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porch
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Plugging laptop into VLAN port, blocks bridge interface of other router.

Tue Mar 21, 2023 4:06 am

I have a strange one. This is with two 2011UiAS-2HnD.
LivingRoom 192.168.1.24 (spf1) -> (spf1) BatteryRoom 192.168.1.25

The BatteryRoom router is doing most of the work. Duel WAN, VLANS, VPNs, etc. The LivingRoom router is working as a WIFI access point, and some of the ports are assigned VLANs, but that is it.

When I plug a laptop into port 5 of LivingRoom, it is on VLAN3, gets a DHCP address from the VLAN3 (192.168.3.0/24) pool (on BatteryRoom router), and everything just works fine.
When I plug the same laptop into port 2 of LivingRoom, it is on VLAN4, gets a DHCP address from the VLAN4 (192.168.4.0/24) pool (on BatteryRoom router), and it can access the internet, but within seconds, nothing else can ping BatteryRoom at 192.168.1.25. Everything else goes down. I can ping things in the 192.168.1.0/24 subnet, even stuff connected to the BatteryRoom router, but I can't ping the router itself. BatteryRoom router itself at 192.168.1.24 can't ping BatteryRoom at 192.168.1.25.
Unplugging the laptop from port 2, and after 3 minutes or so, I can ping 192.168.1.25 again and everything returns to normal.

I don't see a difference between VLAN3 and 4. It's like an MAC address collision, but I checked the ARP table and the MAC address on the laptop, and it is not the same as anything on the 2 routers.

Anyone see something like this before?
Sanitized configs attached.
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anav
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Re: Plugging laptop into VLAN port, blocks bridge interface of other router.

Tue Mar 21, 2023 2:03 pm

When you decide to have one bridge, and all subnets on vlans, I can help.
 
porch
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Re: Plugging laptop into VLAN port, blocks bridge interface of other router.

Wed Mar 22, 2023 2:06 am

That is the end goal.
At the moment, I need to replace a switch with a managed one for the 192.168.2.0/24 subnet and make that subnet a real VLAN, and also workout how I can assign a wifi interface to that VLAN2. But first, I am trying to make VLANs work as expected.
Little steps.
 
tdw
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Re: Plugging laptop into VLAN port, blocks bridge interface of other router.

Wed Mar 22, 2023 3:04 am

Have you at some point imported a .backup from one of the Mikrotiks to the other? The mac-address=E4:8D:8C:7D:AF:xx settings under /interface ethernet suggest this, in which case you may have duplicate MACs which confuse the bridge/switch forwarding tables.

There are also potential issues on devices using ports on multiple switch chips which are members of the same bridge, see https://help.mikrotik.com/docs/display/ ... witchchips
 
porch
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Re: Plugging laptop into VLAN port, blocks bridge interface of other router.

Wed Mar 22, 2023 3:43 am

Have you at some point imported a .backup from one of the Mikrotiks to the other? The mac-address=E4:8D:8C:7D:AF:xx settings under /interface ethernet suggest this, in which case you may have duplicate MACs which confuse the bridge/switch forwarding tables.

There are also potential issues on devices using ports on multiple switch chips which are members of the same bridge, see https://help.mikrotik.com/docs/display/ ... witchchips
I don't ever recall importing a backup from one to the other. But at some point,I did notice the the bridges had the same mac address and I had to change one.
At the moment, I am keeping the VLANS on switch 1, but I will look into that when I expand.
Thanks
 
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Re: Plugging laptop into VLAN port, blocks bridge interface of other router.

Wed Mar 22, 2023 4:21 am

The addresses would initially be different so they must have been transferred across at some point. Use /interface ethernet [find] reset-mac-address to restore the inbuilt MAC addresses on the ethernet interfaces, other references (bridge admin, secondary wifi, L2 tunnel interfaces) have to be adjusted manually.
 
porch
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Re: Plugging laptop into VLAN port, blocks bridge interface of other router.

Wed Mar 22, 2023 11:11 pm

The addresses would initially be different so they must have been transferred across at some point. Use /interface ethernet [find] reset-mac-address to restore the inbuilt MAC addresses on the ethernet interfaces, other references (bridge admin, secondary wifi, L2 tunnel interfaces) have to be adjusted manually.
Thank you. I reset all the Ethernet macs, removed the bridge admin mac, and gave the secondary wifi a different mac, and my problem went away.
That was a strange one I didn't think about.
Thanks for the help.

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