Re: Continuing /dev/random problems with 2.4

Ken Brownfield (brownfld@irridia.com)
Fri, 1 Feb 2002 13:52:25 -0600


On Fri, Feb 01, 2002 at 02:50:31PM -0500, Robert Love wrote:
| What is the output of `/proc/sys/kernel/random/entropy_avail' when
| programs are stalled? Is it actually 0?

Yep, and it never raises above that -- it doesn't jump around even after
a month.

| Can you see if any programs are perhaps draining entropy in the
| background? See what has /dev/[u]random open ... note even /dev/urandom
| uses entropy, its the same as /dev/random, except it doesn't care when
| the entropy estimate is 0.

I've scanned /proc to verify that all PIDs do not have an FD open to
/dev/random. This was my first guess when this started -- some
developer was draining entropy in a while(1) loop. I believe I went so
far as to go to runlevel 1 with nothing but sh and kernel threads.

That may not be comprehensive, so I'm open to other diagnostic tips.
And yes, /dev/urandom does continue to work, as expected.

Thanks!

-- 
Ken.
brownfld@irridia.com

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