Hi,
I searched all available forum posts and the internet to be sure I was not asking a question that was already answered so I hope i'm not wasting your time reading this.
I have just moved and changed ISP. My new ISP (telus) is charging me for 1.5Gbps over fibre. My setup looks like this:
Fiber to the home (tested today by technician, integrity seems good
to
ISP "fiber modem" (I seems to act as a modem and router with some firewall capabilities. I have my own firewall after it so I would love for it to be a modem and nothing else but it doesn't seem to present me with such option, eh...)
Model: NH20A
Firmware Version: v1.18.07 build02
Boot Code Version: 0.00.01
Hardware Version: R01
This device has 4 RJ45 1Gbit/s ports and 1x RJ45 "10Gbit/s" port.
I connected a cat6cable (and tested other cat6 and cat5e short cables) from that 10Gbit/s port to my
DEC750 igb0 (and tried igb1 aswell) port which advertises
100/1000/2500Mbps capabilities.
Unfortunately, I am unable to get more than 1Gbits/s link speed
ifconfig igb0
igb0: flags=1008843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST,LOWER_UP> metric 0 mtu 1500
description: WAN (wan)
options=4800028<VLAN_MTU,JUMBO_MTU,HWSTATS,MEXTPG>
ether f4:90:ea:00:bc:06
inet 192.168.1.64 netmask 0xffffff00 broadcast 192.168.1.255
media: Ethernet autoselect (1000baseT <full-duplex>)
status: active
nd6 options=29<PERFORMNUD,IFDISABLED,AUTO_LINKLOCAL>
My DEC750 is running opnsense Version 26.1.10.
The GUI under Interfaces>Overview shows me this
https://imgur.com/a/1ppr9wY
and this
https://imgur.com/TDpsU2o
(images also attached)
while the details view shows me this
Flags up
broadcast
running
simplex
multicast
lower_up
Capabilities rxcsum
txcsum
vlan_mtu
vlan_hwtagging
jumbo_mtu
vlan_hwcsum
tso4
tso6
lro
wol_ucast
wol_mcast
wol_magic
vlan_hwfilter
vlan_hwtso
netmap
rxcsum_ipv6
txcsum_ipv6
hwstats
mextpg
Options vlan_mtu
jumbo_mtu
hwstats
mextpg
MAC Address **:**:**:**:**:**(censored) - Deciso B.V.
Supported Media autoselect
1000baseT
1000baseT full-duplex
100baseTX full-duplex
100baseTX
10baseT/UTP full-duplex
10baseT/UTP
Physical true
Device igb0
mtu 1500
macaddr_hw **:**:**:**:**:**(censored)
Media 1000baseT <full-duplex>
Media (Raw) Ethernet autoselect (1000baseT <full-duplex>)
Status up
nd6
flags
performnud
ifdisabled
auto_linklocal
Routes default
192.168.1.0/24
Dynamic nameserver received 192.168.1.254
Dynamic router received 192.168.1.254
Identifier wan
Description WAN
Enabled true
Link Type dhcp
addr4 192.168.1.64/24
addr6
IPv4 Addresses
192.168.1.64/24
VLAN Tag
Gateways 192.168.1.254
Driver igb0
Index 1
Promiscuous Listeners 0
Send Queue Length 0
Send Queue Max Length 50
Send Queue Drops 0
Type Ethernet
Address Length 6
Header Length 18
Link State 2
vhid 0
Data Length 152
Metric 0
Line Rate 1.00 Gbit/s
Packets Received 933632
Input Errors 0
Packets Transmitted 2924366
Output Errors 0
Collisions 0
Bytes Received 92848184
Bytes Transmitted 3943197945
Multicasts Received 168
Multicasts Transmitted 0
Input Queue Drops 0
Packets for Unknown Protocol 0
Hardware Offload Capabilities 0x0
Uptime at Attach or Statistics Reset 1
My first suspicion was:
The ISP provided box (NH20A) doesn't provide a 10/100/1000/2.5/5/10 capable port. I wasn't able to find the exact specs online, BUT, and here's the real kicker:
I have an optional device provided by TELUS. They use it as a "wifi booster". It's a
Boost3.0
Hardware version: R02
Software version: 1.05.10 build06
This device has 3 RJ45 ports
one 10G
one 2.5G
one 1G.
When I plug things in this order:
ISP fiber to the home -> NH20A fiber port -> NH20A 10G RJ45 port -> cat6cable -> DEC750 igb0 port = I get 1000baseT auto-negociated
AND
when I plug:
ISP fiber to the home -> NH20A fiber port -> NH20A 10G RJ45 port -> cat6cable -> R02 (wifi booster device) 10G port = I get 10G speed to NH20A
R02 2.5G port -> cat6 cable -> DEC750 igb0 port = I get 1000baseT auto-negociated
BUT
when I plug:
ISP fiber to the home -> NH20A fiber port -> NH20A 10G RJ45 port -> cat6cable -> R02 (wifi booster device) 2.5G port = I get 2.5G speed to NH20A
R02 10G port -> cat6 cable -> DEC750 igb0 port = I get 1000baseT auto-negociated
so my conclusion is that the NH20A 10G port IS probably capable of 10/100/1000/2.5/5/10
Therefore, I am seeking your help to configured my DEC750 RJ45 2.5 capable ports to the correct speed in order to connect it to the NH20A box and get a 2.5G link.
Alternatively, I could maybe get 3x cat5e or cat6 cables from the 3x 1G ports between the DEC750 and the NH20A and aggregate them, but that seems janky, even for a noob like me!
(sorry for the wall of text, I wanted to be as clear and detailed as possible as I value your time)
Best regards,
Bhoriss
Multi-Gig-Modes (2.5 and 5Gbps) are not a mandatory part of an implementation of 10GBaseT. In other words, if one interface advertises the mode and the other doesnt know it, they cannot link in that mode, but only in the highest common mode.
There is no way of adding the mode if the interface doesnt know it (usually, in production).
Quote from: sternchen45 on June 24, 2026, 03:07:41 PMMulti-Gig-Modes (2.5 and 5Gbps) are not a mandatory part of an implementation of 10GBaseT. In other words, if one interface advertises the mode and the other doesnt know it, they cannot link in that mode, but only in the highest common mode.
There is no way of adding the mode if the interface doesnt know it (usually, in production).
Hi sternchen45, thank you for your reply.
Yes, that is in fact why I tested the 10G port on the NH20A with the 2.5G port on the R02 and they did, in fact, negotiate a 2.5G speed link between each other.
My issue is that when I plug the NH20A with my DEC750, they do NOT negotiate anything higher than 1G and I believe the problem is on the side of the DEC750.
Since the DEC750 advertises a port capable of 2.5G, maybe my problem is from opnsense, or maybe I missed a guide somewhere telling me how to manually set the speed of a port.
You can manually set the speed by assigning the parent interface (Interfaces -> Assignments -> assign igcX directly).
Go to "Interfaces -> igcX" and enable the interface. Save. Then change the speed with the "Speed and duplex" settings, e.g. to "2500Base-T".
This setting will not show up on any VLANs or Laggs, only on the actual hardware interface when it is assigned.
There are different generations of the DEC750 - I have one with 2x 10G and 3x 1G. Only the newer ones have 3x 2.5G.
And the 10G ports do not support anything but 1G and 10G.
Quote from: Monviech (Cedrik) on June 24, 2026, 04:51:27 PMYou can manually set the speed by assigning the parent interface (Interfaces -> Assignments -> assign igcX directly).
Go to "Interfaces -> igcX" and enable the interface. Save. Then change the speed with the "Speed and duplex" settings, e.g. to "2500Base-T".
This setting will not show up on any VLANs or Laggs, only on the actual hardware interface when it is assigned.
Thank you for your reply. Sadly, it seems 2500Base-T is not available to my interface options when I try to set it. Screenshot "2" shows the options presented to me.
Then you have the older 1G model just like me.
Quote from: Patrick M. Hausen on June 24, 2026, 04:51:55 PMThere are different generations of the DEC750 - I have one with 2x 10G and 3x 1G. Only the newer ones have 3x 2.5G.
And the 10G ports do not support anything but 1G and 10G.
Quote from: Patrick M. Hausen on June 24, 2026, 05:06:29 PMThen you have the older 1G model just like me.
Very interesting and disappointing. I was not aware the 2 versions existed under the same name. I can't find any details online about 2 versions and my box doesn't show any version number. Do you know how I can figure out which version I bought?
Well what are your interface names?
Just do an "ifconfig" in the shell.
If it shows "igb" its gigabit and "igc" are the multi gigabit ports.
Quote from: Monviech (Cedrik) on June 24, 2026, 05:11:16 PMWell what are your interface names?
Just do an "ifconfig" in the shell.
If it shows "igb" its gigabit and "igc" are the multi gigabit ports.
my interfaces are igb. then it is solved, I was sent the older version of the DEC750 with 1G RJ45 ports instead of the 2.5G ports.
Imma go cry in my corner now.
Thank you all for the help!
Did you buy directly from Deciso or was it from somewhere else?
Quote from: Monviech (Cedrik) on June 24, 2026, 05:15:39 PMDid you buy directly from Deciso or was it from somewhere else?
I bought from the opnsense store in 2023. 799 euros
Seems like I bought a couple of months before the V2 PDF was updloaded....
Ah okay that makes sense. Well nothing that can be done about this now.
No problem happy to help.
If anyone ends up on this post and is in a similar situation to me, aka
DEC750 V1 owner (3x 1G RJ45 ports) and ISP modem doesn't have any available SFP+ ports.
I ended up setting up a LAGG (interfaces>devices>LAGG) with 2 igb interfaces and the load balance protocole (LACP wasn't working with my particular modem).
Now, overview reports a 2G/s link to the modem. Here's to hoping things will be stable from here.
Thank you again to everyone that replied,
best,
Bhoriss
LAGG between router with the Layer2 hash algorith (Load balancing) eventually is only a failover method, not increasing link capacity
Consider other hash algorithms with other layers to better balance the load.
plugging in one of those 10G SFP+ Copper (10GbE) transceivers will probably work - if you have a free SPF+ (AX) port on the DEC. They can run quite hot, but you would get 10G between your modem and the OPNsense box.