Grandstream IPv6 weirdness with VLAN

Forums › LAN (ethernet/Wifi/routers/Bluetooth) › Grandstream IPv6 weirdness with VLAN

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itsme4you

3 posts

Wannabe Geek

#3408913 31-Aug-2025 05:56

Hi I had similar issue and today updated to beta version firmware but still having slow connection for 1gig connection getting hardly 100mbps.

From switch getting 2 vlans connected to 2.5gb port.

And configured2 ssid for each vlan , both are not exceeding 100mbps. Not sure what the issue but for the same setup with openwrt on belkin rt3200 getting nearly 850mbps speed.

Can you share what configuration you did on ssid. Can you share pls.

Thanks

Krish

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#3408915 31-Aug-2025 07:45

Are you using the same cables with both Belkin and Grandstream?

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itsme4you

3 posts

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#3408924 31-Aug-2025 09:41

Yes same cable.

nzkc

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#3408996 31-Aug-2025 13:35

itsme4you:

Can you share what configuration you did on ssid. Can you share pls.

No VLAN on my main SSID

And VLAN 20 on my IOT SSID

Client IP Assignment set to bridge on both

Thats it. Nothing clever at all.

itsme4you

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Wannabe Geek

#3409032 31-Aug-2025 17:45

nzkc:

itsme4you:

Can you share what configuration you did on ssid. Can you share pls.

No VLAN on my main SSID

And VLAN 20 on my IOT SSID

Client IP Assignment set to bridge on both

Thats it. Nothing clever at all.

Are you using 2 wires to connect to wifi router?

One with out vlan and 2nd with vlan?

nzkc

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#3409044 31-Aug-2025 19:24

itsme4you

Are you using 2 wires to connect to wifi router?

One with out vlan and 2nd with vlan?

No. Single ethernet cable to the AP.

And settings are unchanged (as far as I can remember):

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RunningMan

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#3418723 25-Sep-2025 13:23

https://firmware.grandstream.com/Release_Note_GWNAP_1.0.25.41.pdf

1.0.25.41 has been released with fixes for IPv6 & VLAN issues.

Fixed issue where IPv6 traffic was not occasionally tagged.
Fixed device performance degradation when VLANs are enabled.
Fixed client disconnection issue due to 802.1X un-authentication failure.
Fixed tagged traffic handling issue in access mode when DSCP is non-zero.
Fixed long reconnection time issue after client reconnects to office Wi-Fi AP.
Internal bug fixes

nzkc

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#3473699 25-Mar-2026 18:03

So I have come to the conclusion this is still actually an issue. And I've been able to identify that RA packets leak across VLANs (I have a few now) with IPv6. Ive still got a ticket open (since July 2025) and have provided a stack of information to Grandstream. Unfortunately they seem to be dragging their heels a bit on it.

Best mitigation I have right now is to disable IPv6 on my VLANs. Thats frustrating, but manageable. Even then I still see RA into those VLANS (when connected over WiFi) from the non tagged LAN where I'm still running IPv6. This was causing no end of problems - mostly performance). Most of the IOT devices I have only get IPv4 addresses so not really noticeable there. However; I got some cameras and wanted them in their own VLAN and thats where my struggles grew and I eventually stumbled onto the packets leaking.

I would love to know if this is only on GWN7665 devices or is further but dont have other devices to confirm with. Anyone able to test and confirm?

I found this was a problem with both dedicated VLAN SSIDs and when using PPSK to set a VLAN for particular devices.

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