Confguring SSH Version 2

[johnlloyd_13]

hi,

i'll be configuring SSH version 2 and can see some of our ASA have existing RSA/general purpose keys (some ASA have several keys) with modulus 1024.

can i re-use the existing 1024 RSA key for SSH version 2?

or do i need to generate a new RSA key with 2048 modulus?

my worry is some are old 5510 and 5520 with limited 256MB or 512MB RAM and CPU is around 50-70%.

[Rahul Govindan]

If you already have a "Default-RSA-Key" with modulus 1024, you can re-use that without having to generate another key. For higher security, you can regenerate the same key as modulus 2048, but this may affect other certs which are using the existing key.

[johnlloyd_13]

hi,

will generating a new 2048 rsa key affect CPU performance?

some of our older ASA has more than 50% CPU.