Nomadix Universal subscriber gateway User Manual page 214

Because there is a parameter buffer size limitation of the "openssl" command, the
argument length should not have more than 80 characters.
If you are creating multiple keys, please output them into different directories and
save them as different names. However, if you saving them as a different namse, you
must change the names back to "cakey.pem" when trying to FTP to the USG.
"
Do not include "-des3" option to keep the private key in an unencrypted
form.
Here is the output of cakey.pem:
210
U S
NIVERSAL UBSCRIBER
Quick Reference Guide
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ATEWAY