Used LB4M – Finding the Management Interface

Used LB4M – Finding the Management Interface

I bought an LB4M on ebay. I did not have a USB to RJ45 console cable.

Power port – Green
Status port – Orange

I read online that by default the management port pulls an IP via DHCP but that wasn’t working. I cycled through several ports on the device connecting them to my network and actually missed that one port pulled an IP address.

I then connected my laptop to the management port and watched traffic with Wireshark. The LB4M was sending data using the CDP protocol (new to me).

So the firmware is 1.1.0.8. Understanding the span of features vs stability for LB4M firmware versions seems to be a minefield.

The packet data indicated that it had picked up (or statically held) an IP on some interface. As I plugged in ports I ran:

$sudo nmap -F 192.168.1.215
Nmap scan report for 192.168.1.215
Host is up (0.010s latency).
Not shown: 99 closed ports
PORT   STATE SERVICE
23/tcp open  telnet

I was in.
Username: admin
Password:

My first experience with this CLI, so lets poke around.
(type show ? for options)

(Switching) >show network

Interface Status............................... Up
IP Address..................................... 192.168.1.215
Subnet Mask.................................... 255.255.255.0
Default Gateway................................ 192.168.1.1
Burned In MAC Address.......................... XX:XX:XX:XX:XX:XX
Locally Administered MAC address............... 00:00:00:00:00:00
MAC Address Type............................... Burned In
Configured IPv4 Protocol....................... DHCP
Management VLAN ID............................. 1
(Switching) >show serviceport

Interface Status............................... Up
IP Address..................................... 0.0.0.0
Subnet Mask.................................... 0.0.0.0
Default Gateway................................ 0.0.0.0
Configured IPv4 Protocol....................... None
Burned In MAC Address.......................... XX:XX:XX:XX:XX:XX

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