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Re: hostid gives identical values on all FC machines

Matthew Saltzman wrote:
But MAC address is not bad (though, of course, anything can be forged with
more or less effort).  Solaris generates the hostid from the MAC address
of the primary NIC.

If we are talking about Sparc machines, the above statement is not true. Sparc has actual hostid stored in PROM chip. Hostid is stored in bytes 1, c, d and e, while MAC address is stored in bytes 2-7 of this chip. Byte 1 of hostid is machine type (don't touch it), and the remaining three bytes (also called serial number) you can set to preatty much anything you want. Hostid command will simply read out those bytes form PROM chip and display them on the screen. MAC address is sometimes set to be identical to hostid, but it can be different (not stored in same location on the chip). You can also set it to preatty much anything you want (but some Sun boxes will complain if first three bytes are not set to 08:00:20). Don't forget to recalculate and store new checksum into byte f, or you'll be in deep poop.

Luckily, there's port of Fedora Core for Sparc machines, which makes the above not totally off topic ;-)

Aleksandar Milivojevic <amilivojevic pbl ca>    Pollard Banknote Limited
Systems Administrator                           1499 Buffalo Place
Tel: (204) 474-2323 ext 276                     Winnipeg, MB  R3T 1L7

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