Hi.

 

Just to preface, I'm not new to vlans but this bug has me stumped.

 

I'm using the SG108PE in a test setup and seeing some very strange behaviour.

I have both a V2 and v3 on latest firmware and both are exhibiting the same behaviour.

I'm running an x86 machine running pfsense as router

Default vlan 192.168.0.254/24 dhcp

Vlan 10 192.168.1.254/24 dhcp

vlan 1337. 10.0.0.254/24 static only

Setup trunk to a mikrotik 48 port switch 10.0.0.253

From there I have also have 2 trunks to each of the tplinks mentioned. 10.0.0.240 and 10.0.0.241

 

The tplinks are setup as follows.

802.1q vlan enabled

 

Ports 1-7 untagged vlan 1

Port 8 tagged vlan 1

Ports 1-8 tagged vlan 10

Port 8  tagged vlan 1337

 

The theory here is that access devices, port 1-7, untagged get a 192.168.0.x address.

Tagged vlan 10 devices port 1-7 will get a 192.168.1.x address.

 

Everything is working great except for some reason every 5-20 minutes I lose access to the webui of both tplinks for about 5 minutes. Then it comes back for another 5-20 mins, then off again repeating constantly.

I also cannot ping the tplink during this time whilst the webui is unavailable.

The weird thing is that the devices that are plugged into the tplinks continue to work normally.

E.g. VoIP phone on vlan10 plugged into port 1 of the tplink is still working as expected and accessible from a pc on vlan1 plugged into the mikrotik switch.

Only web access and pings directly to the tplinks fails

 

I also changed the vlan on port 7 to be a trunk and placed another mikrotik switch on port 7 10.0.0.252.

Whilst I'm unable to access the tplink I can access the mikrotik on vlan 1337 port 7 from a pc on vlan 1 plugged into the other mikrotik switch on port 8 of the tplink.

This again confirms that the network is still routing correctly and the tplink is passing traffic correctly.

Just for whatever reason it's webui and pings are failing intermittently for minutes at a time.

 

I know these are pretty simple devices but did anyone have any suggestions as to how I can try to diagnose this further.

The issue is only effecting the tplinks and not any of the other devices on the same vlan, either in front or behind the tplinks.