Changing from bridge to router mode via Command Line?

RouterOS Beginner Basics
1

Hi All,

I have a Mikrotik CRS312-4C+8XG (running 7.14.2) which is currently in bridge mode (as viewed from the “Quick Set”). I would like to switch it to router mode. Theoretically - easy enough from the “Quick Set”. However, I’m concerned about two primary issues …

  • WHAT does it actually change in the configuration to effect this?


  • HOW do I switch it back via the CLI if I needed to (my failsafe is Serial Console or the WiFi woobm/terminal)

I have spent a considerable amount of time trying to determine the answer to both of these things and not found any relevant information related to.

With the first - my concern is I have a fairly involved set of bridge interfaces, vlan topologies, etc … and would like to preserve them - just enable Layer 3 routing between them.

Yes - I have full backups. :slight_smile:

Much appreciated for any input or pointers on what I’ve missed in my digging around so far.

~~shane

2

I don’t think it’s possible to switch between Router and Bridge mode or do whatever Quickset configuration on the CLI because, as the name suggests, it is a menu to set up quickly and easily configuration. What Router mode essentially does is that it removes ether1 from the bridge and adds masquerading NAT to it. Reference:

http://forum.mikrotik.com/t/exact-difference-between-router-and-bridge-mode-of-mikrotek/63955/3

3

@TheCat12 - thank you for the response and pointer …

Fortunately … it turns out I was barking up the wrong tree. Corp IT installed new routes in our VPN solution which were conflicting with our internal lab networks. :frowning:

4

There’s nothing QuickSet can do that you cannot do from the CLI.

The only tricky bit is doing it in a single step without locking yourself out. For this, you have to rely on RouterOS’s CLI scripting syntax, using square brackets to prevent early changes from taking effect before you’ve finished typing the full set of commands needed to transition the device from one mode to the other:


> [      
[... :put hi
[... :put bye
[... ]
hi
bye

Notice that we don’t get the requested output until we hit Enter after the right square bracket. This is the behavior we will rely on.

To get from the stock “bridge” to “router” configurations on a CRS class device in a single step like QuickSet does, you can say something like this:


[
  /interface list add name=WAN
  /interface list member remove list=LAN interface=ether1
  /interface bridge port remove bridge=bridge1 interface=ether1
  /interface list member add list=WAN interface=ether1
  /ip dhcp-client add interface=ether1
  /ip firewall nat add chain=srcnat out-interface-list=WAN action=masquerade
  /ip firewall filter add … all kinds of stuff …
]

This presumes the “LAN” interface list already exists and had all the bridged interfaces in it already, and that ether1 is the one you want being the WAN interface.

This is all based on my guide to the default RouterOS configuration, which describes the router case, being more complicated than the bridge case, so that for the most part, I only needed to add new things in my example above, not change existing ones.