I have been building several 4451 routers and 4507R+E switches recently. Right after the devices boot I run a script to create the configuration. The devices have only been up for a couple minutes when the "crypto key generate rsa mod 2048" command is run.
Below is the output. The routers have consistently been zero and switches under 4 seconds.
How can a newly booted device have enough entropy to create a 2048 bit RSA key pair in zero or 3 seconds?
Thanks in advance for any information!
TestLab_4451(config)#crypto key generate rsa mod 2048
The name for the keys will be: TestLab_4451.pu.pri
% The key modulus size is 2048 bits
% Generating 2048 bit RSA keys, keys will be non-exportable...
[OK] (elapsed time was 0 seconds)
4507R+E
TestLab_4507_01(config)#crypto key generate rsa mod 2048
The name for the keys will be: TestLab_4507_01.pu.pri
% The key modulus size is 2048 bits
% Generating 2048 bit RSA keys, keys will be non-exportable...
[OK] (elapsed time was 3 seconds)