As I recall, network devices are not enabled to inject entropy
and if one is netbooting a headless box (not all that uncommon)
I do not believe there is anything else available for entropy.
I had noticed the same thing back when I was experiencing the
'long sleep' on DSA generation...  Cheers,  -- Ken

Anders Magnusson wrote:

> > However, it appears that none of the device drivers on the vax
> > have been instrumented to inject entropy into the randomness
> > pool, at least I find no bits on the NetBSD-1.5_BETA2 vax system
> > I have access to, so all the entropy you get from /dev/random
> > will be pseudo-random bits.  (Someone should probably fix that...)
>
> Hopefully the MI drivers the VAX port uses (if_le, ncr53??, ...)
> have support for rnd, and those are the drivers most common VAXen uses.