The Network Menu

The network menu can be used to tweak the networking configuration by adding specific hosts and routes, or configuring the uplink and adding VLANs. This menu should not be confused with the Network configuration wizard available at Menubar ‣ System ‣ Network Configuration, that allows to configure interfaces, zones, and to define uplinks, although many settings and configuration options, especially in the Interfaces menu item are the same found there.

The sub-menu on the left-hand side of the screen contains these items, each of which groups several configuration options:

• Edit hosts - define hosts for local domain name resolution
• Routing - set up static routes and policy routing
• Interfaces - edit the uplinks or create VLANs
• Wireless - set up wireless network connections

New in version 2.5: the wireless module

Edit hosts

The page contains the list of hosts previously defined. Each line contains an IP address, the associated hostname, and the domain name, if specified. Two available actions are available for each entry: To edit it or to delete it.

Warning

Deleting an host entry by clicking on the small icon does not require any confirmation and is not reversible. If deleted by mistake, an entry must be re-added manually.

A new entry in the file can be added by clicking on the Add a host link right above the table. A simple form will replace the table, in which to enter the following options:

IP address

The IP address of the remote host.

Hostname

The hostname associated to the IP address.

Domain name

An optional domain name.

Note

Unlike in the /etc/hosts file (see below), each IP address added here corresponds to one hostname and viceversa. To add two hostnames to a same IP, add two entries with the same IP address.

The choice can be confirmed by clicking on the Add Host button. To associate more hostnames to the same IP address, repeat the procedure by inserting the same IP address but a different name.

Hosts management, dnsmasq and /etc/hosts.

The dnsmasq application is used in small networks as DNS server for local hosts and as a DNS forwarder and caching server for worldwide DNS servers. The Endian UTM Appliance uses dnsmasq to be able to correctly resolve and answer DNS requests coming from the GREEN, ORANGE, and BLUE zones. It is sometimes desirable (e.g., for testing purposes on a remote website) to override some entries in dnsmasq, or to add some local server to dnsmasq’s cache, for local clients to be able to connect to it.

The hosts added in this page are stored in a dnsmasq’s settings file and merged with the /etc/hosts file at every restart of the daemon. Host added to that files directly via CLI will not persist after a reboot of the Endian UTM Appliance or a restart of dnsmasq.

The /etc/hosts file contains the so-called static lookup table, in the form:

IP1  hostname1  [hostname2]
IP2  hostname3  [hostname4] [hostname5]

Here, IP1 and IP2 are unique (numerical) IP addresses and hostname1, hostname2, hostname3,`hostname4`, and hostname5 are custom names given to those IPs. Names within square brackets are optional: In other words, each IP address can be associated with one or more names of known hosts. Custom host entries can be added to the file, that will then be resolved for all the clients connecting through the Endian UTM Appliance. On a typical Endian UTM Appliance, the /etc/hosts file contains at least the following entries:

127.0.0.1     localhost.localhost localhost
172.20.0.21   myappliance.localdomain myappliance
172.20.0.21   spam.spam spam
172.20.0.21   ham.ham      ham
172.20.0.21   wpad.localdomain wpad

Here, 127.0.0.1 is the IP address of the loopback device, localhost, which is a mandatory entry for the correct workink of any Linux system; while 172.20.0.21 is the IP address of the GREEN interface. The entries listed for that IP have the following meaning and purposes:

myappliance.localdomain

The hostname and domainname of the Endian UTM Appliance, as set up during the Network configuration .

spam.spam spam and ham.ham ham

These two entries combined are used for the training of the spamassassin e-mail filter.

wpad.localdomain wpad

A facility for some browsers to detect and apply proxy settings automatically without the user’s interaction when the prosy is not transparent.

Routing

Besides the default routing table, that can be seen in Menubar ‣ Status ‣ Network status, the routing on the Endian UTM Appliance can be improved with static and policy routing rules. This page displays a unique table that contains all the custom routings, although new rules are added from the two different tabs that present on this page. Indeed, static and policy routing rules require slight different settings. The table contains a summary of the rule: the source and destination networks or zones, the gateway, a remark, and the list of available actions: Enable or disable, edit, and delete a rule.

Whenever a modification is carried out on the routing table, it is required that the changes be saved and the service be restarted.

Static routing

A static route allows to associate specific source and destination networks with a given gateway or uplink. A click on the Add a new route link above the table allows create new routes by defining the following fields in the form that will appear:

Source Network

The source network, in CIDR notation.

Destination Network

The destination network, in CIDR notation.

Route Via

Four options are available to define through which means should the traffic be channeled: Static Gateway, Uplink, OpenVPN User, or L2TP User. In the case the Static Gateway is selected, the IP address of a gateway should be provided in the text box on the right. Otherwise, a drop-down will appear, proposing the choice among the available uplinks, OpenVPN users, or L2TP users.

New in version 2.5: Routing via OpenVPN and L2TP Users.

Enabled

A ticked checkbox means that the rule is enabled (default). If unchecked, then the rule is only created but not activated: It can always be enabled later.

Remark

A remark or comment to explain the purpose of this rule.

See also

A guide to set up basic static routes.

Policy routing

A policy route rule allows to associate specific network addresses, zones, or services (expressed as port and protocol) with a given uplinks.

Policy routing, HTTP proxy, and uplink.

The interaction between these three components of the Endian UTM Appliance might produce some behaviour that may appear strange or even wrong when clients in the zones try to access the Internet. There are indeed three steps to highlight, for a correct understanding how traffic flows to the Internet when both HTTP proxy is enabled and there are policy routing rules defined:

1. An HTTP proxy uses the main uplink (i.e., it accesses the RED zone and the Internet using the main uplink).
2. An HTTP proxy “breaks” a connection from a client to a remote server in two connections: One from the client to the Endian UTM Appliance and one from the Endian UTM Appliance to the remote server.
3. Policy routing rules are taken into account after the traffic goes through the HTTP proxy.

When clicking on the Create a policy routing rule link, a form will open, which seems rather more complicated then the one for static routes and very similar to the firewall rule’s editor. However, this policy rule editor is much like the previous one, but gives more control over the definition of the rule. Additionally, the setup of the rule is guided by several drop-down menus, to simplify entering the data in the following fields:

Source

The first drop-down menu allows to choose the source of the traffic. More entries, one per line, are accepted, but all must belong to the same type, either: A zone or interface, OpenVPN or L2TP users, IPs or networks, or MAC addresses. Depending on the choice, different values shall be supplied. To apply the rule to all sources, select <ANY>.

Destination

The second drop-down menu permits the choice of the destination of the traffic, in form of a list of IPs, networks, OpenVPN or L2TP users. Again, by selecting <ANY> the rule will match every destination.

Service/Port

The next two drop-down menus allow to specify the service, protocol, and a destination port for the rule when the TCP, UDP, or TCP + UDP protocols are selected. Some predefined combinations service/protocol/port exists, like HTTP/TCP/80, <ALL>/TCP+UDP/0:65535, or <ANY>, which is a shortcut for all services, protocols, and ports. User defined permits to specify a custom protocol and the ports to block, an option that proves useful when running services on ports different from the standard ones.

Protocol

The type of traffic that is interested by the rule: TCP, UDP, TCP+UDP, ESP, GRE, and ICMP. TCP and UDP are the most used, GRE is used by tunnels, ESP by IPsec, and ICMP by the ping and traceroute commands.

Route Via

How the traffic should be routed for this rule. Four options are available:

Static gateway: In this case an IP Address shall be provided

Uplink: The uplink that should be used for this rule. There is the option, when the uplink becomes unavailable, that the routing be carried over to the backup link corresponding to the selected uplink. This option is enabled when the checkbox next to the drop-down menu is ticked.

OpenVPN user: An OpenVPN user, choosen from those available in the drop-down menu.

L2TP user: An L2TP user, choosen from those available in the drop-down menu.

Type Of Service

The type of service (TOS) can be chosen here. See below for more about this topic.

Remark

A remark or comment to explain the purpose of this rule.

Position

The position in which to insert the rule (relative position in the list of rules).

Enabled

Tick this checkbox to enable the rule (default). If unchecked, the rule is created but not active: A rule can be enabled later.

Log all accepted packets

This checkbox must be ticked to log all the packets affected by this rule.

Warning

the activation of this option may cause the size of the log files to dramatically improve.

TOS (Type of Service) and DSCP (Differentiated Services Code Point).

The TOS is an eight bit log field of the IP header of an IPv4 packet, initially intended to provide a means for the servers to manage that packet along its path to the destination. It was originally defined in RFC 791 and RFC 1349.

The binary number behind each type of service describes how this type works. The first three bits describe the precedence of the packet (000 default precedence, 111 highest precedence), the fourth bit describes the delay (0 means normal delay, 1 low delay), the fifth bit describes the throughput (1 increases throughput, 0 normal throughput), the sixth bit controls the reliability (1 increases reliability, 0 normal reliability). The last 2 bits are unused.

Due to its scarce use, the eight-bit field used for TOS was reused for DSCP, the evolution of TOS which represents a means to define Quality of Service on network traffic.

In the Endian UTM Appliance, the values for the TOS can be selected among the following, which are actually DSCP:

• Eight IP precedence values for Class Selectors (CS0-7), which denote backward compatibility with the TOS field. In other words, these are ‘true’ TOS values.
• Twelve values for Assured Forwarding (AF*xy*, x being a class from 1 to 4 and y being a ‘drop precedence’ from 1 to 3 -low, medium, high) that provide low packet loss with minimum guarantees about latency. AFs are defined in RFC 2597 and RFC 3260.
• One value for Expedited Forwarding (EF PHB), defined in RFC 3246 and used to give the highest priority to packets. It is useful for services requiring low delay, low latency, and low rate of losses, like e.g., VoIP or video streaming.

Those types of value, however, have been replaced in recent appliances with the following, easier to read:

See also

There is a tutorial to set up basic policy routes available here.

Interfaces

The uplinks manager allows to carry out a number of tasks that are related with the uplink and the interfaces, and in particular to define custom VLANs on the network interfaces.

Uplink editor

By default, the uplink editor shows the available uplinks that have been created. Additional uplinks are defined by clicking on the Create an uplink hyperlink above the list of uplinks. A rather long page, full of configurable options will open, that should be filled with appropriate values very similar to those in the network configuration wizard. Depending on the type of uplink chosen, the available settings will differ.

Note

Not all the available options are described here: They are the same that are present in the network configuration and depend on the type of the uplink chosen, so please refer to that section (see link below) for the full explanation of each option.

Type

The selection of the type of RED connection includes one additional protocol, compared to those available in the network configuration wizard: PPTP. PPTP can be configured to work in static or in DHCP mode, selectable from the respective value from the “PPTP method” drop-down. The IP address and netmask must be defined in the appropriate textfields if the static method has been chosen, in which case additional IP/netmask or IP/CIDR combinations can be added in the field below if the checkbox is ticked. Phone number, username, and password are not required but may be needed for some configurations to work, depending on the provider’s settings. The authentication method can be either PAP or CHAP: if unsure, keep the default value “PAP or CHAP”.

Uplink is enabled

Tick this checkbox to enable the uplink.

Start uplink on boot

This checkbox specifies whether an uplink should be enabled at boot time or not. This option proves useful for backup uplinks which are managed but do not need to be started during the boot procedure.

Uplink is managed

Tick this checkbox for the uplink to be managed. See the Uplink Information Plugin under Menubar ‣ System ‣ Dashboard for a discussion about managed and manual modes.

if this uplink fails activate

If enabled, an alternative connection can be chosen from a drop-down menu, which will be activated when this uplink fails.

Check if these hosts are reachable

Tick this option to enter a list of IP or hostnames that will be ping-ed when the uplink fails, to check whether it has reconnected.

Hint

One of those hosts could be the provider’s DNS server or gateway.

In the advanced settings panel, two other options can be customised:

Reconnection timeout

The time interval (in seconds) after which an uplink tries to reconnect if it fails. This value depends on the provider’s settings. If unsure, leave this field empty.

MTU

A custom value for the MTU size. See here for a discussion about the reasons to modify the default value.

See also

Network configuration , steps 1, 4, and 5.

Menubar ‣ System ‣ Network Configuration

A tutorial that explains the setup of a failover uplink.

VLANs

The idea behind offering VLAN support in Endian UTM Appliance is to allow arbitrary associations of VLAN IDs to the zones and to provide an additional level of separation (and therefore adding another level of security) between the zones. The existing VLANS are shown in the table, if any had already been created.

A new VLAN can be defined by clicking on the Add new VLAN hyperlink above the VLAN list. In the form that will open a few click suffice to create an association between an interface and a VLAN, by specifying a few values:

Interface

The physical interface to which the VLAN is connected to. Only the available interfaces can be chosen from the drop-down menu. The menu also shows the status of the link of the interface.

VLAN ID

The VLAN ID, which must be an integer number between 0 and 4095.

Zone

The zone to which the VLAN is associated with. Only the zones that have been defined in the network configuration wizard can be selected. The option “NONE” can be chosen, if that interface is used as a High Availability management port.

Warning

It is not possible to define a VLAN that serves one zone (e.g., a VLAN on BLUE) on an interface that already serves another zone (e.g., eth1 serving GREEN). When trying to do so, the form closes and a red callout appears, informing that the VLAN can not be created.

Whenever a virtual LAN is created, a new interface is created and named as ethX.y where X is the number of the interface and y is the VLAN ID. This interface is then assigned to the chosen zone and will show up as a regular interface in the various sections that report network information, like Menubar ‣ Status ‣ Network Configuration or in the Dashboard, where it can be selected to be drawn in the graph.

Wireless

New in version 2.5: WiFi capabilities

The wireless module presents some options to configure the Endian UTM Appliance as an access point. If not enabled, only the switch to activate wireless support is shown in the page. Upon activation, a box appears, divided in two parts by the Add new SSID link. In the upper part appears a panel carrying the overall configuration options, while in the lower part there is the list of the available SSIDs, right below a navigation and search bar and above a set of buttons to carry out an action on more SSIDs at once. The following options are available to configure the wireless module:

Country

The Country in which the Endian UTM Appliance operates, chosen from a drop-down menu. It is used to tailor the availability of the channels.

Channel

The channel(s) on which the wireless should broadcast the Wireless signal. The channels available for wireless depend on the national regulations on the telecommunications.

Wireless Mode

The mode used by the wireless, in terms of 802.11 standards (b, g, or n).

The list of the SSIDs, which is initially empty, presents the following information: The SSID name, the zone, the encryption, and a remark, which are described below.

To add a new SSID, click on the Add new SSID to open the editor, in which to supply the following information:

SSID

The name of the SSID as it will be seen by local clients.

Broadcast SSID

The SSID is broadcast by default (i.e., the checkbox is ticked) meaning that clients will see it when active. If the SSID is not broadcast, it is hidden from the client’s view and to access it, it will be necessary for the client to provide the SSID’s name.

Zone

The zone to which the clients will belong, chosen from the drop-down menu among the available ones.

Encryption

The type of encryption to be used for the wireless connection. The options are: no encryption, WPA, Personal WPA2 or Enterprise WPA2.

Enabled

Tick this checkbox to enable the SSID.

Remark

A custom comment on this connection.