My mobo has 2 built in NICs, one of which is 2.5G.
I have a NAS I built from old parts. Today I got a cheap 2.5G nic for it, since it seemed a dead simple upgrade to speed up transfers between my PC and NAS.
Making the connection breaks my network. This is not unexpected, but I’d like help in configuring things to work.
My NAS is on linux, my computer is on Windows 10.
It would also be cool to explain what we’re doing, instead of just giving me commands, so I can learn a bit of networking in the process.
For example, I know loops are bad, but am I creating a loop in this instance?
What does your IP assignment look like on the adapters that are directly connected?
I have done something similar with a unmanaged switch where the computers all 192.168.100.X and no gateway IP, while my main PC has an additional adapter that is 192.168.0.X with gateway to the router.
Can you also explain how the network is breaking? Is your internet access gone or the NAS Drive
First I let it auto, the I set unused IPs to the same subnet as my router. That’s a mistake.
On third try, I chose a different subnet.
My router network is
192.168.0.1 / 255.255.255.0
Computer: 192.168.0.2
NAS: 192.168.0.5
I tried putting the 2.5G nics on
Computer: 192.168.0.3 / 255.255.255.0
NAS: 192.168.0.4 / 255.255.255.0
That broke my LAN. I had internet, but my shares no longer worked.
I tried setting 192.168.0.3(4) / 255.255.255.255
Still no worky.
What worked is choosing a different subnet - e.g. 192.168.10.2 / 255.255.255.0
(Which does make sense, when I think about it. The default gateway for 192.168.0.x / 255.255.255.0 is 192.168.0.1.
So 192.168.0.3(4) would be unreachable from there.
Now I’m curious if there is a way to make it work on the router subnet?
Like an explicit route on both sides? But I’m not sure what it would be.
On windows it’s: route add destination_network MASK subnet_mask gateway_ip metric_cost
My other problem is, I’m only getting 1G speeds, even tho the Link speed is advertised as 2.5G (on both sides).
Trouble is, even if I map the drive using the 2.5G IP, I see no activity when using it!
Traffic is being set exclusively thru the 1G connection.
I also can’t get iperf to work thru that IP…
It’s not very clear what your NIC situation is, let’s clarify that first.
You mention using /32 and /24 subnets, and if I understood correctly trying to use 2 IPs in /32 (255.255.255.255) subnet which is not possible.
I’d start with configuring 2.5G NICs to a different subnet, so not the one on your router, than pulling 1G cables and testing the speed. This way your only possible link is 2.5G and you can begin to isolate the problem.
Maybe I didn’t present it in the best way, but I did give all relevant information above already.
Right now I am playing around with the routes.
What exactly am I isolating here? Once again, I have already confirmed traffic NOT going thru the 2.5G nic. It’s super easy to confirm because I can just open the connection status on windows, look at the packets sent/received and see them NOT moving when I copy a file.
Ah I was under the impression that the NAS was isolated and had a single 2.5G link to the PC. I now see it also has a 1G connection to the router (is this correct?)
We want to know if 2.5G works when there is no other NICs active. It is very unlikley for 2.5G NICs but if there is no Auto-MDI/X it may not work without a crossover cable. Just eliminating variables so we are sure direct connection works.
Well, I didn’t wanna shove myself back there, but okay. It is now confirmed. Tho I’m sorta dissapointed, I’m only getting around 160 MB/s transfer. Trying to make iperf work now.
Also, it needs to work WITH the other cable plugged as well.
I have a server set up exactly how you’re describing, and I ran into same problem with traffic going over the wrong interface.
In my case, using Windows 10, I had to unmap the drive using the old ip and reboot before remapping the new one. Without the reboot, traffic would go over the wrong interface.
Unfortunately that didn’t work for me. Traffic is once again flowing thru the 1G connection.
I think I will need to play around with the routing on both machines to fix this. But I’m starting from scratch over here. If anyone has other ideas, please share.
Yes, it’s empty. There is not gateway, to speak of. I understand at least that much of networking. Well… since today. Gateways route traffic outside of your subnet. There is no outside in this case.
I had this same kind of issue after setting up an old proxmox node with 10gbe on the network. When it was connected at all, it would nuke the internet for everyone. Not sure the setup or resolution exactly unfortunately but it would be nice to know what was going on in case I experience this again. Hope you get a good resolution so I can remember lol. Ill let you know if I remember anything that could potentially help.
It has been a while since I set mine up and my topology is quite different since I use a dumb switch for my devices (PiKVM, Scopes, Lab Instruments, NAS)