Access to cable modem status page

RouterOS Beginner Basics
1

I’m scratching my head trying to figure out how to get access to my cable modems status page (which uses a fixed private LAN address of http://192.168.100.1) but is on the external side of the router. I’m not sure if the problem is a missing/conflicting route(s), or one of the firewall rules, or …

I’ve got some networking experience but it’s been maybe 12 years since I was configuring Cisco routers routinely so I’m very rusty.

The router is a RB750G upgraded to RouterOs 5.5 and with fairly minor tweaks (e.g. disabling unneeded packages (hotspot, ppp, mpls) and setting my own address range for ether2-local-master and the DHCP server) to the standard out of the box configuration.

Thanks…

2

See if you could ping 192.168.100.1 from your router. If you can, which you should, since it would be a strait cable in between, then probably there is no route on your cable modem pointing to ip of the interface on the internal side of your mikrotik.

3

i did this. just add 192.168.100.2 to your external interface. i cant remember if i needed a srcnat rule as well … depends if your modem has any route tables in it or not.

4

Ah, multi home the external interface, presumably with a tight mask (e.g. 192.168.100.2/30)? Very clever, I’ll have to try that.

I was thinking along the lines of a point to point route but struggling with how to define it properly.

I’m scratching my head over how this worked with the old LinkSys router, and all I can figure is that instead of routing to a specific upstream destination it just blindly routed anything that was outside the internal address space through the uplink port.

5

Could you post your relevant srcnat rule(s) if any? Thanks…

6

did you try without it?

add action=masquerade chain=srcnat disabled=no dst-address=192.168.100.0/24

either that, or action=accept so that it doesnt nat it. you could also use src-nat and to-address=192.168.100.2 so that anything going to that IP doesnt get natted. I am pretty sure I didnt even need that, the modem just returned the traffic autoamtically.

7

PEBCAK. :blush: Terribly sorry… :frowning:

While setting up the router and changing the addresses from the default 192.168.88.0/24 net to match the rest of my systems, I opened up the net mask to /16 and added a secondary address of 192.168.88.2 for eth0:0 on my Linux workstation. So the gateway never even got the packets to route…