VLAN and port tagging confusion

ebuckland81 · January 23, 2025, 7:04pm

I’m in the midst of fiddling with VLAN and port tagging and I’m very confused. I get strange outcome on VLAN listed per device.

VLAN 90, 192.168.90.1/24, setup as Isolated, and firewall rule allowing traffic from 192.168.90.0/24 LAN to WAN (may not be necessary?). The purpose is to keep my old router underneath the Route10 for the time I’m migrating devices, while still allowing access to internet, and for learning how to set up VLANs as well.

Furthermore:
Short lease time, 60 s, setup for VLAN 1 and 90 for testing.
Device (Asus router) → VLAN 90, IP Static 192.168.90.2 (and left blank in a second try)
Route10, WAN#1 (first port from the left) → Mode Standard, Color Black, Native VLAN 90, Allowed VLANs 90 only.

Port shows as U for VLAN 90 in Route10 ports layout.

I get access to Internet through my old router, IP shows as intended (also with dynamic IP in the correct VLAN subnet) but in the devices list I get VLAN printed as 2. Anyone with comments on that? Seems like a bug in the printout or does it reside in a VLAN 2 that is not even defined?!

Also, if I set Devices VLAN to blank (remove 90) the connection to the Router is lost. It seems like blank is interpreted as Default VLAN 1 (?), as the corresponding Route10 Native VLAN is reverted to Default at the same time.

Then, if I change the Route10 port Native VLAN to 90 again I regain access. But, I would have thought that any device attached to the Untagged port assigned for VLAN 90 traffic would show up automatically on VLAN 90 with IP in the corresponding subnet. Is this also a potential bug or have I misunderstood it all?

When I try the same maneuver for a VLAN 30, also short lease time but not Isolated, for two streaming devices attached to an unmanaged switch connected to Route10 I end up with them on the correct subnet for dynamic IP, corresponding to VLAN 30, but they show up as VLAN 1 in the devices list. Hmmm?

All WiFi devices shows up with correct VLAN corresponding to VLAN setup per WiFi SSID.

Alta-Matt_v2 · January 23, 2025, 7:11pm

Can you explain the intent of the Asus router in this equation? It sounds like you’re trying to route a VLAN through the Route10 but another VLAN through the Asus router?

ebuckland81 · January 23, 2025, 7:27pm

The intent is just to have an isolated passage from my Asus router through to the ISP. It is not overly necessary but I got very confused over why the router showed up as VLAN 2 in the context of Route10 devices. The Asus router is free of VLAN except for any native VLAN.

Alta-Matt_v2 · January 23, 2025, 7:28pm

So the topology would be

Route10 → Asus Router → Various clients?

ebuckland81 · January 23, 2025, 7:32pm

Yes, indeed. A few clients already moved and some not yet migrated from the Asus router to the Route10, and I want the non-migrated devices to still be up an running with internet access. So, as I mentioned, the internet access works but I’m confused over the VLAN listing.

Alta-Matt_v2 · January 23, 2025, 7:45pm

Ok, there’s really no need for a VLAN at all as the Asus router would take on a DHCP lease from the Route10, then through NAT and its own DHCP server, hand out addresses behind the Asus NAT.

However, it should be pretty straightforward if you wanted to add a VLAN.

Add VLAN
Specify VLAN number and the Router IP. Router IP will be the address assigned to the Route10 VLAN. In this case, I specify a /30 which allows for 2 addresses, 1 for the Route10 and one for the Asus which would be handled by DHCP
Click the interface the Asus will plug into
Specify the Native VLAN as the same VLAN number you specified in step 2
Check only that VLAN number

ebuckland81 · January 23, 2025, 8:06pm

Agree totally.

However, the intention was to follow exactly that procedure already before, so I would assume it should have worked. But to be sure I set up a new VLAN 91 right now as per your instructions (also with only one IP in the pool with your suggestion on /30). I assumed step 5. relates to the Allowed VLANs, and to check the specific VLAN, now 91, only. This time VLAN in the device list shows up as 26.

Edit: VLAN 26 is not among the defined VLANs.

Edit 2:
After a reboot I can perhaps see some sort of logic:
Devices on VLAN 30 gets VLAN 1 in list.
Devices on VLAN 40 gets VLAN 2 in list.
Device on VLAN 91 gets VLAN 3 in list.
Devices on VLAN 40 moved to VLAN 50 (port tagging changed) gets VLAN 12 in list, which is my 9 VLANs currently defined in Settings + the three used by the wired ports for VLAN 30, 40 and 91 above.
Devices on VLAN 50 moved back to VLAN 40 (port tagging changed back) gets VLAN 2 back in the list.

To me this looks like an index/iterator being printed instead of the actual VLAN ID. Is there perhaps some sort of array holding information on VLANs where the iterator gets printed instead of the VLAN ID?

Alta-Matt_v2 · January 23, 2025, 9:11pm

Yes, definitely appears to be a bug. Have you only attempted this on the Android app?

ebuckland81 · January 23, 2025, 9:20pm

The Alta Android app doesn’t show this kind of information from what I have been able to see. In the Alta Op app (!?), that I got suggestion to install when on the web controller page through Chrome on Android phone, shows this information. Not sure in what context/browser/app the controller is managed then, Chrome perhaps. Not tried on a computer browser yet.

Alta-Matt_v2 · January 23, 2025, 9:43pm

So the screenshots are from the web interface, just happens to be on an Android phone?

There’s no individual controllers. The web and mobile apps all talk to our cloud, so no worries about that.

ebuckland81 · January 23, 2025, 9:47pm

Yes, screenshots from an Android phone using the web interface.

Alta-Matt_v2 · January 23, 2025, 9:59pm

Can you invite me to the site, please?

ebuckland81 · January 24, 2025, 8:19am

Yes, done!

And, I was wondering if I should branch the following off to another topic to keep things organized:

Somewhat hidden in this topic was also the fact that updating a device connected to an Untagged port, associated to a specific VLAN, gets unintentionally (at least in my opinion) Tagged to that VLAN and Native VLAN set to Default.

E.g. if I set Native VLAN 90 and Allowed VLANs 90 for a specific port, it gets set to Native VLAN Default by saving the Device with a changed static IP (or changing from dynamic to static IP) even though the Device VLAN was blank before. Reverting from a static IP to dynamic IP (delete setting and leave field blank) does not overwrite the Native VLAN for the port.