VLAN usage under Proxmox
Hello,
Just spent a good week installing my home server. Time to pause and lookback to what I've setup and ask your help/suggestions as I am wondering if my below configuration is a good approach or just a useless convoluted approach.
I have a Proxmox instance with 3 VLAN:
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Management (192.168.1.x) : the one used by proxmox host and that can access all other VLANs
-
Servarr (192.168.100.x) : every arr related software + Jellyfin (all LXC). All outbound connectivity goes via VPN. Cant access any VLAN
-
myCloud (192.168.200.X): WIP, but basically planning to have things like Nextcloud, Immich, Paperless etc...
The original idea was to allow external access via Cloudlfare tunnel but finally decided to switch back to Tailscale for "myCloud" access (as I am expected to share this with less than 5 accounts). So:
- myCloud now has Tailscale running on it.
- myCloud can now access Servarr VLAN
Consequently to my choice of using tailscale, I had now to use a DNS server to resolve mydomain.com:
- Servarr now has pihole as DNS server reachable across all VLAN
On the top of all that I have yet another VLAN for my raspberry Pi running Vaultwarden reachable only via my personal tailscale account.
I'm open to restart things from scratch (it's fun), so let me know.
Also wondering if using LXCs is better than docker especially when it comes to updates and longer term maintenance.
I don't think there is anything wildly wrong with it, but it seems like you're doing all of this at the router, unless you have dedicated switches for each VLAN?
VLAN is not a security feature, it's a logical separation of IP segments. Maybe I'm missing your intention here, but just setting different IP spaces on VLANs and then bridging them doesn't help your security, it just complicates your network.
Not OP, but logical separation and firewall rules is a needed first step for security. They already mentioned in the post that one vlan has dedicated outbound (via VPN only) and doesn't have access to their .200.
Physical switches per vlan is completely unnecessary, and entirely why vlans are used rather than subnets.
Yes the idea is to make it easier to isolate/configure firewall rules and try to protect more sensitive data. (i.e. I don't care much if people can access my ISOs ;) However, at the end of the day they are all on the same Proxmox host.
You can't use the same subnet on different vlans if you ever intend for both of them to reach the internet. In that case you'd need a second router which just defeats the purpose
You dont need to have the same subnet on different vlans. You also dont need them to each have a router, that isn't how this works.
Each VLAN gets a gateway, in a subnet accessible within that VLAN.
Under no circumstances do you need a separate physical router for having 2 VLANs on the same network. That's not how VLANs work.
The poster i was responding to equated subnetting to vlans. I might have misunderstood what they meant though. It sounded like they wanted to use the same subnet per vlan, which wont work if you want them routed in the same gateway.
Reading it again they make it sound like you can't subnet all of these networks on a switch without vlan, which you definitely can. I could for example connect 4 different devices on the subnet 192 168.10.x/24 and have them reach each other. I could also connect 4 more devices in the same switch but on a different network 192.168.20.x/24 and it would work.
You were responding to me, and I most definitely didn't equate the two. Maybe you meant to respond to someone else.
In any case, you can route between vlans (and subnets), but without a route you aren't communicating between those vlans or.between subnets.
Also, you can have multiple subnets in a vlan, but you can't have a single subnet across vlans.
The range (x.x.10.x and x.x.20.x from your example) is only the subnet side, you could have both of those subnets in one vlan. But you could not, for example, have x.x.10.x/24 exist in vlan 10 and vlan 20.
Sorry about my confused rambling 😅 Yes, the example was to demonstrate the difference between subnetting and vlan. Albeit simplified. What you said is right.
They are all defined as 192.168.x.y/24 Doesn't this make them in different subnets?
Yes.
And to be clear about things, because that comment doesn't make any sense for VLANs - a VLAN can contain multiple subnets. You will not have a single subnet across multiple VLANs.
Your config is fine in that regard.
Not saying physical switches are needed for security, which is why I was asking for clarification. Doing all of this on a router doesn't make sense without a physical separation though. That's my point. If the router gets owned, they have access to all networks anyway. If the idea is just for traffic direction and shaping, then I'm confused why the bridged pihole.
I'm going to have to say, I have zero idea why you would suggest this for something that is logical, and specifically not physical.
Logical separations and vlan segregation for trust models is standard practice (though hopefully more will trend towards a zero trust model, but irrelevant here). There is zero need for any physical separation. What are you talking about?
Friend...you clearly are not reading what I'm saying. Not one single sentence that I've typed suggested there needs to be, or ever was a physical separation. That is why this setup without clarification doesn't make much sense if security is the goal.
You are saying exactly what I'm saying and arguing about it for some reason.
Your first sentence was about physical switches...
There already is a logical separation that makes perfect sense - out through VPN with no network access initiated by that VLAN to the other two internal. That'd a security step that's pretty clear and valid off the bat.
So again - I don't follow anything of what you're driving at, no. Because from the first sentence in your first comment forward isn't making any sense.
Please, clarify, because I don't know why you'd even bring up different switches for an extremely basic logical separation.
VLAN on a singular router without physical separation is not secure. OP was asking for feedback, that's my feedback. It's accurate.
Thx for the feedback, I don't have multiple router no. If I had would it be still called VLAN? I thought the V was Virtual for achieving that LAN segmentation with one router. With one router, don't you think the security added is the same level as configuring a firewall on each VM/LXC ?
Your understanding is correct.
Multiple routers is irrelevant and ridiculous.
Well it wouldn't matter if your router is the thing that someone gets into. All you're doing is separate traffic in different subnets, and if that's your goal, you're good to go.
You are aware that a firewall rule is how you would address - in software, with logic - someone trying to get from VLAN C to VLAN A, right?
That its part of the method you'd use as a layer of security to prevent someone gaining access to.your router?
Assuming the router is compromised from the start is similarly just nutso.
You are aware that being on the router would have access to ALL the ingress and egress interfaces, right?
That's not how any of this works.... At all.
No, its managed by the firewall. The existence of a VLAN does not grant it access to egress. The firewall needs to permit that behavior.
Your entire understanding of how a logical network works is wrong. I'm not trying to be a dick - this is just really bad information that you're sharing.
JFC 🤦
How are you NOT understanding what OP thinks is happening, versus what you thinks is happening?
If I get shell access to this router I have access to ALL NETWORKS. VLAN won't help any of this.
That's... Insane feedback.
But sure.
Please inform me of how that's..."insane"?
Because the overwhelming majority of multiple vlan use, and proper use at that, is going to be managed by a single firewall at the end. Because that firewall is going to manage intra and inter vlan communication, and to suggest that requires a different physical router is... Wild.
Because logical network design - regardless of egress - is a vital component of any security implementation.
Because having a multiple egress solution that doesn't rely on a software based connection (VPN) would be absolutely bonkers for a self hosted solution at home.
There are just... So many things that are absolutely buck wild crazy to me in what you've said. And not in a fun 'yee haw' kind of way, but a "boy oh boy if that could be bottled it would sell like hotcakes on the street" sort of way.