User guide

Basic Firewall Configuration
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2.5.2.3. Trusted Services
Enabling options in the Trusted services list allows the specified service to pass through the firewall.
WWW (HTTP)
The HTTP protocol is used by Apache (and by other Web servers) to serve web pages. If you plan
on making your Web server publicly available, select this check box. This option is not required for
viewing pages locally or for developing web pages. This service requires that the httpd package
be installed.
Enabling WWW (HTTP) will not open a port for HTTPS, the SSL version of HTTP. If this service is
required, select the Secure WWW (HTTPS) check box.
FTP
The FTP protocol is used to transfer files between machines on a network. If you plan on making
your FTP server publicly available, select this check box. This service requires that the vsftpd
package be installed.
SSH
Secure Shell (SSH) is a suite of tools for logging into and executing commands on a remote
machine. To allow remote access to the machine via ssh, select this check box. This service
requires that the openssh-server package be installed.
Telnet
Telnet is a protocol for logging into remote machines. Telnet communications are unencrypted and
provide no security from network snooping. Allowing incoming Telnet access is not recommended.
To allow remote access to the machine via telnet, select this check box. This service requires that
the telnet-server package be installed.
Mail (SMTP)
SMTP is a protocol that allows remote hosts to connect directly to your machine to deliver mail.
You do not need to enable this service if you collect your mail from your ISP's server using POP3
or IMAP, or if you use a tool such as fetchmail. To allow delivery of mail to your machine, select
this check box. Note that an improperly configured SMTP server can allow remote machines to
use your server to send spam.
NFS4
The Network File System (NFS) is a file sharing protocol commonly used on *NIX systems.
Version 4 of this protocol is more secure than its predecessors. If you want to share files or
directories on your system with other network users, select this check box.
Samba
Samba is an implementation of Microsoft's proprietary SMB networking protocol. If you need to
share files, directories, or locally-connected printers with Microsoft Windows machines, select this
check box.
2.5.2.4. Other Ports
The Firewall Configuration Tool includes an Other ports section for specifying custom IP ports as
being trusted by iptables. For example, to allow IRC and Internet printing protocol (IPP) to pass
through the firewall, add the following to the Other ports section:
194:tcp,631:tcp