Re: generating a Linux WWN?

Jeff Garzik
2007-10-06T14:36:40Z

James Bottomley wrote:
> My problem with auto generated is that it's provably impossible to
> generate globally unique numbers for WWNs without some internal source
> of uniqueness (I know sparcs have this in their serial number, but most
> PCs unfortunately don't).
>
> I know the auto generated number can be statistically reasonably unique,
> but sysadmins are lazy people. If they run into this problem, they'll
> take the knob with the on/off switch rather than the think about the
> problem and specify the full WWN; and then, being busy people, they'll
> forget about it as "problem solved". When they do this, statistically
> (and probably years later) there will be a cluster reboot where the
> entire SAN simply collapses and no-one knows why ... the poor SAN
> administrator will likely spend weeks working out the problem is.

Why, if we give lazy administrators root access, that's all they'll use,
and they will just think "problem solved" until a serious security issue
arises that takes down the cluster.

See how silly and un-Linux that logic is? In Linux, the admin has the
power to make stupid decisions -- or to make informed decisions that
disagree your rigid "an admin should never do that" line of thought.
It's their hardware.

You're also using the 1% case of a 1% case of a 1% case to argue against
a feature that is useful in making things Just Work(tm).

Jeff