How to optimize AllowedIPs "overlapping" routes?

How to optimize AllowedIPs "overlapping" routes?

[Johnny Utahh]

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

Re: How to optimize AllowedIPs "overlapping" routes?

[Johnny Utahh]

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

Re: 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@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

Re: How to optimize AllowedIPs "overlapping" routes?

[Tomcsanyi, Domonkos]

The best way to deal with this IMHO in a multi platform way is adding weight or metric to the specific routes, allowing them to be manually prioritized.

Cheers,
Domi


> 22.04.2023 dátummal, 13:25 időpontban Omkhar Arasaratnam <omkhar@gmail.com> írta:
> 
> 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@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