4 ms·
Ask HN: How to ensure reasonable entropy in Linux?
So today I am trying to install FreeIPA in a VM on Proxmox VE. Neither the hypervisor nor the guest seem to have sufficient entropy to complete the install, per the developers. On advice from IRC, I found out how to check entropy using 'cat /proc/sys/kernel/random/entropy_avail'.
Results:
- desktop: 1456
- hypervisor: 262
- guest: 94
Suggestions I've seen so far are:
1. Implement VirtIO-RNG for my VM. This would share and throttle the hypervisor's /dev/random with the guest. This does little good IMHO, if even the hypervisor is starved of entropy. http://wiki.qemu-project.org/Features-Done/VirtIORNG
2. haveged - "A simple entropy daemon"; Any thoughts on this? http://www.issihosts.com/haveged/
I would enjoy having a hardware RNG, but I wonder what software can do to solve this issue.
https://en.wikipedia.org/wiki/Comparison_of_hardware_random_number_generators
I seem to remember the random numbers as a service post about the NIST recently. Is that worth looking into for this?
- jlgaddis 13y agohaveged seems to work quite well and, before I started using it months ago, I ran some of its output through dieharder, ent, etc. There's also rngd which can also use the RNG in a TPM, if one is available.
- josh-wrale 13y agoThanks, that is helpful. I found the story of how haveged came to be, which was a surprise: https://www.centos.org/forums/viewtopic.php?f=25&t=31111 https://www.centos.org/forums/viewtopic.php?f=25&t=31111 I also found this. The answer for most part speaks to havege instead of haveged. The last part of the answer speaks to haveged. https://crypto.stackexchange.com/questions/8083/quality-of-randomness-on-a-linux-system-with-haveged https://crypto.stackexchange.com/questions/8083/quality-of-r...
- josh-wrale 13y agoWishing nerdy stuff like this would get more upvotes.. :)