Category Archives: FortiOS 5.4 Handbook

The complete handbook for FortiOS 5.4

Interfaces

Interfaces

When setting up an address one of the parameters that is asked for is the interface. This means that the system will expect to see that address only on the interface that you select. You can only select one interface. If you expect that the address may be seen at more than one interface you can choose the “any” interface option. Whenever, possible it is best to choose a more specific interface than the “any” option because in the GUI configuration of firewall policies there is a drop down field that will show the possible addresses that can be used. The drop down will only show those addresses that can be on the interface assigned for that interface in the policy.

 

Example:

  • You have an address called “XYZ”.
  • “XYZ” is set to the WAN1 interface because that is the only interface that will be able to access that address.
  • When you are selecting a Source Address in the Web-based Manager for a policy that is using the DMZ the address “XYZ” will not be in the drop-down menu.

 

When there are only 10 or 20 addresses this is not a concern, but if there are a few hundred addresses configured it can make your life easier.

Addresses, address groups, and virtual IPs must have unique names to avoid confusion in firewall policies. If an address is selected in a policy, the address cannot be deleted until it is deselected from the policy.

Addressing Best Practices Tip

The other reason to assign a specific interface to addresses is that it will prevent you from accidentally assigning an address where it will not work properly. Using the example from earlier, if the “XYZ” address was assigned to the “Any” interface instead of WAN1 and you configure the “XYZ” address.

Addressing Best Practices Tip

Don’t specify an interface for VIP objects or other address objects that may need to be moved or approached from a different direction. When configuring a VIP you may think that it will only be associated with a single interface, but you may later find that you need to reference it on another interface.

Example: Some web applications require the use of a FQDN rather than an IP address. If you have a VIP set up that works from the Internet to the Internal LAN you wont be able to use that VIP object to access it from an internal LAN interface.

 

Addresses

Addresses

Firewall addresses define sources and destinations of network traffic and are used when creating policies. When properly set up these firewall objects can be used with great flexibility to make the configuration of firewall policies simpler and more intuitive. The FortiGate unit compares the IP addresses contained in packet headers with a security policy’s source and destination addresses to determine if the security policy matches the traffic.

The address categories and the types within those categories on the FortiGate unit can include:

  • IPv4 addresses
  • IP address and Netmask
  • IP address range
  • Geography based address
  • Fully Qualified Domain Name (FQDN) address
  • Wildcard FQDN
  • IPv4 Address Group
  • IPv6 addresses
  • Subnets
  • IP range
  • IPv6 Address Group
  • Multicast addresses
  • Multicast IP range
  • Broadcast subnets
  • Explicit Proxy Addresse
  • URL Pattern
  • Host Regex Match
  • URL Category
  • HttpMethod
  • User Agent
  • HTTP Header
  • Advanced (Source)
  • Advanced (Destination)
  • IP Pools (IPv4)
  • Overload
  • One-to-one
  • Fixed Port Range
  • Port Block Allocation
  • IP Pools (IPv6)
  • Virtual IP Addresses
  • IPv4
  • IPv6
  • NAT46
  • NAT64

UUID Support

UUID Support

A Universally Unique Identified (UUID) attribute has been added to some firewall objects, so that the logs can record these UUID to be used by a FortiManager or FortiAnalyzer unit. The objects currently include:

  • Addresses, both IPv4 and IPv6
  • Address Groups, both IPv4 and IPv6
  • Virtual IPs, both IPv4 and IPv6
  • Virtual IP groups, both IPv4 and IPv6
  • Policies, IPv4,IPv6 and IP64

A UUID is a 16-octet (128-bit) number that is represented by 32 lowercase hexidecimal digits. The digits are displayed in five groups separated by hyphens (-). The pattern is 8-4-4-4-12; 36 digits if you include the hyphens.

Note: UUID is only supported on large-partition platforms (>=128M)

 

Firewall objects

Firewall objects

As was mentioned earlier, the components of the FortiGate firewall go together like interlocking building blocks. The Firewall objects are a prime example of those building blocks. They are something that can be configured once and then used over and over again to build what you need. They can assist in making the administration of the FortiGate unit easier and more intuitive as well as easier to change. By configuring these objects with their future use in mind as well as building in accurate descriptions the firewall will become almost self documenting. That way, months later when a situation changes, you can take a look at a policy that needs to change and use a different firewall object to adapt to the new situation rather than build everything new from the ground up to accommodate the change.

 

This chapter includes information about the following Firewall objects:

  • Addresses
  • Services and TCP ports
  • Firewall schedules
  • Security profiles

 

Policy Monitor

Policy Monitor

Once policies have been configured and enabled it is useful to be able to monitor them. To get an overview about what sort of traffic the policies are processing go to Policy > Monitor > Policy Monitor.

The window is separated into two panes.

 

Upper Pane

The upper pane displays a horizontal bar graph comparing the Top Policy Usage based on one of the following criteria:

  • Active Sessions
  • Bytes
  • Packets

The criteria that the displayed graph is based on can be selected from the drop down menu in the upper right corner of the pane. The field name is Report By:.

The bars of the graph are interactive to an extent and can be used to drill down for more specific information. If you hover the cursor over the bar of the graph a small popup box will appear displaying more detailed information. If the bar of the graph is selected an entirely new window will be displayed using a vertical bar graph to divide the data that made up the first graph by IP address.

For example if the first graph was reporting usage by active sessions it would include a bar for each of the top policies with a number at the end showing how many sessions were currently going through that policy. If one of the bars of the graph was then selected the new bar graph would show the traffic of that policy separated by either Source Address, Destination Address or Destination Port. As in the other window, the selection for the reported criteria is in the upper right corner of the pane. If the parameter was by source address there would be a bar for each of the IP addresses sending a session through the policy and the end of the bar would show how many sessions.

To go back to the previous window of information in the graphs select the Return link in the upper left of the pane.

 

Lower Pane

The lower pane contains a spreadsheet of the information that the bar graph will derive their information from. The column headings will include:

  • Policy ID
  • Source Interface/Zone
  • Destination Interface/Zone
  • Action
  • Active Sessions
  • Bytes
  • Packets

 

Quality of Service

Quality of Service

The Quality of Service (QoS) feature allows the management of the level of service and preference given to the various types and sources of traffic going through the firewall so that the traffic that is important to the services and functions connecting through the firewall gets the treatment required to ensure the level of quality that is required.

QoS uses the following techniques:

Traffic policing        Packets are dropped that do not conform to bandwidth limitations

Traffic Shaping

Assigning minimum levels of bandwidth to be allocated to specific traffic flows to guar- antee levels of servers or assigning maximum levels of bandwidth to be allocated to specific traffic flows so that they do not impede other flows of traffic.

This helps to ensure that the traffic may consume bandwidth at least at the guaranteed rate by assigning a greater priority queue if the guarantee is not being met. Traffic shaping also ensures that the traffic cannot consume bandwidth greater than the maximum at any given instant in time. Flows that are greater than the maximum rate are subject to traffic policing.

Queuing

Assigning differing levels priority to different traffic flows so that traffic flows that are adversely effected by latency are prevented from being effected by traffic flows that are not subject to the effects of latency. All traffic in a higher priority traffic queue must be completely transmitted before traffic in lower priority queues will be transmitted.

An example of where you would want to use something like this is if you had competing traffic flows of Voice over IP traffic and email traffic. The VoIP traffic is highly susceptible to latency issues.If you have a delay of a few seconds it is quickly noticeable when it is occurring. Email on the other hand can have a time delay of much longer and it is highly unlikely that it will be noticed at all.

By default, the priority given to any traffic is high, so if you want to give one type of traffic priority over all other traffic you will need to lower the priority of all of the other traffic.

 

Traffic Logging

Traffic Logging

When you enable logging on a security policy, the FortiGate unit records the scanning process activity that occurs, as well as whether the FortiGate unit allowed or denied the traffic according to the rules stated in the security policy. This information can provide insight into whether a security policy is working properly, as well as if there needs to be any modifications to the security policy, such as adding traffic shaping for better traffic performance.

Depending on what the FortiGate unit has in the way of resourses, there may be advantages in optimizing the amount of logging taking places. This is why in each policy you are given 3 options for the logging:

  • No Log – Does not record any log messages about traffic accepted by this policy.
  • Log Security Events – records only log messages relating to security events caused by traffic accepted by this policy.
  • Log all Sessions – records all log messages relating to all of the traffic accepted by this policy.

 

Depending on the the model, if the Log all Sessions option is selected there may be 2 additional options. These options are normally available in the GUI on the higher end models such as the FortiGate 600C or larger.

  • Generate Logs when Session Starts
  • Capture Packets

You can also use the CLI to enter the following command to write a log message when a session starts:

config firewall policy edit <policy-index>

set logtraffic-start end

Traffic is logged in the traffic log file and provides detailed information that you may not think you need, but do. For example, the traffic log can have information about an application used (web: HTTP.Image), and whether or not the packet was SNAT or DNAT translated. The following is an example of a traffic log message.

2011-04-13

05:23:47 log_id=4 type=traffic subtype=other pri=notice vd=root status=”start”

src=”10.41.101.20″ srcname=”10.41.101.20″ src_port=58115 dst=”172.20.120.100″ dstname=”172.20.120.100″ dst_country=”N/A” dst_port=137 tran_ip=”N/A”

tran_port=0 tran_sip=”10.31.101.41″ tran_sport=58115 service=”137/udp” proto=17

app_type=”N/A” duration=0 rule=1 policyid=1

 

 

 

 

sent=0 rcvd=0 shaper_drop_sent=0 shaper_drop_rcvd=0 perip_drop=0 src_int=”internal” dst_int=”wan1″ SN=97404 app=”N/A” app_cat=”N/A” carrier_ep=”N/A”

If you want to know more about logging, see the Logging and Reporting chapter in the FortiOS Handbook. If you want to know more about traffic log messages, see the FortiGate Log Message Reference.

Endpoint Security

Endpoint Security

Endpoint security enforces the use of the FortiClient End Point Security (FortiClient and FortiClient Lite) application on your network. It can also allow or deny endpoints access to the network based on the application installed on them.

By applying endpoint security to a security policy, you can enforce this type of security on your network. FortiClient enforcement can check that the endpoint is running the most recent version of the FortiClient application, that the antivirus signatures are up-to-date, and that the firewall is enabled. An endpoint is usually often a single PC with a single IP address being used to access network services through a FortiGate unit.

With endpoint security enabled on a policy, traffic that attempts to pass through, the FortiGate unit runs compliance checks on the originating host on the source interface. Non-compliant endpoints are blocked. If someone is browsing the web, the endpoints are redirected to a web portal which explains the non-compliance and provides a link to download the FortiClient application installer. The web portal is already installed on the FortiGate unit, as a replacement message, which you can modify if required.

Endpoint Security requires that all hosts using the security policy have the FortiClient Endpoint Security agent installed. Currently, FortiClient Endpoint Security is available for Microsoft Windows 2000 and later only.

For more information about endpoint security, see the Security Profiles chapter in the FortiOS Handbook.