Munin "Available entropy" when using address space layout randomization

Posted by clawspoon on Super User See other posts from Super User or by clawspoon
Published on 2010-03-14T21:40:50Z Indexed on 2010/03/14 22:05 UTC
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linux

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entropy

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munin

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random

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linux-kernel

Having just configured munin for statistics logging on my gentoo server (hardened profile), I am noticing that my "Available entropy" is consitently in the 200-300 range. This seems way to low, so I checked it manually using the command

$ cat /proc/sys/kernel/random/entropy_avail
3544

Odd. Consistently very low values in Munin and practically filled up when checking manually. After thinking about the problem for a while I came to the conclusion that the problem is probably that I'm using Adress Space Layout Randomization which is using the entropy when running commands/programs. Since Munin runs a whole slew of programs all the entropy is used up, and Munin then measures how much entropy there is, resulting in the low values.

Does anyone have any experience with this? How can this be avoided?

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