, throughput, protocol and a range of other factors without resorting to blunt / brute-forcing methods.

pfSense is indeed ideally suited to this as the features for WAN failover or balancing are of long-standing built-in rather than an afterthought, and fully managed from the web UI. Although people may find the (Netgate) appliance cost off-putting unless they have suitable spare hardware around, the hardware and licencing costs of more commercial offerings to enable equivalent features can rapidly outstrip the cost of pfSense over the lifetime of the boxes.

While Ubiquiti Edgerouters can also do this and at lower cost, having experience with both the latter has quirks especially if wanting to maintain the hardware offloading (acceleration) of flows used to achieve the headline throughput,, so you have to pay more attention to which features you combine, and know how to manage them from the CLI, where more advanced configurations are realised.

Draytek (Vigor) are ok-ish but returning to it to setup a new model recently was shocked to find so many basic changes still requiring a reboot with an outage; the UI and performance has evolved slowly compared to where it was 10+ years ago and most of the interfaces have fixed assignments (in terms of what can be mapped as a WAN or DMZ port vs the LAN ports).
IMO it is still targeting the "all-in-one-box solution" market and you have to pay close attention to the throughput specs when firewall/NAT/VPN are active compared with just routing for model selection.

Edited by prlzx (Mon 08-Mar-21 02:09:11)

Thanks @copex, @prlzx

One enabled DHCP server for my default route, and then a static config of primary and secondary gateway on a couple of machines was where I was going until I noticed that the IPv6 traffic is routed independently of that. For now, I'm just letting the IPv4/IPv6 split determine the balance of traffic on each connection.

In reply to a post by prlzx:

The only routing information all clients will respect from DHCP is the single default gateway.

This was the info I needed to know - thanks, that saves me some time learning by myself.

So, I want a router. I do not think it will need to run a firewall or NAT, I plan that will continue to be handled by the BT Smart Hub 2 and the VM Hub 3.0

DiY Options:
- Build my own router and run pfsense
- Build my own router and run OPNsense?

What would be a suitable kit to build this on? Searching "bare bones" at scan.co.uk I see mostly single LAN motherboards that are more expensive than the dedicated options.

Dedicated Options:
- A NetGate SG-1100 wth pfSense (£143+VAT)
- MikroTIK custom hardware (? from £53+VAT; I'm not sure if hEX models are good for dual WAN)
- TP-Link custom hardware (I like the look of Omada SDN stuff, £140, or cheaper options)
- Ubiquiti (~£50)
- Draytek (?)

Thanks for the opinions you already shared - I'm leaning toward a MikroTIK if I find stock, or perhaps the TP-Link if I find out more about their SDN setup. (Because, in the future I'd consider Omada access points too)

Edited by deleted (Mon 08-Mar-21 17:04:52)

In reply to a post by busywait:

…
So, I want a router. I do not think it will need to run a firewall or NAT, I plan that will continue to be handled by the BT Smart Hub 2 and the VM Hub 3.0
…

This is certainly an option, but note that the VM Hub at least can be put into cable modem mode which simplifies the administration and can pass the public IP to the inner router via DHCP.

For the DSL line we have previously used Draytek Vigor 130 modems combined with pfSense (but same would appy for other ethernet-style multi-WAN router). Again this results in the public IP appearing on the inner router (this time by configuring the broadband credentials as a PPPoE interface). Ideally this means most LAN, DNS, firewall and port-forwarding can be configured in one place.

The budget option would be something like an EdgeRouter ER-X where the ports can be assigned to WAN or LAN and act as switched ports or independent interfaces, run one of the multi-WAN wizards during setup, then see if you need to tweak that. However in production I have only deployed EdgeRouter with static routing and/or OSPF so I could not vouch for the specifics.

For EdgeRouter or pfSense there is the cost factor of Wi-Fi needing to be on separate access point(s) (or a re-purposed router) to provide connections to the same LAN.

For Draytek you could select from any of the multi-WAN models that support 2 ethernet-based WANs or those with integrated DSL for one of the two WANs which would allow for the option of eliminating the BT Hub (or using that just as a second WI-Fi access point with built-in switch).

For sizing your achievable WAN throughput for each connection doesn't necessarily demand a high spec router so I think you are on the right track with some of the hardware you are considering.

Edited by prlzx (Mon 08-Mar-21 09:20:43)

I've been running with Draytek routers for a few years now and their multi-WAN load-balancing feature.

All the important WFH stuff goes over our Zen FTTC and all the home/play/streaming stuff goes over Virgin.
With the auto-failover for all traffic if the other connection drops.

In reply to a post by busywait:

So, I want a router. I do not think it will need to run a firewall or NAT, I plan that will continue to be handled by the BT Smart Hub 2 and the VM Hub 3.0

DiY Options:
- Build my own router and run pfsense
- Build my own router and run OPNsense?


What would be a suitable kit to build this on?

You have been given the best answer. OMR on a Raspberry Pi.
OK, it also needs a VPN server at the internet end, but it's a vastly better solution as well as being cheaper.

Thanks @hoopla.

For OMR I guess I'd need to pay a regular subscription for the VPN? It reminds me a little bit of "RAID" for redundancy.

I see advantages, but at the expense of latency and monthly cost perhaps?
.