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crypto key generate ssh

Stuart Teo
Trusted Contributor

crypto key generate ssh

In a 5300xl running E.07.37, I noticed a behavior when I issue the "crypto key generate ssh" command.

On some switches, the key was generated real quick. In some switches, it would take up to 1 minute.

What exactly is the key/entropy cache in the message "Installing new RSA key. If the key/entropy cache is depleted, this could take up to a minute."
If a problem can be fixed, there's nothing to worry. If a problem can't be fixed, worrying ain't gonna help. Bottom line: don't worry.
2 REPLIES
Jerome Henry
Honored Contributor

Re: crypto key generate ssh

Entropy usually refers to a colletion of random values. When key/entropy file is full, then the system uses these random values to calculate a hard to guess key.
If this file is depleted, then the system doesn't have random values, and has to calculate many random numbers in order to make a solid key. This process (calculating values you can't take from elsewhere) takes time, that's why it turns to a minute or so in this case.

hth

J
You can lean only on what resists you...
Stuart Teo
Trusted Contributor

Re: crypto key generate ssh

Thanks for your response! Let me rephrase my question. Under what condition would the key/entropy cache is depleted?
If a problem can be fixed, there's nothing to worry. If a problem can't be fixed, worrying ain't gonna help. Bottom line: don't worry.