System information

147Chapter 9 Customizing Services
If you want to allow access to VPN service outside your local network and your
local network has a separate rewall device, ask the rewall administrator to open
the rewall for the ports and protocols that VPN service uses. For a list of ports,
see “Services and Ports” on page 175.
Changing the VPN Shared Secret
You can use Server Preferences to change the shared secret that the server and a client
computer use for authentication when making a VPN connection. Periodically changing
the shared secret improves VPN security, but is inconvenient because users must also
change the shared secret on computers they use for VPN connections.
To change the VPN shared secret:
1 In the VPN pane of Server Preferences, click Edit.
2 Select “Show shared secret” so you can read the secret, and then enter a new secret
and click OK.
The shared secret should be at least 8 characters (preferably 12 or more) including
letters, digits, and symbols, but without spaces. Initially, the shared secret is 32 random
characters.
You can use Password Assistant to help you compose a new shared secret. Temporarily
switch to the Users pane, click Account, click Reset Password, click the Key button to
the right of the New Password eld, and then click Cancel and return to the VPN pane.
Password Assistant remains open, and you can use it to generate a new shared secret
that you copy from the Suggestion eld and paste into the Shared Secret eld.