CRS125-24G-1S-RM Configuration

RouterOS Beginner Basics
1

After successfully setting up a Mikrotik wireless access point, I decided to take the plunge and finally replace my apple time capsule as my router/switch with a CRS125-24G-1S-RM.

So far, I have renamed every port ether1-ether24…I have then created ether1 as its own master and then ether2 as its own master with ether3-ether24 as slaves of ether2. I have created a working dhcp server on ether2…192.168.5.0/24 is the address space.

What I want is for ether1 to be the WAN port. It will be a dhcp client to get its IP address from comcast.

Right now, ether1 still has the IP address of 192.168.88.1…I set up a bridge and can now ping from 192.168.5.1 to 192.168.88.1 and vice versa. Instead of a bridge should I use a static route?

I am trying to use ROS code as much as possible. I dont particularly like the webfig.

Would someone be able to explain how I create a static route from ether2 to ether1?
Also how do I create reservations for my appletv, timecapsule, tivo, etc. The addresses being handed out are 192.168.5.100-1092.168.5.254

Eventually, I want to have the following
ether1 - WAN
ether2 - DMZ 192.168.4.0/24
ether3, ether4, ether5 - Wireless Access Points 192.168.6.0/24 → 1 wlan for house occupants plus 1 wireless vlan for guests - 192.168.7.0/24
Ether6-24 -Wired LAN 192.168.5.0/24

Thank you for your help.

2

Hi,

I have RB951-2n but I think this should apply to your device as well.

If you don’t like Webfig, you can try WinBox http://download2.mikrotik.com/routeros/winbox/3.0beta3/winbox.exe

I’m not sure, that you should set ether1 as the master port of ether1, I think that the option “none” is good enough.

You can add, disable or remove IP addresses of the individual interaces from IP → Addresses so if the ether1 has an IP address you don’t want, you can go there and delete the wrong address. I would also remove ether1 from all bridges (this can be done in Bridge → Ports). You can add DHCP Client to an interface from IP → DHCP client.

Be careful with bridges - if you add all ports to a bridge and leave that bridge without an IP address, you won’t be able to log in (maybe not even using a MAC address) and you’ll have reset your router settings

In my RB951-2n routes between interfaces are created automatically so if I assing IP address 192.168.2.1/24 to ether2 and 192.168.3.1/24 to ether3 RouterOS will create routes to subnets 192.168.2.0/24 and 192.168.3.0/24 automatically.

I guess you’ll just have to add the default gateway (destination address 0.0.0.0/0) manually.


Post a reply if you make some progress. :wink: :wink:

3

I really wish the CRS125 had the Quick Config like the RB951. Would make life easier for people learning ROS.

^This is correct.

Don’t remove the address you’re connected to via Putty or WinBox or you’ll lose access and have to reconnect via MAC or another interface’s IP address.

I don’t know how many times I did this when configuring my CRS. If you configure a bridge make note of the Admin MAC Address. I’m not sure how it is determined what that address is. I think it may be the MAC of the first port assigned to the bridge. This is where that LCD screen on the CRS can come in handy since you can look up the MAC of the ports.

I suggest familiarizing yourself with WinBox. The ability to connect via MAC address can be quite useful as is the SAFE MODE feature.
Knowing how to do things from the command line is useful too and sometimes faster (like renaming ports en-masse. You can use Excel to quickly increment the interface numbers and the concatenate function to build the full command and then copy/paste into the command window.).

Not sure how much of the default configuration you’ve changed but by default ether1-gateway has a DHCP-Client already configured (as does the SFP-Gateway). Verify from ROS command line:

ip dhcp-client print

If it is already there then you should be good to go. To avoid having to manually create the default route ensure the following option is set:

add-default-route=yes

If it isn’t then you can enable it with:

ip dhcp-client 0 add-default-route=yes

If there is not a DHCP-Client on ether1:

ip dhcp-client add interface=ether1 add-default-route=yes

I also suggest manually specifying your own DNS servers:

use-peer-dns=no




ip dns edit servers

and add DNS server IP’s separated by commas.

To exit the editor:

CTRL+o

I recommend changing the name of ether1 to “WAN” for ease of identifying it:

interface ethernet set ether1 name=WAN

Next you’ll need to verify NAT. By default ether1-gateway should have a NAT rule for masquerade. To check:

ip firewall nat print

If it isn’t there:

ip firewall nat add chain=srcnat action=masquerade to-addresses=0.0.0.0 out-interface=WAN
4

Ok I am finally revisiting my CRS125. I reset the settings and have started over.

I have renamed all the ports ether1-ether24. ether1 doesnt have a master port and i left the 192.168.88.1 IP address. ether2 is the masterport for ether3-ether24. ether2 has an IP address of 192.168.5.1

ether1 is the WAN port but it is named ether1 with the IP address of 192.168.88.1 is supposed to be a DHCP client for Comcast for my connection to the outside world. So I should type this command “/ip dhcp-client add interface=ether1 add-default-route=yes use-peer-dns=yes”

I have a dhcp server running on ether2 (LAN port) assigning addresses in the range of 192.168.5.100 - 192.168.5.254. I used CLI wizard for this. What should DNS be?

I don’t understand what I command(s) I need to run to get traffic from inside to outside and back again.. I need a route, correct?

For NAT, I think I need to run this command /ip firewall nat add chain=srcnat out-interface=outside action=masquerade

I found this link … http://wiki.mikrotik.com/wiki/How_to_configure_a_home_router …should I follow that? I’ve been trying to use the cli.

5

I am not real able to find “wlan1” or anything like that below wireless tab everything is empty. Can you please help me to setup wireless ap for my mikrotik hotspot.
Thank you!