Exim Entropy

While trying to get exim4 using TLS I noticed an odd problem. For some reason /dev/random was not generating a lot of output due to a lack of entropy. I do not fully understand the problem but it meant that exim4 was being blocked when generating the RSA key. I tried changing from a 2.4.32 kernel to a 2.6.16.27 kernel and this seemed to generate more random data but it still wasn’t sufficient.
I resorted to editing my
/etc/cron.daily/exim4-base
commenting out the last line that deletes
/var/spool/exim4/gnutls-params
I then ran
find / -type f | xargs cat > /dev/null
to generate a lot of noise on the system.
hal:~# swaks -a -tls -q HELO -s localhost -au harry
Password:
=== Trying localhost:25…
=== Connected to localhost.
EHLO hal.vm.bytemark.co.uk
<- 250-hal.vm.bytemark.co.uk Hello localhost [127.0.0.1]
<- 250-SIZE 52428800
<- 250-PIPELINING
<- 250-STARTTLS
STARTTLS

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