Mac Address Puns

Hi All,

We got a Dell C6400 chassis with 4 ESXi blades. In our configuration each blade has 2 uplinks going to nexus5k switches or his FEX extenders. The 2 ports in the switch for each blade configured as trunk ports. We couldn't see the blades physical nic MAC addresses on the switch side, just the vm's that located on them. Is there a way to locate the physical uplinks nic MAC addresses on the switch side and not just the vm's?

Your help would be appreciated.

Reading this fine story reminded me of a similar tale from my own career, although I was not the newbie who saved the day and embarrassed the grey-beards.

I was working for a prepaid charging systems vendor, and our product used a Lucent Excel switch to trunk in the voice calls, gate them for charging, and switch them back out to the network. These are semi-intelligent devices which link to a server and essentially one-to-one map the incoming SS7 signalling messages from the network to an IP protocol which the server then processes however and replies to.

Physically it's a chassis with a back plane and a bunch of cards. Two are the CPU controller cards and the rest can be various types. The CPU cards get their IP addresses using RARP via rarpd running on the server.

One day, the customer noticed that one of the production CPU cards was showing down. No problem, we pulled one from the test system to put in production, and put the suspect production card into test.

Now, practically the only way to fuck the CPU cards up is to put the wrong MAC address in the RARP config file. So I was very careful in updating the production configuration when I put the known-good CPU card from test into it. I was also very careful in updating the test config so that we could check the suspect card.

Annoyingly, the test system card immediately failed when inserted into the production chassis and the production card immediately sprang to life in the test system. Just to be on the safe side, I told my more-senior colleague about the issue - he immediately asked if I'd updated the MAC addresses, didn't believe my answer, checked them himself and agreed they were correct.

So there's only one thing it can be - a failed back plane in the chassis. And this means we have to get a replacement in from Lucent as we don't carry those spare because ... well, they never fail, and they're worth about $100K each.

The new chassis arrives. I've got a new starter who's going to be a permanent on-site resource for the customer so to baptise him I tell him he's going to be doing the swap out.

Outage window arrives and he removes all the cards from the old chassis, removes the chassis, and puts the spare in. Before beginning to reinsert the cards, I warn him: the plug & slot design is lousy and it is incredibly easy to bend a pin putting the cards in. Forewarned, he takes

We just moved into a new apartment yesterday and we have community wifi. With this type of wifi you need the MAC address of a device to connect it if that device does not have a browser. Where can I find the MAC address to my echo so I can connect it?

Can someone help me interpret this log....does it mean my hardware is failing? Many thanks.

Apr 27 07:52:08	php-fpm	62568	/rc.linkup: The command '/usr/sbin/arp -s '192.168.3.10' 'c8:2a:14:55:03:95'' returned exit code '1', the output was 'arp: writing to routing socket: Cannot allocate memory'

Apr 27 07:52:08	php-fpm	62568	/rc.linkup: The command '/usr/sbin/arp -s '192.168.3.133' 'b8:ac:6f:0e:82:b0'' returned exit code '1', the output was 'arp: writing to routing socket: Cannot allocate memory'

I have static ARP entries for these two machines - perhaps that is the issue?? I do not see this error for any other machines on my LAN, just these two.

Need help find the MAC address of my hue hub

https://preview.redd.it/lx4s7rew2wy61.jpg?width=1536&format=pjpg&auto=webp&s=af27d7791fee7c660bcba9f8a0cbd99c0b89a92a

Hi everyone,

As the title says I'm looking for an IPTV app for an Android Box (Mi Box S) that would allow me the change the MAC address.

I tried Stalker on Kodi but it doesn't seem very stable.

Thanks!

Just purchased 8 x new generation LIFX Colour (1000 Lumens aka "LIFX Colour 1000lm").. noticed the MAC addresses are all off by 1 on them and the new generation LIFX+ A60.

In the LIFX app the serial numbers match the labels and the hostname and the default setup access point (BSSID) the bulbs broadcast.. but the MAC address the new generation bulbs actually use are the serial number + 1.

How did I notice? Simple, I was setting up DHCP leases and noticed the bulbs weren't claiming them.

Am presuming it's the device firmware (v3.70) not using the right MAC address rather than the physical factory labelling, hostname, access point name and broadcast serial numbers all being incorrect.

LIFX Hostnames vs MAC Addresses in Ubiquiti UniFi Admin Portal

Hello,

I am observing some MAC address changes upon power outage in example, and I am not sure what is causing it. It is breaking my IP binding.

My understanding is that MAC address is not something that should be changed.

Have anyone observed behavior such as this ?

I have following setup:

pfSense box

Unifi Switch with POE powering up 1 Unifi NanoHD

ps: I am not talking about mobile devices, its some sensors, zigbee hub and etc.

First I made a cron job on my OpenWRT router that runs ever 20 seconds... this is some horrible shell scripting, but it works :) You'll need to create a Long-Lived Access Tokens on your HA's /profile page. Use that and replace the "get_your_token_from_your_home_assistant" part below with your token.

You'll probably need to tweak "br-lan" and the IP address of your Home Assistant "192.168.1.2:8123"

#!/bin/sh

# Posts an event to Home Assistant when new devices are found on the network. This needs curl to run. Install it with:
# opkg update
# opkg install curl

arr=$(ip neigh show | grep br-lan)

# We use the file system to keep track of devices we know about. It works as a good hash map :)
# Write to /tmp/ since /tmp/ is a ramdisk. Only read/write to ~/history when needed since that's a read/write to the SD card

if [ ! -d "/root/history" ]
then
  mkdir -p /root/history
fi
mkdir -p /tmp/history

IFS=$'\n';
for line in $arr; do
  # Example line looks like:
  # 192.168.1.84 dev br-lan lladdr c3:0b:32:1a:b9:21 READY
  ip=$(echo "$line" | cut -d" " -f1)
  mac=$(echo "$line" | cut -d" " -f5)
  for id in "$ip" "$mac"
  do
    if [ ! -f "/tmp/history/$id" ]; then
      touch "/tmp/history/$ip"
      touch "/tmp/history/$mac"
      if [ ! -f "/root/history/$id" ]; then
        touch "/root/history/$ip"
        touch "/root/history/$mac"
        log="$line $(nslookup  $ip | grep name | cut -d"=" -f2)"
        echo "Found new device: $log"
        curl -X POST \
          -H "Authorization: Bearer get_your_token_from_your_home_assistant" \
          -H "Content-Type: application/json" \
          --data '{"log":"'"$log"'"}' \
          http://192.168.1.2:8123/api/events/new_network_device
      fi
    fi
  done
done

This posts the "new_network_device" event with the "log" data. So in Home Assistant I create an automation that sends a notification when that event is fired...

alias: New network device found
description: Sends a notification when a new device is found on the network
trigger:
  - platform: event
    event_type: new_network_device
condition: []
action:
  - service: notify.my_mobile_device
    data:
      message: 'A new device was found on the network: {{ trigger.event.data.log }}'
      title: New device found
mode: single

That's it! Nothi

If I’m not mistaken that feature was there in the iOS 14 beta it randomizes the private MAC address every 24 hours so I’d like to have that as a tweak

Is there a way to detect the original MAC address even after spoofing? I'm talking about a situation a device can be tracked everywhere when it logs onto a server using mac.

I found a thread on stack overflow dated in 2012 how to detect the original mac address after it has been spoofed, someone claimed in the reply that he has succeeded in doing so using his code. Not sure how valid it is.

I am trying to get into my parents router through aircrack-ng (obviously asked them first), many tutorials suggest deauthing is the first step but aircrack-ng requires the mac address of the AP you want to deauth, how can I get it without knowing the wifi password?

Starting at least 10 days ago (maybe longer), when most of our Mac Outlook users send an email, the FROM field contains their O365 username instead of the primary SMTP address on their mailbox. Only a handful have noticed so far, but when I started reviewing the message trace logs for all Mac users, it's clearly a much wider problem. Has anyone else encountered this problem yet?

All of these mailboxes are hosted in Exchange Online, and messages sent from any other client (OWA, Outlook Mobile, etc.) correctly show the sender's primary SMTP address in the From field. So this would seem to be an issue with the Mac Outlook client. The configuration is pretty simple, and these were all working perfectly until recently. I've had a support case open with Microsoft since Monday, with very little to go on so far. Any advice would be appreciated.

Thanks!

Goodevening, so I'm using an Ethernet Shield for a project and I assigned a MAC address to the board. I put an if that controls if the MAC address is == 0, if it is it says "Failed connection".

The error occurres every time I execute the code so it blocks the execution after 10 lines. What could be the problem?

Is there a way to detect someone's real MAC address even after spoofing (from the ISP's side)?