How to optimize AllowedIPs "overlapping" routes?

[Omkhar Arasaratnam]

Rather than using the route setup logic in wg-quick, you could
manually set the default gateway for (1) and add a more specific route
for (2) in your route table. iirc (in Linux anyway...) the more
specific route would take higher precedence.

--oa


--oa


On Sat, Apr 22, 2023 at 7:18 AM Johnny Utahh
<mailman-wireguard.com at johnnyutahh.com> wrote:
>
> More discussion here:
>
> https://www.reddit.com/r/WireGuard/comments/12oimvq/how_to_optimize_allowedips_overlapping_routes/
>
> Clearly this is FAQ-ish kind of thing. It was a little hard for me to
> easily find a reference for this kind of stuff. I realize the WireGuard
> project may not consider it to be their responsibility to address such
> things.
>
> ~J
>
> On 2023-04-16 10:06 AM, Johnny Utahh wrote:
> > 1. wg0.conf: AllowedIPs = 0.0.0.0/0, ::0/0 --> higher-latency network
> > 2. wg1.conf: AllowedIPs = 192.168.7.0/24   --> much-lower-latency network
> >
> > When enabling both of the devices/.conf's (listed as 1. and 2. above)
> > concurrently, the #2 route travels over #1 (all starting up via
> > 'wg-quick'). In this scenario I'd prefer #2 routing "bypasses" #1 and
> > retain its (#2's) lower-latency path/network. Can this be done, somehow?
> >
> > I deduce the "route" for #2 changes when concurrently-enabling #1
> > because the #2-ping-latency immediately and dramatically increases to
> > match #1-network's latency (and immediately reverts to #2's lower
> > latency when #1 is disabled). This hurts my #2 network, badly.
> >
> > I'm running/testing the above on macOS v12.6.3 build 21G419,
> > wireguard-go v0.0.20230223. If not on macOS, might this be feasible on
> > Fedora or Ubuntu?
> >
> > I realize this might be a FAQ. I could not find any docs/resources to
> > help after a brief search, so I'm posting here.
> >
> > [I'm not a networking expert, so I may be butchering various
> > terminology, concepts. I apologize in advance for my ignorance.]
> >
> > ~J