Strange wireguard speed on ax lite

Nikalia · July 27, 2025, 8:56am

hi, i have a strange problem,

have mikrotik ax lite, and connect via wireguard to another host(port speed of another host is limited to 100 Mbit),

and here is the speed test on aks lite shows changing speed, unstable

Summary

on ax lite i have two different internet providers, both are the same pppoe, and this problem is only with provider #1, with provider #2 there is no problem,

but, i tried to replace ax lite with chr, and connect from the first provider, and there is no problem

Summary

i.e. the problem is only on ax lite and provider 1

any ideas?

Nikalia · July 27, 2025, 9:04am

the problem manifests itself in both directions, on transmission and reception,

but if for example I limit the test to 50M, it works stably..

Summary

jaclaz · July 27, 2025, 9:27am

I think that bandwidth test is not only a bandwidth test but also a test for the CPU, or anyway for the router hardware performance.

So a powerful machine will have a constant output (as the CPU will only minimally used), while a less powerful device will have peaks and hollows following the CPU usage.

The usual recommendation is to run iperf tests between two PC’s (or however the actually used “final” devices) at either end of the tunnel to assess the actual throughput.

Nikalia · July 27, 2025, 9:37am

the problem is not performance ax lite, 100 Mbit is only a little more than half of the possible speed for this router, especially since it does not appear with provider #2(wan2)

holvoetn · July 27, 2025, 10:26am

I am not sure I fully understand the way you are testing …
Are you saying you can reach 200Mb using ISP2 ? Using BTEST on the AX Lite itself ? I don’t think that’s possible.
Or you are testing in another way both times ?

Going through AX Lite with Wireguard tunnel (iperf stations on separate devices), I can reach about 200Mb using TCP.
Testing from AX Lite using btest, those performances drop substantially (as already explained by jaclaz).

Can you make a drawing how your test setup is, both for ISP1 and ISP2 ?
Also indicate which ISP speeds is available for both setups.

Nikalia · July 27, 2025, 1:00pm

ok, i’ll try to translate it into English at the level of home pets,

i have AX Lite and there are two cables,

one is a wire from provider #1, where the internet is via PPPoE and the speed is 500 Mbit,
the second wire is from provider #2, where the internet is via PPPoE and the speed is 100 Mbit,

I take an internet cable and insert it into the ether1 and test the speed, then I pull it out and insert a second cable and test the speed again…

since the host I’m testing with is limited to only 100 Mbps, the maximum speed I can get is 100 Mbps

I tried replacing the AX Lite with a CHR and there was no such problem on it,

now I want to try the same thing with hEX Refresh.. I’ll write back when I check. and maybe I’ll try to downgrade or upgrade the firmware on the AX Lite, maybe something is broken again like it was on my AX2, hEX Refresh.. I’m not surprised

a little later,
hmm interesting
same thing,

Summary

configuration

Summary

[admin@MikroTik] > /export 
# 2025-07-27 16:37:03 by RouterOS 7.19.3
# software id = 3RBJ-II1Z
#
# model = E50UG
# serial number = 
/interface wireguard
add listen-port=13244 mtu=1420 name=wireguard1
/interface wireguard peers
add allowed-address=0.0.0.0/0 endpoint-address=1.2.3.4 endpoint-port=13231 interface=wireguard1 \
    name=peer1 persistent-keepalive=20s public-key="12345678"
/ip address
add address=10.0.1.6 interface=wireguard1 network=10.0.1.1
/ip dhcp-client
add default-route-tables=main interface=ether3
/system clock
set time-zone-name=Europe/Moscow

holvoetn · July 27, 2025, 1:46pm

First of all, you can scale down the tone a bit.
You came here for help with your problem. We are not required to help you, we do this on our free time.
This is a USER forum, you see …

Secondly, English is not my native language (and from what I can see, it’s not yours either), so I might not get all nuances from the first look at things but as far as I can see, this is the first time you mention something about a Hex Refresh here.

Thirdly, I still don’t see WHERE THE PROBLEM is ??
You have a host limited to 100Mbps and you are surprised that Wireguard only gives you 75Mbps ? Is that the problem ?

Newsflash: it’s normal !
You’re limited to 100Mbps on one end. Guess where the bottle-neck is then ?
Wireguard also needs some overhead to encrypt the communication so you will loose net throughput making the end-result lower then 100Mbps. And 75Mbps sounds about right.

If this is not your problem, please describe exactly what you EXPECT to see versus what you actually see.

Nikalia · July 27, 2025, 1:51pm

sorry if i offended you, i didn’t mean to

as i already added above, i reproduced the same problem, on hex refresh, then i downgraded it to 7.15.3 and the problem remained, then i upgraded it to 7.20beta6 and the problem seems to have been solved, i need to check on ax lite, i’ll write a little later

BartoszP · July 27, 2025, 1:55pm

Pets, kids & adults learn by experience.

holvoetn · July 27, 2025, 2:03pm

Hex Refresh ether 1 speed issue was solved with 7.20beta5.
On AX Lite that issue is non-existant.

I still don’t see WHAT the problem is …

Nikalia · July 27, 2025, 2:10pm

i use ether3…

good news, for hex refresh it’s fixed in 7.20beta6
bad news, for ax lite it’s still broken

I’ll create a support ticket, but honestly I’m a bit disappointed and skeptical, anyway, I hope if someone encounters this problem, they’ll have some starting point

thanks!

hex_refresh_7_20beta6

Summary