#Vm vsphere for mac registration#
#Vm vsphere for mac mac#

The raw data needs cleaning up before it can be used, but that’s straightforward enough using PowerQuery. As demonstrated by the output from running the command on a CentOS server, it attempts to resolve the IP addresses to a fully qualified domain name and provides interface details within the same table.

#Vm vsphere for mac mac#

The output of the same command on a windows server will for example provide you with and IP address, MAC address and entry type (static or dynamic) and divides the output up on a per interface basis.

#Vm vsphere for mac registration#

How can this be used practically? Well if we had access to a table of say every MAC OUI Registration combined with say the output from an ARP (Address Resolution Protocol) command then we can very quickly build up a picture of what hardware is on a network.Īs a quick example I’ve downloaded the MAC OUI registration information from the link above and then combined that with the output from an “ arp -a” command that I ran on a CentOS server in a lab environment.Īrp is not a command that is created equally across all operating systems. This means our vCenter Server Unique ID is 22 Multiply the third to last digit by 16, so 1 x 16 = 16 (for a longer Hex number then multiply the fourth to the last digit by 16 x 16 x 16, Multiply the fifth to the last digit by 16 x 16 x 16 x 16 and so on until all the digits are used).Īdd up the outputs from above, so 6 + 16 = 22 Multiply the last digit by 1, so 6 x 1 = 6 To convert the hex number 0X16 to decimal we need to follow these steps: Next step is to rebase 0x16 from Base-16 to Base-10, or convert 0x16 to decimal, now i appreciate that’s probably not an everyday operation. Then we subtract 80 from that which looks more complicated than it is 0x96 – 0x80 = 0x16. Working out the vCenter ID requires taking the 4th octet in the example above that would be the forth octet from 00:50:56:96:a4:e5, which is 96. Taking the example MAC address in the image, listed as 00:50:56:96:a4:e5 we can work out the virtual centre that this virtual machine belongs to.Īccording to the VMware OUI allocation scheme, a MAC address has the format of 00:50:56:XX:YY:ZZ, where as discussed above 00:50:56 represents the VMware OUI, XX or the forth octet is calculated as 80 + vCenter Server ID, and YY and ZZ are random two-digit hexadecimal numbers. We can take this a step further with VMware MAC addresses. Unless you are dealing with much older VMware infrastructure the only one worth really committing to recall is 00:50:56. I knew the MAC address 00:50:56 was a VMware virtual machine because 00:50:56 are assigned to VMware as MAC address Organisational Unique Identifiers (OUI). The first three pairs of a MAC address is granted to a vendor or manufacturer. Example VMware Virtual Machine MAC Address