Got ahold of used RouterBOARD 411U device -- is it bad?

Hi.

I recently managed to acqurie a used RouterBOARD 411U-based wireless access point device, and was seeing if I could make it work. I’ve never used this stuff before; this is my first time. I was hoping I could set this up to use as an external wireless device for giving a wireless connection to a server computer I have (which will be connected to a camera). I’ve been looking at some of the manuals to try and get to know the OS and to troubleshoot the problem I’ve having, but have had no luck. I want to determine if the hardware is OK, as I’m not sure it is.

The problem: I cannot seem to connect to the device via Ethernet. When I do a “# ping 192.168.88.1” from my LInux-running computer (not the server computer I intend to use this with), which it is plugged into (actually, it is plugged into a passive Power-over-Ethernet injector which is in turn plugged into the computer), I get this:

PING 192.168.88.1 (192.168.88.1) 56(84) bytes of data.
From 192.168.88.2 icmp_seq=1 Destination Host Unreachable
From 192.168.88.2 icmp_seq=2 Destination Host Unreachable
From 192.168.88.2 icmp_seq=3 Destination Host Unreachable
From 192.168.88.2 icmp_seq=4 Destination Host Unreachable
From 192.168.88.2 icmp_seq=5 Destination Host Unreachable
From 192.168.88.2 icmp_seq=6 Destination Host Unreachable
^C
--- 192.168.88.1 ping statistics ---
7 packets transmitted, 0 received, +6 errors, 100% packet loss, time 6031ms
pipe 3

In other words, I cannot ping the device. The device appears to be set for 192.168.88.1 IP address, so that doesn’t seem the problem. Using “arp” from the Linux machine shows

Address                  HWtype  HWaddress           Flags Mask            Iface
192.168.0.1              ether   00:11:95:1b:44:96   C                     eth1
192.168.88.1                     (incomplete)                              eth0

“eth0” is the network interface on the main computer set to the 192.168.88.x network. It is an on-the-motherboard “(Realtek) RTL8111/8168B PCI Express Gigabit Ethernet controller”, according to lspci on Linux. It is set to the IP address 192.168.88.2. Note that HWaddress for 192.168.88.1, which is the RouterBOARD device, shows as “(incomplete)”. This is what I’m puzzled by. Is its Ethernet subsystem bad?

I ran several tests from the MikroTik RouterOS side (it looks to run RouterOS 4.5) after logging in to the board via the serial port. First, ping to the Linux computer (192.168.88.2):

[admin@MikroTik] > ping 192.168.88.2                                            
192.168.88.2 ping timeout                                                       
192.168.88.2 ping timeout                                                       
192.168.88.2 ping timeout                                                       
192.168.88.2 ping timeout                                                       
192.168.88.2 ping timeout                                                       
192.168.88.2 ping timeout                                                       
7 packets transmitted, 0 packets received, 100% packet loss

So there’s a fail there.

Then, I try “monitor”, thinking that might work:

[admin@MikroTik] > /interface ethernet monitor ether1                           
            status: link-ok
  auto-negotiation: done
              rate: 100Mbps
       full-duplex: yes

Doesn’t look like anything seems to be wrong – says “link-ok”, and I don’t see anything that appears to be an error. I also tried “ip route print”, to look at the routing, to see if maybe there was a problem there:

[admin@MikroTik] /ip route> print                                               
Flags: X - disabled, A - active, D - dynamic,                                   
C - connect, S - static, r - rip, b - bgp, o - ospf, m - mme,                   
B - blackhole, U - unreachable, P - prohibit                                    
 #      DST-ADDRESS        PREF-SRC        GATEWAY            DISTANCE          
 0 ADC  192.168.88.0/24    192.168.88.1    ether1             0

Note that as I’m still new to this and just wanted to get it working as a wireless thingy, I’m not sure that these tests were exhaustive or whether they even would’ve tested for the right thing, but they seem like the usual things I’d do to test the network of my PCs.

Any ideas? Could this piece of kit be broken? Thanks.

I just tried powering the board through the power jack instead of the Power-over-Ethernet, leaving a direct cable to my PC and it seems to work OK that way. Could it be a cabling problem in how the Power-over-Ethernet thing is connected? If so, what?

if you actually powered up the router via PoE then most probably you plugged wires correctly, that might be problem with PoE injector as power over spare pairs is used and powering via ethernet should not cause any problems.

I think I’ve solved the problems now. I tried setting “mdix-enable” to yes and that seemed to make it work. I also discovered some connection problems (cable hadn’t seated properly) in the PoE injector. Thanks!