So far I have used the VirtualBox console to connect to my virtual machine running Linux (CentOS 7). This is fine and good for one session, but if you want to run multiple terminals you have to install a Telnet/SSH client.
I will be using a client called “Putty” which is free and very widely used. Download Putty.exe to your desktop.
Now we have Putty now but it’s useless until we make some changes on our local virtual machine. (If you’ve installed Linux on a real physical machine or had Linux installed on a server VM then this next steps might not apply)
We need to know which IP address our Linux server is running on. In your VM console run “#ifconfig”. This is very similar to running ipconfig on Windows command line. My results are below.
Note, the IP address of the virtual machine is 10.0.2.15. Now that we know that we go to VirtualBox, select the VM in question and click on Settings and then select “Network”.
Expand the “Advanced” tab if it is not already showing and click on “Port Forwarding”.
Here, click the +Plus sign and add a new rule. It can be called whatever, I called mine SSH. Add the line as shown. If you have a different VM IP than 10.0.2.15 then you will want to use that.
At this point you can run that Putty.exe that you downloaded earlier. Enter 127.0.0.1 as your IP address and click “Open”.
At this point you should get a “login as:” prompt. Enter your username and password and you should be connected.
Now you can open up multiple terminal windows and run multiple programs at once.
If your terminal keeps timing out too early for you, you can change it so that it “stays alive” for a much longer time by doing something like this.
Open the sshd_config file.
# nano /etc/ssh/sshd_config
Add/change the following lines
ClientAliveInterval 30 TCPKeepAlive yes ClientAliveCountMax 99999
3/2/2015 Edit: Despite my changes, my terminal sessions were still getting disconnected. For me the problem was with VirtualBox. I had to download the beta version (4.3.23 r98674). Then I could not launch any VMs because I would get a STATUS_OBJECT_NAME_NOT_FOUND error having to do with \Device\VBoxDrvStub. I then uninstalled Windows Update KB3004394 and then reinstalled VirtualBox. Now things seem better. Hope that anybody having this problem finds this update helpful.