Generate a Key & Certificate using tmsh

# tmsh create sys crypto key <key_name> gen-certificate common-name
<cert_name> security-type nethsm
For Example
# tmsh create sys crypto key f5-testkey gen-certificate common-name
utimaco.bigip.com security-type nethsm

# tmsh list sys crypto key f5-testkey
sys crypto key default.key {
key-size 2048
key-type rsa-private
security-type normal
}
sys crypto key f5_api_com.key {
key-size 4096
key-type rsa-private
security-type password
}
sys crypto key f5-testkey {
key-id s7cb7a32bd11d323gad1dc23fhd9a1a8
key-size 2048
key-type rsa-private
nethsm-partition auto
security-type nethsm
}

# tmsh save sys config