Debian Edu ran into this problem when installing Kerberos as a server from d-i, and solved it by running a process in the background to monitor the entropy level, and when it was running low, it would flush the file buffers and run 'find /target' to force some IO operations that would add entropy to the kernel.
The code can be found in <URL: https://salsa.debian.org/debian-edu/debian-edu-config/blob/master/share/debian-edu-config/d-i/finish-install > and look like this: # Try to add entropy when running low ( cd / while true ; do entropy="$(cat /proc/sys/kernel/random/entropy_avail)" if [ 130 -gt "$entropy" ] ; then log "low on entropy, pool is $entropy. trying to add more" # Disk IO add entropy to the kernel. Flush cache to ensure find and # touch/rm causes disk IO. sync echo 3 > /proc/sys/vm/drop_caches find /target > /dev/null || true touch /target/var/tmp/foo sync rm /target/var/tmp/foo sync entropy="$(cat /proc/sys/kernel/random/entropy_avail)" log "entropy pool is $entropy after trying to add" fi sleep 20 done ) < /dev/null 2>&1 3>/dev/null 4>&3 5>&3 6>&3 | logger -t edu-entropy-add & epid=$! ... install stuff ... # Ignore errors in case the entropy gathering is no longer running if kill $epid ; then : else log "error: killing the entropy gathering job failed - exited?" fi Perhaps a similar approach could be inserted into the default Debian Installer? -- Happy hacking Petter Reinholdtsen