Openvpn warning messages question

I have reverted to version 18.9 with a new installation. I then installed ipvanish using the Zomboided vpn manager because there is no dedicated vpn manager from ipvanish as far as I can see.
The installation went OK but I noticed some warning massages during the setup:-

WARNING - keysize is DEPRECATED and will be removed in OpenVPN 2.6.
What sized key should I be using I ask?

WARNING This configuration may cache passwords in memory - use the auth-nocache option.

Can anybody shine any light on the keysizee warning?
I would be happy to add the auth-nocache option if I knew where to put it. Can you help please?

Hi,

Depends, what key size are using, what key sizes do ipvarnish offer? If ipvarnish is anything like privateinternetacess the options are probably 128bit or 256bit. 256 is more secure, but has more overheads, so download speed will be reduced. Switching to this will probably clear the error, but its probably safe to ignore. It would take a very long and a lot of resources to time decrypt a 128bit key.
@Budgie
Ignore me, I’ve just found this:

keysize

I was on the wrong track, anyway its safe to ignore; as openvpn will anyway.

Again I tend to ignore this, but you can add auth-nocache to the vpn conf file or ovpn; if you want.

Thanks Tom.