VLAN intercommunication

Hello there! I am new to routerboard, but learning quickly. I’ve got a RB750, generally configured the way I want. In general it’s working but there’s an oddity I’d like to explore.

Ether1 is a WAN interface, getting an address via DHCP and appears to be working as expected.
Ether2 is a master, with three tagged VLANs going through it and is serving separate DHCP for each VLAN
Ether3 is a master with one VLAN

In general, this all works. I can connect a device configured for the appropriate VLAN, get a local address and get internet by way of NAT. What is odd though, is my ping results. From any VLAN, I can ping the gateway/dhcp server for any other VLAN. I can’t ping any devices on the other VLANs, but it’s just odd that I can get at the gateway. Considering I’ve done no firewall or other configuration, is this normal? Should I fix it?

In more detail, this is what I’m after:
ISP
Routerboard
Wireless AP1
Client1
Client2
Client3
Wireless AP2
Client4

I have each client on its own VLAN for traffic shaping and filtering purposes. In addition, I’ll be implementing a VOIP network on another VLAN in the future. I want the Routerboard handing out the DHCP for these networks for management purposes, and I am not concerned about someone plugging in a rogue DHCP server.

Anyone mind helping me figure out why I can ping gateways for foreign VLANs? Secondarily, would you care to suggest alternate configurations or things I might have overlooked based on the short description of my goals?

**edit

Perusing other posts, I’m learning as I go. Current config as follows:

interface print

NAME TYPE MTU L2MTU MAX-L2MTU

0 R ether1-gateway ether 1500 1600
1 R ether2-master-local ether 1500 1598 2030
2 R ether3-master-local ether 1500 1598 2030
3 ether4-slave-local ether 1500 1598 2030
4 ether5-slave-local ether 1500 1598 2030
5 R 23900VLAN vlan 1500 1594
6 R 213VLAN vlan 1500 1594
7 R 12878VLAN vlan 1500 1594
8 R 21757VLAN vlan 1500 1594

ip address print
0 ;;; default configuration
192.168.88.1/24 192.168.88.0 ether2-master-local
1 192.168.10.1/24 192.168.10.0 23900VLAN
2 192.168.20.1/24 192.168.20.0 12878VLAN
3 192.168.30.1/24 192.168.30.0 213VLAN
4 192.168.40.1/24 192.168.40.0 21757VLAN
5 D 192.168.2.111/24 192.168.2.0 ether1-gateway
6 X 72.11.15.3/29 72.11.15.0 ether1-gateway

ip route print
0 ADS 0.0.0.0/0 192.168.2.1 1
1 ADC 192.168.2.0/24 192.168.2.111 ether1-gateway 0
2 ADC 192.168.10.0/24 192.168.10.1 23900VLAN 0
3 ADC 192.168.20.0/24 192.168.20.1 12878VLAN 0
4 ADC 192.168.30.0/24 192.168.30.1 213VLAN 0
5 ADC 192.168.40.0/24 192.168.40.1 21757VLAN 0
6 ADC 192.168.88.0/24 192.168.88.1 ether2-master-l… 0

ip firewall nat print
chain=srcnat action=masquerade out-interface=ether1-gateway


Based on other posts, it looks like it would be normal to have access to other VLANs through the RB. Sooo, in order to isolate them, I need some firewall rules. I’ve seen a few related examples intended to be copied and pasted in the CLI. First, can I do it through winbox? Second, is there a more straightforward or complete way than punching in the subnets for each VLAN over and over? I see in winbox at the firewall rule config screen there’s a checkbox in front of some of the options (eg. Dst. address) Clicking the box shows what looks like an exclamation point, sometimes known as NOT. Can I use this to say “drop all packets headed TO this interface NOT from the WAN” or some such?

By default the RB will pass all traffic between all connected subnets.

So you do need to add firewall rules to drop the traffic.

You add filter rules in IP → Firewall
You can use the address lists and the not checkbox to make this easier.

You might like to look at some of the wiki articles which show you the basic firewall ruleset you should use:
http://wiki.mikrotik.com/wiki/Protecting_your_customers

Nick.