How to fix the entropy pool issue with RHEL 5.x

As has been pointed out, colocated servers, lacking that random human being to create entropy, generally don't have much of it to spare. If you have a physical server with a spare USB port, and a demonstrable need for high-grade entropy, you could do worse than get yourself an Entropy Key. I don't normally recommend specific products on SF, but I rather like this one, and it does the job nicely.

Here's the depth of my pool before fitting the key:

and here's the pool after:

Declaration of interest: I have no connection with the makers except that I bought one of their products, at full price, and like it.

Edit (July 2015): the Entropy Key website has for some time said that they're out of stock, and they don't know when they'll have more made. However, OneRNG, a project to make a completely-open, verifiable, USB-connected entropy generator, was fully funded on kickstarter, and at the time of writing intends to start selling them via a webstore once their kickstarter obligations are fulfilled.