Host ID vs MAC Address

UNIX Solaris
1

Hi,

I've got a Sun Solaris machine with host ID (840f8e57) and MAC address (0:14:4f:f:8e:57), how do I:

  1. Write the MAC address in standard (IEEE 802) format, i.e. xx-xx-xx-xx-xx-xx? Do I need to add 0's before or after the 'f', i.e. 00-14-4f-0f-8e-57 or 00-14-4f-f0-8e-57?

  2. What is exactly the Host ID, and is it made somehow from MAC address? If yes, how? And if I have (83ED8561) as my host ID, what would the MAC address be?

Thanks in advance.

2

Any idea regarding this?

3

The hostid uniquely identifies a given server. It is often used for software licensing.

Traditionally, a Sun server hostid was based on the MAC address of the primary on-board network interface. All network interfaces have a unique MAC address and Sun Microsystem's all begin with 08:00:20:xx:xx:xx. By truncating leading zeros your would get 8:0:20:xx:xx:xx displayed by ifconfig(1M).

The hostid starts with "80" -- the first two octets of the MAC address -- followed by six hexadecimal characters representing the last three octets. Thus, a server with a MAC address of 08:00:20:0a:1b:2c would have a hostid of 800a1b2c.

I believe with the newer servers, this is all being done away with and is supported by a "system configuration card" allowing you to take all of this information from one server to another in the event of a major hardware failure.

4

Thanks a lot for your reply.

As I understand from your post is that there is no way to get MAC address from Host ID, as there is always a missing part; hope I'm not mistaken.

By the way, the examples I used ini my first post are not imaginary examples, they are from real Sun Blade machines... I noticesd that the Host ID always starts with '8' (not '80') and ends (i.e. last 6 characters) with the last 3 octets of the MAC address :slight_smile:

Thaks again

5

As I said, I'm working with old hardware. The algorithm has probably changed. It seems from you example that Sun is still using the last three octets of the MAC address but that the first two digits are generated differently.

The easiest way to get a server's hostID is to use the command hostid. Sometimes simple is better.

:slight_smile: