Memory Required for SSH-only Linux Setup

I am attempting to set up a minimal SSH-only installation of Debian or CentOS on a virtual machine for SSH access into an internal network.

The purpose of the setup will be to allow SSH access into the rest of the internal network—that's it. It will not need to serve any other function and will have very few additional utilities installed.

For clarity, here is the primary usage scenario for the installation:

1. SSH into the machine from outside of the network.


2. SSH out from this machine to another machine on the internal network

My questions are:

• What is the minimum amount of memory required for such a setup without running into stability or performance issues?


• How much additional memory should be reserved to secure the system if it is later decided to harden up with AppArmor or other hardening agents?


• Is there an alternative distro (Linux or BSD) that would be better suited for this kind of application?

Additional Considerations:

• The machine must run with minimal resources ( < 128 MiB RAM )


• sshuttle may be used frequently to access the machine


• The ssh server and client will be OpenSSH

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Note: A more distro-oriented version of this question was posted here: Lightweight SSH-only distro (< 128 MiB RAM)

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