Hello selfhosted.
My router just burnt up and instead of buying a new one, I’m thinking of turning my own built NAS/home server into a router. Is this possible?
The server in question is a normal computer running debian, where I have a few disks in RAID and host some web services. The motherboard only has one RJ45 port, so my guess is that I have to at least get a network card that supports 2 ports. I’m no stranger to linux but physical networking is not my home field, though I’m very interested.
If someone could point me in the right direction, I would be more than happy.
OPNSense is a great option for turning x86 hardware into a router. That said, I would not recommend combining your router with other functionality. The router should be a dedicated system that only does one thing. Leave your NAS and web services on another machine.
Hey there! Sorry, I got busy with work today.
I was just noticing that you have plenty of replies. I think you seem to have enough to go on with.
If you still need anything, hit a reply to this one and I can give you my 2-cents worth of opinion.
Not sure if others already said this (I seem to see mostly comments explaining how to do it, but didn’t read them all), but, while it’s certainly feasible, you may not want to do that.
A router is the cornerstone of your network (if it goes down, so does the network) and if you are a self-hoster you’ll probably fiddle endlessly with your home server, and of course break it from time to time… the two things just don’t go well together.
Personally, I’d recommend getting some second-hand router appliance that can run openwrt and use that (make sure to check the flashing procedure before deciding what to buy - some are easier than others). Or you could get a dedicated x86 machine… probably overkill though.
I truly understand this sentiment, and if I ever find it troublesome to maintain, I will do just that, but right now I just want to use this as an excuse to fiddle around haha ;). I don’t run anything high-profile and my server uptime is still on par with the frequent power outages in my area
I’ve gone down this path.
You want an archer c7 with OpenWRT. I got one for 5 dollars on marketplace, flashing it took all of 2 minutes, and it kicks ass.
You can use OPNSense inside a virtual machine. You can use QEMU or install the Proxmox toolkit over Debian to manage it. I’ve been using this setup for years without issue.
You’ll have to create a bridge network for the WAN and the LAN interface, connect them to the VM, then configure the virtual interfaces inside OPNSense.
Only issue I’ve had with this setup is if you’re running in a cluster and you have to restart the cluster then you run into a deadlock. The cluster won’t start VMs without a quorum and it can’t form a quorum without the OPNSense VM up. So you have to manually intervene.
Ah I see, did not think of that. A network card with two ports would be enough right? One for the modem, and the other for clients, which ideally could be a switch, for more ports. That’s possible right?
Yes, that will be enough. You can also use a single port on the NIC and the one on the motherboard if it can handle the ethernet speed you want.
This is my network setup on Proxmox:
vmbr0is a bridge that has a single port going to the modem. The OPNSense VM’s first virtual interface is connected to this and configured as a WAN interface. Nothing else connects to this bridge as it is exposed to the internet.vmbr1also has a single port that goes to the physical switch. OPNSense’s second interface connects to it as a LAN port, as well as every other VM and container running on the server.I see, very nice. That would reduce the cost quite a bit. Thank you
Yes, that’s possible
This is extremely possible and I have done a lot of stuff like it (I set up my first home built Linux firewall over 20 years ago). You do want to get some kind of multiport network card (or multiple network cards… usb -> ethernet adapters can do OK filling in in a pinch). It also gives you a lot of power if you want to do specific stuff with specific connections (sub netting, isolation of specific hosts, etc).
There’s a lot of ways to do it, but the one I’m most familiar with is just to use IP tables.
The very first thing you want to do is open up /proc/sys/net/ipv4/ip_forward and change the 0 to a 1 to turn on network forwarding.
You want to install bridge-utils and isc-dhcp-server (or some other DHCP server). Google or get help from an LLM to configure them, because they’re powerful and there’s a lot of configs. Ditto if you want it to handle DNS. But basically what you’re going to do (why you need bridge-utils) is you’re going to set up a virtual bridge interface and then add all the various NICs you want on your LAN side into it (or you can make multiple bridges or whatever… lots of possibilities).
Your basic iptables rule is going to be something like
iptables -t nat -A POSTROUTING -o enp1s0 -j MASQUERADE, but again there’s lots of possible IP tables rules so read up on those.
I had a very similar problem as @Toralv@lemmy.world a few weeks ago. I repurposed a small, fanless x86 desktop computer as my new router. It has only one RJ45 port and due to its small size cannot be extended with a proper network card. As it has an unused USB3 port, I acquired a cheap Realtek-based USB3-to-RJ45 ‘adapter’ as the second network interface. It works without any further issues in Linux (Arch) and has no problems to handle Gbps traffic.
For the router configuration, I am using ‘nftables’ instead of ‘iptables’, as the former is supposed the successor of the latter. I only used the new nftables configuration, but there are wrappers available so that one can continue to use iptables syntax if desired.
For network configuration, I am using systemd’s networkd. Check systemd.network(5): Configuration option ‘IPMasquerade’ takes care of telling nftables/iptables to setup masquerading (rendering the iptables invocation @thebardingreen@lemmy.starlightkel.xyz exemplified unnecessary), options ‘IPv4Forwarding’ and ‘IPv6Forwarding’ renders manually changing ‘/proc/sys/net/ipv4/ip_forward’ unnecessary.
systemd’s networkd has a built-in DHCP server; check option ‘DHCPServer’ and section ‘DHCPServer’ for that (same man page as above). This way you can skip installing/configuring a separate DHCP server, but systemd’s DHCP server has some limitations, such as only supporting DHCPv4 and lack of proper command line tools. For example, to retrieve the list of current leases, you would have to make a dbus call to networkd, e.g. via busctl or dbus-send.
Bridges can also be configured with systemd’s networkd, making a separate bridge tool unnecessary. Rather straight-forward with three small configuration files, telling networkd that you want to have a bridge, its name (e.g. br0), its MAC address, which NICs will be part of the bridge, and the bridge’s configuration like a NIC itself (e.g. static IP address, that the networkd’s DHCP server shall listen here, …).
systemd’s networkd has a built-in DHCP server; check option ‘DHCPServer’ and section ‘DHCPServer’ for that (same man page as above).
Is that true in Debian? If so, cool. I did not know that.
This was my first thought. I have some experience with iptables so I think this would be doable. Thank you
I’d recommend
dnsmasqfor a DNS/DHCP server component. It is time tested, used on some consumer routers as a daily-driver industry component. It has a far easier learning curve compared to the like of ISC’s offering, and the feature gaps are not going to affect you until you have a firm grasp on many deeper DNS or DHCP nuances.I’m happy to answer specific questions as you dig into it. :) Good luck.
As others have mentioned this is practical with a VM. It might also be doable with Docker, saving some resources.
I know you can run openwrt as a VM on a NAS. Might be a good solution for you. Theoreticaly you can use virtual interfaces and bridges on the NAS to use a single fysical network interface. But a second card will be the most easy option
First question. Was your router also your modem? As in describe each connection/device from street until you get to your router. (Do you also know your connection type? Some flavour of DSL, HFC, Fiber?)
No, the modem is separate (fiber).
👉
There! Happy?
Here’s a pretty good tutorial on how to do this on a system with two network cards https://medium.com/@lfoster49203/setting-up-ubuntu-as-a-router-with-advanced-routing-features-4511abc5e1eb
Thank you
First thing I’d troubleshoot… Is your router the issue, or the modem that decodes the signal from your ISP?
Last I checked, router/AP stuff is pretty easy to DIY (OpenWRT, PFsense, etc). But that’s the step after the modem has done what it needs to do.
My router physically burnt up, up in flames. No idea why, tired of life I guess.
The 8K porn was too hot.
Short answer: yes
Though anything else I could not say better than this guide: https://opnsense.org/get-started/
Sorry I was probably not very clear on one part, I’m looking to run a router additionally to my already existing debian installation. OPNsense seems very nice, but that would require me switching to FreeBSD, which I’m not very keen on right now.
Well all Linux systems can easily be turned into routers if they have 2 or more networking ports.
All you have to do is enable routing, the firewall rules for routing internal traffic and restrictions on external traffic, and dhcp services to the internal network (assuming that you don’t have a dedicated dhcp server)
Here is an example: https://github.com/dhenkes/router
Basically any Linux router guide (for any Linux distribution) can be used with minimal translation as they are all going to be using the exact same software with virtually identical configurations.
