CPE and issue with resceving an IP

RouterOS Beginner Basics
1

Hi

See image below for my setup.
home network overview.png
The issue is the clients connecting over the 951 is not getting any IP from the DHCP server, the logs show this:

defconf offering lease 192.168.88.82 for 10:9C:70:0E:04:1B to 4C:5E:0C:39:D0:39 without success

Here is the config on the 951:

# may/14/2023 13:48:28 by RouterOS 6.48.6
# software id = B1AY-NRL9
#
# model = 951G-2HnD
# serial number = 4F430477A66A
/interface bridge
add name=bridge1 protocol-mode=none
/interface ethernet
set [ find default-name=ether1 ] speed=100Mbps
set [ find default-name=ether2 ] speed=100Mbps
set [ find default-name=ether3 ] speed=100Mbps
set [ find default-name=ether4 ] speed=100Mbps
set [ find default-name=ether5 ] speed=100Mbps
/interface wireless
set [ find default-name=wlan1 ] country=sweden disabled=no installation=\
    indoor mode=station-pseudobridge ssid=******* station-roaming=enabled \
    wireless-protocol=nv2-nstreme-802.11
/interface wireless security-profiles
set [ find default=yes ] authentication-types=wpa-psk,wpa2-psk group-ciphers=\
    tkip,aes-ccm mode=dynamic-keys supplicant-identity=MikroTik \
    unicast-ciphers=tkip,aes-ccm wpa-pre-shared-key=********* \
    wpa2-pre-shared-key=*********
/user group
set full policy="local,telnet,ssh,ftp,reboot,read,write,policy,test,winbox,pas\
    sword,web,sniff,sensitive,api,romon,dude,tikapp"
/interface bridge port
add bridge=bridge1 interface=wlan1
add bridge=bridge1 hw=no interface=ether1
add bridge=bridge1 hw=no interface=ether2
add bridge=bridge1 hw=no interface=ether3
add bridge=bridge1 hw=no interface=ether4
add bridge=bridge1 hw=no interface=ether5
/ip dhcp-client
add disabled=no interface=bridge1
/ipv6 nd
set [ find default=yes ] advertise-dns=no
/system clock
set time-zone-name=Europe/Stockholm
/system package update
set channel=long-term
/system routerboard settings
set auto-upgrade=yes cpu-frequency=700MHz
#error exporting /user aaa
#interrupted

Any suggestion to what I might be doing wrong here?

2

Anyone? Is there anything that is unclear in my setup or question that I can clerify?

3

You could try using the wireless repeater feature and then adding the ethernet ports to the bridge that got created.

See this thread Bridge an existing Wifi to LAN

4

There are limitiations due to the 802.11 protocol which station-pseudobridge only partially addresses, see https://help.mikrotik.com/docs/display/ROS/Wireless+Station+Modes.

With the AP and station both being Mikrotik the preferred option would be station-bridge which implements vendor-specific transparent L2 bridging. Unfortunately Mikrotik do not support this with CAPsMAN, only when the APs are configured manually.

5

Hmm, so after testing, some I set it up as a PTP Brdige CPE (quick set) connecected it to the wifi and tested by hooking up my computer to eth2.

Behold and my computer gets an IP, I have access to my home network servers and so on (yes I disabled the wifi on the computer).

I disconnect the computer and connect the 3d printer and I’m back with the same issue as before, it can not get an IP from the DHCP server:

	defconf offering lease 192.168.88.36 for 10:9C:70:0E:04:1B to 4C:5E:0C:39:D0:39 without success

So it seems now to be an issue between the printer and mikrotik and not the implementation itself?

6

First thing I would try is click the “always broadcast” in the dhcp server. See this post for what I mean. Probably won’t change anything, but it is easy to do and undo.

If that makes no difference, then more troubleshooting/testing will be needed.

If you connect the printer directly to a port on a MikroTik running a dhcp server does that work?

I.e. if you have long cable you can run between hap and the printer, or temporarily move the hap to the room with the printer, or setup the 951G-2HnD with a dhcp server and see if the printer then gets an IP address, at least we could determine if it was an issue with the wireless or the dhcp.

I know there were versions of UniFi UAP firmware that caused problems when used with non-UniFi routers (USG or UDM would work, but EdgeRouters, and other firewall products had problems). The reason I bring this up is that the wireless access point can cause problems for some dhcp servers while still working with others.

7

Has the printer ever been able to obtain an IP address with dhcp from any dhcp server?

8

The printer was connected over wifi, and got an IP from the DHCP that way. But the wifi is slow and unstable now that the printer is moved in to the closet. So the idea was to improve the built in ESP01 by connecting it over and 951 I had over from earlier days…

Well turning the “always broadcast” option did not help, same error in the logs as before. I will try to connect it directly somehow, just need to figure out how.

9

Well I setup a DHCP on the 951 and the printer directly got an IP, so I decided to test to give it an IP in the same range as on my main network, 192.168.88.0/24 and now I can access it as I would expect. I would still love to solve my little problem, so I can manage all the configuration on the HAP, but for now I think I will focus on other problems unless someone has a great sugestion to what might fix the issue?

Thank you all for you help so far, I have managed to get it working, which is great even thou not as easy as I expected :slight_smile:

10

Ok, so I have upgraded my main capsman managaer to 7.12.1 and now I’m back and my little bypass does not seem to work anymore, anyone who knows how to fix this?

11

Hi,
I would probably do the following.

Leave the main network as is but set up the DHCP server to not assign devices to a part of it.
Remove Nat (if any) on the 951.

**Edit In interfaces interface lists, ensure the wlan is not a member of WAN (So No Nat, and other firewall rules),
and optionally make it a member of LAN if you want to access the router from the main Lan) **

Example will use 192.168.88.128/27 (128-159)
Move any statically devices on lan assigned within this range.

Setup the 951 with ip address=192.168.88.129/27 on its lan/bridge interface
Make the 951 dhcp server hand out dhcp in the range 192.168.88.130-192.168.88.158 with mask of /27.
dns=192.168.88.129
gateway=192.168.88.129

Then set proxy arp mode on the wlan interface of the 951 connected to the main Lan. ** important **

Should be job done.
All devices on main lan should be able to connect to devices behind 951.
They will arp for device in range .129-160, 951 knows it has them behind it, so it responds to arp request.
They send their packet to the 951, it forwards it to the device behind it.

Devices behind 951 should be able to connect to devices on main lan.
They will just go to their default gateway for devices out of the range 128-159.

(An alternative could be to configure dhcp server on 951 so devices behind the 951 think they are also on a /24 subnet,
and have proxy arp on the bridge of the 951, there are likely both advantages and disadvantages doing this)