I have two leased centos servers, one to run mysql for backends to the web and mail server on the other, as well as data from my android apps. I am only planning to give access to the data server if you're coming through my apps or front-end server (api or no). Can I count on encryption keys for this?
I'm not planning on giving anyone else shell accounts at this time, only mail provided by cyrus-imapd as described here. I will be logging on via certificate only. I plan on developing a secure content provider that establishes a ssh tunnel to modify my data from my android apps.
What kind of attacks can I still expect? Please tell me this won't happen to me, or a repeat of the time my server was hijacked and became the sender of a billion spam mails. I've jettisoned commercial cms and panels, but my provider does use parallels. Oh and I'll be using tripwires on both systems (bonuses for good tripwire recommendations.)