What is best secure and anonymous OS for hosting Tor or I2P service ?
i want server OS full support php and mysql
I am confused in choosing ٍServer OS (Debian - Ubuntu - Centos - Redhat)
I'm trying to suggest OpenBSD.
You may read the FAQ, it is great documentation.
Great security mechanisms shall give you kind of protection.
What to say about anonymity. If you would stay as a node of network, you will be listed everywhere, e.g. here http://torstatus.blutmagie.de
But if you are interesting in the hidden service of Tor, you need no to stay like a node of network. Here you are probably can achieve kind of anonymity of your OS.
Say, you could cut of every banners, every labels. Client of your hidden service will not be able to recognize what kind of OS you are using, Windows or Unix-like.
You may setup your hidden service of Tor inside the Virtual Machine based on liveCD of OpenBSD with securitylevel=2.
However, as you mention you want to launch I2P relay. OpenBSD only for the last year has Java support. Here might be bugs.
You must make it anonymous, it is not anonymous by default. It means you must pay administrator to do it for you. ubuntu is snitching users, there was info about it. I would choose debian + whonix or configure some virtual machine similar to whonix. in that way if somebody makes attack, he will attack virtual machine and not debian (host machine). if you want to pay I can do it for you. I don't know if such offer is allowed here (berkman(at)vfemail.net).