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SDFadfasdfadsf
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Posts: 20
Joined: Sun Feb 07, 2016 2:21 am

vlan trunking

Sun Feb 07, 2016 5:44 am

It seems like 802.1q config is so conterintuitive on RouterOS.

Image

CRS125 as access switch
  • eth1 to client computers untagged (or an unmanaged switch), untagged on link, vlan 10
  • eth2 to hypervisor, 802.1q trunk carrying vlan 10, 11, 12
  • eth24 to gateway RB750G, 802.1q trunk carrying vlan 10, 11, 12
RB750G as gateway
  • eth1 to Internet, snat masquerade configured
  • eth2 to CRS125_eth24, 802.1q trunk carrying vlan 10, 11, 12
  • eth3, untagged on link, vlan 10
  • eth4, untagged on link, vlan 9
From what I understand, CRS vlan config is quite different from old platform like RB750G. In either case, switching and routing are logically separated and each has a vlan database. I am so confused.
 
SDFadfasdfadsf
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Posts: 20
Joined: Sun Feb 07, 2016 2:21 am

Re: vlan trunking

Tue Feb 16, 2016 12:22 am

I just can't figure out how switch VLAN works on RG750G. And it gets difficult to troubleshoot because NICs strip the 802.1q tags if there is any.
 
lambert
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Posts: 533
Joined: Fri Jul 23, 2010 1:09 am

Re: vlan trunking

Tue Feb 16, 2016 1:30 am

The MikroTik switch configuration methodology in RouterOS is second in frustration quotient only to an HP switch I dealt with 10 years ago. MikroTik could at least make a wizard in WinBox which could allow you to select tagged and untagged radio buttons per defined VLAN and generate the arcane code on the backend automagically.

I've not tried VLANs on an RB750, so I'm not sure which switch chip it has.

I think some of the lesser switch chips, i.e. the ones *not* used in the CRS devices, may not have the ability to switch tagged to untagged ports themselves. I tried really hard with a CCR1009's four port switch and failed last weekend. I finally just created VLAN interfaces and bridged them to the ports I wanted untagged. The CCR had the horsepower so I wasn't too worried about it. I also failed to accomplish what looked like it should be possible with the switch chip on an RB493G about a year ago. But I didn't dig in too hard on that one.

In your case, I would probably create ether2vlan10, ether2vlan11, and ether2vlan12 on the RB750. I would then create bridges named VLAN10 and any other VLANs which need to be on multiple interfaces. I would add ether2vlan10 as a port in the VLAN10 bridge. I would add ether3 as a port in the VLAN10 bridge. According to the layout specified in your original post, that would have you all set. I suspect your specification is incomplete or has at least one typographical or logical issue since "vlan9" is specified only on ether4 of the RB750 and is untagged there. In a router, it's not really a port based VLAN. It's just another, probably routed, interface.

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