---
title: "I have FreeBSD 4.x and \"rndc-confgen -a\" just sits there."
slug: "aa-00313"
description: "Use rndcontrol(8) to tell the kernel to use certain interrupts as a source of random events."
updated: 2018-10-10T14:37:18Z
published: 2018-10-10T14:37:18Z
canonical: "kb.isc.org/aa-00313"
---

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# I have FreeBSD 4.x and "rndc-confgen -a" just sits there.

/dev/random is not configured. Use `rndcontrol(8)` to tell the kernel to use certain interrupts as a source of random events. You can make this permanent by setting `rand_irqs` in /etc/rc.conf.

`rand_irqs="3 14 15"`

See also: [What does "no source of entropy found" or "could not open entropy source foo" mean?](https://kb.isc.org/docs/aa-00309)