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ReStructuredText
807 lines
28 KiB
ReStructuredText
.. _nat44:
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#####
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NAT44
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#####
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:abbr:`NAT (Network Address Translation)` is a common method of
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remapping one IP address space into another by modifying network address
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information in the IP header of packets while they are in transit across
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a traffic routing device. The technique was originally used as a
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shortcut to avoid the need to readdress every host when a network was
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moved. It has become a popular and essential tool in conserving global
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address space in the face of IPv4 address exhaustion. One
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Internet-routable IP address of a NAT gateway can be used for an entire
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private network.
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IP masquerading is a technique that hides an entire IP address space,
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usually consisting of private IP addresses, behind a single IP address
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in another, usually public address space. The hidden addresses are
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changed into a single (public) IP address as the source address of the
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outgoing IP packets so they appear as originating not from the hidden
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host but from the routing device itself. Because of the popularity of
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this technique to conserve IPv4 address space, the term NAT has become
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virtually synonymous with IP masquerading.
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As network address translation modifies the IP address information in
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packets, NAT implementations may vary in their specific behavior in
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various addressing cases and their effect on network traffic. The
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specifics of NAT behavior are not commonly documented by vendors of
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equipment containing NAT implementations.
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The computers on an internal network can use any of the addresses set
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aside by the :abbr:`IANA (Internet Assigned Numbers Authority)` for
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private addressing (see :rfc:`1918`). These reserved IP addresses are
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not in use on the Internet, so an external machine will not directly
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route to them. The following addresses are reserved for private use:
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* 10.0.0.0 to 10.255.255.255 (CIDR: 10.0.0.0/8)
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* 172.16.0.0 to 172.31.255.255 (CIDR: 172.16.0.0/12)
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* 192.168.0.0 to 192.168.255.255 (CIDR: 192.168.0.0/16)
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If an ISP deploys a :abbr:`CGN (Carrier-grade NAT)`, and uses
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:rfc:`1918` address space to number customer gateways, the risk of
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address collision, and therefore routing failures, arises when the
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customer network already uses an :rfc:`1918` address space.
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This prompted some ISPs to develop a policy within the :abbr:`ARIN
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(American Registry for Internet Numbers)` to allocate new private
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address space for CGNs, but ARIN deferred to the IETF before
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implementing the policy indicating that the matter was not a typical
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allocation issue but a reservation of addresses for technical purposes
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(per :rfc:`2860`).
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IETF published :rfc:`6598`, detailing a shared address space for use in
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ISP CGN deployments that can handle the same network prefixes occurring
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both on inbound and outbound interfaces. ARIN returned address space to
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the :abbr:`IANA (Internet Assigned Numbers Authority)` for this
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allocation.
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The allocated address block is 100.64.0.0/10.
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Devices evaluating whether an IPv4 address is public must be updated to
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recognize the new address space. Allocating more private IPv4 address
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space for NAT devices might prolong the transition to IPv6.
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Overview
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========
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Different NAT Types
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-------------------
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.. _source-nat:
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SNAT
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^^^^
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:abbr:`SNAT (Source Network Address Translation)` is the most common
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form of :abbr:`NAT (Network Address Translation)` and is typically
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referred to simply as NAT. To be more correct, what most people refer
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to as :abbr:`NAT (Network Address Translation)` is actually the process
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of :abbr:`PAT (Port Address Translation)`, or NAT overload. SNAT is
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typically used by internal users/private hosts to access the Internet
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- the source address is translated and thus kept private.
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.. _destination-nat:
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DNAT
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^^^^
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:abbr:`DNAT (Destination Network Address Translation)` changes the
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destination address of packets passing through the router, while
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:ref:`source-nat` changes the source address of packets. DNAT is
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typically used when an external (public) host needs to initiate a
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session with an internal (private) host. A customer needs to access a
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private service behind the routers public IP. A connection is
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established with the routers public IP address on a well known port and
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thus all traffic for this port is rewritten to address the internal
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(private) host.
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.. _bidirectional-nat:
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Bidirectional NAT
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^^^^^^^^^^^^^^^^^
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This is a common scenario where both :ref:`source-nat` and
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:ref:`destination-nat` are configured at the same time. It's commonly
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used when internal (private) hosts need to establish a connection with
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external resources and external systems need to access internal
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(private) resources.
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NAT, Routing, Firewall Interaction
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----------------------------------
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There is a very nice picture/explanation in the Vyatta documentation
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which should be rewritten here.
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NAT Ruleset
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-----------
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:abbr:`NAT (Network Address Translation)` is configured entirely on a
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series of so called `rules`. Rules are numbered and evaluated by the
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underlying OS in numerical order! The rule numbers can be changes by
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utilizing the :cfgcmd:`rename` and :cfgcmd:`copy` commands.
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.. note:: Changes to the NAT system only affect newly established
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connections. Already established connections are not affected.
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.. hint:: When designing your NAT ruleset leave some space between
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consecutive rules for later extension. Your ruleset could start with
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numbers 10, 20, 30. You thus can later extend the ruleset and place
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new rules between existing ones.
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Rules will be created for both :ref:`source-nat` and
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:ref:`destination-nat`.
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For :ref:`bidirectional-nat` a rule for both :ref:`source-nat` and
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:ref:`destination-nat` needs to be created.
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.. _traffic-filters:
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Traffic Filters
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---------------
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Traffic Filters are used to control which packets will have the defined
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NAT rules applied. Five different filters can be applied within a NAT
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rule.
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* **outbound-interface** - applicable only to :ref:`source-nat`. It
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configures the interface which is used for the outside traffic that
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this translation rule applies to.
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Example:
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.. code-block:: none
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set nat source rule 20 outbound-interface eth0
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* **inbound-interface** - applicable only to :ref:`destination-nat`. It
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configures the interface which is used for the inside traffic the
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translation rule applies to.
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Example:
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.. code-block:: none
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set nat destination rule 20 inbound-interface eth1
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* **protocol** - specify which types of protocols this translation rule
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applies to. Only packets matching the specified protocol are NATed.
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By default this applies to `all` protocols.
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Example:
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* Set SNAT rule 20 to only NAT TCP and UDP packets
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* Set DNAT rule 20 to only NAT UDP packets
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.. code-block:: none
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set nat source rule 20 protocol tcp_udp
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set nat destination rule 20 protocol udp
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* **source** - specifies which packets the NAT translation rule applies
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to based on the packets source IP address and/or source port. Only
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matching packets are considered for NAT.
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Example:
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* Set SNAT rule 20 to only NAT packets arriving from the 192.0.2.0/24
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network
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* Set SNAT rule 30 to only NAT packets arriving from the 203.0.113.0/24
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network with a source port of 80 and 443
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.. code-block:: none
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set nat source rule 20 source address 192.0.2.0/24
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set nat source rule 30 source address 203.0.113.0/24
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set nat source rule 30 source port 80,443
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* **destination** - specify which packets the translation will be
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applied to, only based on the destination address and/or port number
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configured.
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.. note:: If no destination is specified the rule will match on any
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destination address and port.
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Example:
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* Configure SNAT rule (40) to only NAT packets with a destination
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address of 192.0.2.1.
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.. code-block:: none
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set nat source rule 40 destination address 192.0.2.1
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Address Conversion
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------------------
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Every NAT rule has a translation command defined. The address defined
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for the translation is the address used when the address information in
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a packet is replaced.
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Source Address
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^^^^^^^^^^^^^^
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For :ref:`source-nat` rules the packets source address will be replaced
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with the address specified in the translation command. A port
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translation can also be specified and is part of the translation
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address.
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.. note:: The translation address must be set to one of the available
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addresses on the configured `outbound-interface` or it must be set to
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`masquerade` which will use the primary IP address of the
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`outbound-interface` as its translation address.
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.. note:: When using NAT for a large number of host systems it
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recommended that a minimum of 1 IP address is used to NAT every 256
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private host systems. This is due to the limit of 65,000 port numbers
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available for unique translations and a reserving an average of
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200-300 sessions per host system.
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Example:
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* Define a discrete source IP address of 100.64.0.1 for SNAT rule 20
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* Use address `masquerade` (the interfaces primary address) on rule 30
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* For a large amount of private machines behind the NAT your address
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pool might to be bigger. Use any address in the range 100.64.0.10 -
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100.64.0.20 on SNAT rule 40 when doing the translation
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.. code-block:: none
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set nat source rule 20 translation address 100.64.0.1
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set nat source rule 30 translation address 'masquerade'
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set nat source rule 40 translation address 100.64.0.10-100.64.0.20
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Destination Address
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^^^^^^^^^^^^^^^^^^^
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For :ref:`destination-nat` rules the packets destination address will be
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replaced by the specified address in the `translation address` command.
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Example:
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* DNAT rule 10 replaces the destination address of an inbound packet
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with 192.0.2.10
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.. code-block:: none
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set nat destination rule 10 translation address 192.0.2.10
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Also, in :ref:`destination-nat`, redirection to localhost is supported.
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The redirect statement is a special form of dnat which always translates
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the destination address to the local host’s one.
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Example of redirection:
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.. code-block:: none
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set nat destination rule 10 translation redirect port 22
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NAT Load Balance
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----------------
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Advanced configuration can be used in order to apply source or destination NAT,
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and within a single rule, be able to define multiple translated addresses,
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so NAT balances the translations among them.
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NAT Load Balance uses an algorithm that generates a hash and based on it, then
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it applies corresponding translation. This hash can be generated randomly, or
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can use data from the ip header: source-address, destination-address,
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source-port and/or destination-port. By default, it will generate the hash
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randomly.
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When defining the translated address, called ``backends``, a ``weight`` must
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be configured. This lets the user define load balance distribution according
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to their needs. Them sum of all the weights defined for the backends should
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be equal to 100. In oder words, the weight defined for the backend is the
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percentage of the connections that will receive such backend.
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.. cfgcmd:: set nat [source | destination] rule <rule> load-balance hash
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[source-address | destination-address | source-port | destination-port
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| random]
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.. cfgcmd:: set nat [source | destination] rule <rule> load-balance backend
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<x.x.x.x> weight <1-100>
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Configuration Examples
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======================
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To setup SNAT, we need to know:
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* The internal IP addresses we want to translate
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* The outgoing interface to perform the translation on
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* The external IP address to translate to
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In the example used for the Quick Start configuration above, we
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demonstrate the following configuration:
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.. code-block:: none
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set nat source rule 100 outbound-interface 'eth0'
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set nat source rule 100 source address '192.168.0.0/24'
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set nat source rule 100 translation address 'masquerade'
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Which generates the following configuration:
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.. code-block:: none
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rule 100 {
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outbound-interface eth0
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source {
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address 192.168.0.0/24
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}
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translation {
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address masquerade
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}
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}
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In this example, we use **masquerade** as the translation address
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instead of an IP address. The **masquerade** target is effectively an
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alias to say "use whatever IP address is on the outgoing interface",
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rather than a statically configured IP address. This is useful if you
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use DHCP for your outgoing interface and do not know what the external
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address will be.
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When using NAT for a large number of host systems it recommended that a
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minimum of 1 IP address is used to NAT every 256 host systems. This is
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due to the limit of 65,000 port numbers available for unique
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translations and a reserving an average of 200-300 sessions per host
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system.
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Example: For an ~8,000 host network a source NAT pool of 32 IP addresses
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is recommended.
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A pool of addresses can be defined by using a hyphen between two IP
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addresses:
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.. code-block:: none
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set nat source rule 100 translation address '203.0.113.32-203.0.113.63'
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.. _avoidng_leaky_nat:
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Avoiding "leaky" NAT
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--------------------
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Linux netfilter will not NAT traffic marked as INVALID. This often
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confuses people into thinking that Linux (or specifically VyOS) has a
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broken NAT implementation because non-NATed traffic is seen leaving an
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external interface. This is actually working as intended, and a packet
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capture of the "leaky" traffic should reveal that the traffic is either
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an additional TCP "RST", "FIN,ACK", or "RST,ACK" sent by client systems
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after Linux netfilter considers the connection closed. The most common
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is the additional TCP RST some host implementations send after
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terminating a connection (which is implementation-specific).
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In other words, connection tracking has already observed the connection
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be closed and has transition the flow to INVALID to prevent attacks from
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attempting to reuse the connection.
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You can avoid the "leaky" behavior by using a firewall policy that drops
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"invalid" state packets.
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Having control over the matching of INVALID state traffic, e.g. the
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ability to selectively log, is an important troubleshooting tool for
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observing broken protocol behavior. For this reason, VyOS does not
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globally drop invalid state traffic, instead allowing the operator to
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make the determination on how the traffic is handled.
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.. _hairpin_nat_reflection:
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Hairpin NAT/NAT Reflection
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--------------------------
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A typical problem with using NAT and hosting public servers is the
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ability for internal systems to reach an internal server using it's
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external IP address. The solution to this is usually the use of
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split-DNS to correctly point host systems to the internal address when
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requests are made internally. Because many smaller networks lack DNS
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infrastructure, a work-around is commonly deployed to facilitate the
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traffic by NATing the request from internal hosts to the source address
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of the internal interface on the firewall.
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This technique is commonly referred to as NAT Reflection or Hairpin NAT.
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Example:
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* Redirect Microsoft RDP traffic from the outside (WAN, external) world
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via :ref:`destination-nat` in rule 100 to the internal, private host
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192.0.2.40.
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* Redirect Microsoft RDP traffic from the internal (LAN, private)
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network via :ref:`destination-nat` in rule 110 to the internal,
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private host 192.0.2.40. We also need a :ref:`source-nat` rule 110 for
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the reverse path of the traffic. The internal network 192.0.2.0/24 is
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reachable via interface `eth0.10`.
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.. code-block:: none
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set nat destination rule 100 description 'Regular destination NAT from external'
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set nat destination rule 100 destination port '3389'
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set nat destination rule 100 inbound-interface 'pppoe0'
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set nat destination rule 100 protocol 'tcp'
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set nat destination rule 100 translation address '192.0.2.40'
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set nat destination rule 110 description 'NAT Reflection: INSIDE'
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set nat destination rule 110 destination port '3389'
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set nat destination rule 110 inbound-interface 'eth0.10'
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set nat destination rule 110 protocol 'tcp'
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set nat destination rule 110 translation address '192.0.2.40'
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set nat source rule 110 description 'NAT Reflection: INSIDE'
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set nat source rule 110 destination address '192.0.2.0/24'
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set nat source rule 110 outbound-interface 'eth0.10'
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set nat source rule 110 protocol 'tcp'
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set nat source rule 110 source address '192.0.2.0/24'
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set nat source rule 110 translation address 'masquerade'
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Which results in a configuration of:
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.. code-block:: none
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vyos@vyos# show nat
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destination {
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rule 100 {
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description "Regular destination NAT from external"
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destination {
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port 3389
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}
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inbound-interface pppoe0
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protocol tcp
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translation {
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address 192.0.2.40
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}
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}
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rule 110 {
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description "NAT Reflection: INSIDE"
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destination {
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port 3389
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}
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inbound-interface eth0.10
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protocol tcp
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translation {
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address 192.0.2.40
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}
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}
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}
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source {
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rule 110 {
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description "NAT Reflection: INSIDE"
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destination {
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address 192.0.2.0/24
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}
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outbound-interface eth0.10
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protocol tcp
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source {
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address 192.0.2.0/24
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}
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translation {
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address masquerade
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}
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}
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}
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Destination NAT
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---------------
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DNAT is typically referred to as a **Port Forward**. When using VyOS as
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a NAT router and firewall, a common configuration task is to redirect
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incoming traffic to a system behind the firewall.
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In this example, we will be using the example Quick Start configuration
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above as a starting point.
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To setup a destination NAT rule we need to gather:
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* The interface traffic will be coming in on;
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* The protocol and port we wish to forward;
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* The IP address of the internal system we wish to forward traffic to.
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In our example, we will be forwarding web server traffic to an internal
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web server on 192.168.0.100. HTTP traffic makes use of the TCP protocol
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on port 80. For other common port numbers, see:
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https://en.wikipedia.org/wiki/List_of_TCP_and_UDP_port_numbers
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Our configuration commands would be:
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.. code-block:: none
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set nat destination rule 10 description 'Port Forward: HTTP to 192.168.0.100'
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set nat destination rule 10 destination port '80'
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set nat destination rule 10 inbound-interface 'eth0'
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set nat destination rule 10 protocol 'tcp'
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set nat destination rule 10 translation address '192.168.0.100'
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Which would generate the following NAT destination configuration:
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.. code-block:: none
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nat {
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destination {
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rule 10 {
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description "Port Forward: HTTP to 192.168.0.100"
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destination {
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port 80
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}
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inbound-interface eth0
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protocol tcp
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translation {
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address 192.168.0.100
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}
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}
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}
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}
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|
||
.. note:: If forwarding traffic to a different port than it is arriving
|
||
on, you may also configure the translation port using
|
||
`set nat destination rule [n] translation port`.
|
||
|
||
This establishes our Port Forward rule, but if we created a firewall
|
||
policy it will likely block the traffic.
|
||
|
||
It is important to note that when creating firewall rules that the DNAT
|
||
translation occurs **before** traffic traverses the firewall. In other
|
||
words, the destination address has already been translated to
|
||
192.168.0.100.
|
||
|
||
So in our firewall policy, we want to allow traffic coming in on the
|
||
outside interface, destined for TCP port 80 and the IP address of
|
||
192.168.0.100.
|
||
|
||
.. code-block:: none
|
||
|
||
set firewall name OUTSIDE-IN rule 20 action 'accept'
|
||
set firewall name OUTSIDE-IN rule 20 destination address '192.168.0.100'
|
||
set firewall name OUTSIDE-IN rule 20 destination port '80'
|
||
set firewall name OUTSIDE-IN rule 20 protocol 'tcp'
|
||
set firewall name OUTSIDE-IN rule 20 state new 'enable'
|
||
|
||
This would generate the following configuration:
|
||
|
||
.. code-block:: none
|
||
|
||
rule 20 {
|
||
action accept
|
||
destination {
|
||
address 192.168.0.100
|
||
port 80
|
||
}
|
||
protocol tcp
|
||
state {
|
||
new enable
|
||
}
|
||
}
|
||
|
||
.. note::
|
||
|
||
If you have configured the `INSIDE-OUT` policy, you will need to add
|
||
additional rules to permit inbound NAT traffic.
|
||
|
||
1-to-1 NAT
|
||
----------
|
||
|
||
Another term often used for DNAT is **1-to-1 NAT**. For a 1-to-1 NAT
|
||
configuration, both DNAT and SNAT are used to NAT all traffic from an
|
||
external IP address to an internal IP address and vice-versa.
|
||
|
||
Typically, a 1-to-1 NAT rule omits the destination port (all ports) and
|
||
replaces the protocol with either **all** or **ip**.
|
||
|
||
Then a corresponding SNAT rule is created to NAT outgoing traffic for
|
||
the internal IP to a reserved external IP. This dedicates an external IP
|
||
address to an internal IP address and is useful for protocols which
|
||
don't have the notion of ports, such as GRE.
|
||
|
||
Here's an extract of a simple 1-to-1 NAT configuration with one internal
|
||
and one external interface:
|
||
|
||
.. code-block:: none
|
||
|
||
set interfaces ethernet eth0 address '192.168.1.1/24'
|
||
set interfaces ethernet eth0 description 'Inside interface'
|
||
set interfaces ethernet eth1 address '192.0.2.30/24'
|
||
set interfaces ethernet eth1 description 'Outside interface'
|
||
set nat destination rule 2000 description '1-to-1 NAT example'
|
||
set nat destination rule 2000 destination address '192.0.2.30'
|
||
set nat destination rule 2000 inbound-interface 'eth1'
|
||
set nat destination rule 2000 translation address '192.168.1.10'
|
||
set nat source rule 2000 description '1-to-1 NAT example'
|
||
set nat source rule 2000 outbound-interface 'eth1'
|
||
set nat source rule 2000 source address '192.168.1.10'
|
||
set nat source rule 2000 translation address '192.0.2.30'
|
||
|
||
Firewall rules are written as normal, using the internal IP address as
|
||
the source of outbound rules and the destination of inbound rules.
|
||
|
||
NAT before VPN
|
||
--------------
|
||
|
||
Some application service providers (ASPs) operate a VPN gateway to
|
||
provide access to their internal resources, and require that a
|
||
connecting organisation translate all traffic to the service provider
|
||
network to a source address provided by the ASP.
|
||
|
||
Load Balance
|
||
------------
|
||
Here we provide two examples on how to apply NAT Load Balance.
|
||
|
||
First scenario: apply destination NAT for all HTTP traffic comming through
|
||
interface eth0, and user 4 backends. First backend should received 30% of
|
||
the request, second backend should get 20%, third 15% and the fourth 35%
|
||
We will use source and destination address for hash generation.
|
||
|
||
.. code-block:: none
|
||
|
||
set nat destination rule 10 inbound-interface eth0
|
||
set nat destination rule 10 protocol tcp
|
||
set nat destination rule 10 destination port 80
|
||
set nat destination rule 10 load-balance hash source-address
|
||
set nat destination rule 10 load-balance hash destination-address
|
||
set nat destination rule 10 laod-balance backend 198.51.100.101 weight 30
|
||
set nat destination rule 10 laod-balance backend 198.51.100.102 weight 20
|
||
set nat destination rule 10 laod-balance backend 198.51.100.103 weight 15
|
||
set nat destination rule 10 laod-balance backend 198.51.100.104 weight 35
|
||
|
||
Second scenario: apply source NAT for all outgoing connections from
|
||
LAN 10.0.0.0/8, using 3 public addresses and equal distribution.
|
||
We will generate the hash randomly.
|
||
|
||
.. code-block:: none
|
||
|
||
set nat source rule 10 outbound-interface eth0
|
||
set nat source rule 10 source address 10.0.0.0/8
|
||
set nat source rule 10 load-balance hash random
|
||
set nat source rule 10 load-balance backend 192.0.2.251 weight 33
|
||
set nat source rule 10 load-balance backend 192.0.2.252 weight 33
|
||
set nat source rule 10 load-balance backend 192.0.2.253 weight 34
|
||
|
||
Example Network
|
||
^^^^^^^^^^^^^^^
|
||
|
||
Here's one example of a network environment for an ASP.
|
||
The ASP requests that all connections from this company should come from
|
||
172.29.41.89 - an address that is assigned by the ASP and not in use at
|
||
the customer site.
|
||
|
||
.. figure:: /_static/images/nat_before_vpn_topology.png
|
||
:scale: 100 %
|
||
:alt: NAT before VPN Topology
|
||
|
||
NAT before VPN Topology
|
||
|
||
|
||
Configuration
|
||
^^^^^^^^^^^^^
|
||
|
||
The required configuration can be broken down into 4 major pieces:
|
||
|
||
* A dummy interface for the provider-assigned IP;
|
||
* NAT (specifically, Source NAT);
|
||
* IPSec IKE and ESP Groups;
|
||
* IPSec VPN tunnels.
|
||
|
||
|
||
Dummy interface
|
||
"""""""""""""""
|
||
|
||
The dummy interface allows us to have an equivalent of the Cisco IOS
|
||
Loopback interface - a router-internal interface we can use for IP
|
||
addresses the router must know about, but which are not actually
|
||
assigned to a real network.
|
||
|
||
We only need a single step for this interface:
|
||
|
||
.. code-block:: none
|
||
|
||
set interfaces dummy dum0 address '172.29.41.89/32'
|
||
|
||
NAT Configuration
|
||
"""""""""""""""""
|
||
|
||
.. code-block:: none
|
||
|
||
set nat source rule 110 description 'Internal to ASP'
|
||
set nat source rule 110 destination address '172.27.1.0/24'
|
||
set nat source rule 110 outbound-interface 'any'
|
||
set nat source rule 110 source address '192.168.43.0/24'
|
||
set nat source rule 110 translation address '172.29.41.89'
|
||
set nat source rule 120 description 'Internal to ASP'
|
||
set nat source rule 120 destination address '10.125.0.0/16'
|
||
set nat source rule 120 outbound-interface 'any'
|
||
set nat source rule 120 source address '192.168.43.0/24'
|
||
set nat source rule 120 translation address '172.29.41.89'
|
||
|
||
IPSec IKE and ESP
|
||
"""""""""""""""""
|
||
|
||
The ASP has documented their IPSec requirements:
|
||
|
||
* IKE Phase:
|
||
|
||
* aes256 Encryption
|
||
* sha256 Hashes
|
||
|
||
* ESP Phase:
|
||
|
||
* aes256 Encryption
|
||
* sha256 Hashes
|
||
* DH Group 14
|
||
|
||
|
||
Additionally, we want to use VPNs only on our eth1 interface (the
|
||
external interface in the image above)
|
||
|
||
.. code-block:: none
|
||
|
||
set vpn ipsec ike-group my-ike key-exchange 'ikev1'
|
||
set vpn ipsec ike-group my-ike lifetime '7800'
|
||
set vpn ipsec ike-group my-ike proposal 1 dh-group '14'
|
||
set vpn ipsec ike-group my-ike proposal 1 encryption 'aes256'
|
||
set vpn ipsec ike-group my-ike proposal 1 hash 'sha256'
|
||
|
||
set vpn ipsec esp-group my-esp lifetime '3600'
|
||
set vpn ipsec esp-group my-esp mode 'tunnel'
|
||
set vpn ipsec esp-group my-esp pfs 'disable'
|
||
set vpn ipsec esp-group my-esp proposal 1 encryption 'aes256'
|
||
set vpn ipsec esp-group my-esp proposal 1 hash 'sha256'
|
||
|
||
set vpn ipsec interface 'eth1'
|
||
|
||
IPSec VPN Tunnels
|
||
"""""""""""""""""
|
||
|
||
We'll use the IKE and ESP groups created above for this VPN. Because we
|
||
need access to 2 different subnets on the far side, we will need two
|
||
different tunnels. If you changed the names of the ESP group and IKE
|
||
group in the previous step, make sure you use the correct names here
|
||
too.
|
||
|
||
.. code-block:: none
|
||
|
||
set vpn ipsec authentication psk vyos id '203.0.113.46'
|
||
set vpn ipsec authentication psk vyos id '198.51.100.243'
|
||
set vpn ipsec authentication psk vyos secret 'MYSECRETPASSWORD'
|
||
set vpn ipsec site-to-site peer branch authentication local-id '203.0.113.46'
|
||
set vpn ipsec site-to-site peer branch authentication mode 'pre-shared-secret'
|
||
set vpn ipsec site-to-site peer branch authentication remote-id '198.51.100.243'
|
||
set vpn ipsec site-to-site peer branch connection-type 'initiate'
|
||
set vpn ipsec site-to-site peer branch default-esp-group 'my-esp'
|
||
set vpn ipsec site-to-site peer branch ike-group 'my-ike'
|
||
set vpn ipsec site-to-site peer branch ikev2-reauth 'inherit'
|
||
set vpn ipsec site-to-site peer branch local-address '203.0.113.46'
|
||
set vpn ipsec site-to-site peer branch remote-address '198.51.100.243'
|
||
set vpn ipsec site-to-site peer branch tunnel 0 local prefix '172.29.41.89/32'
|
||
set vpn ipsec site-to-site peer branch tunnel 0 remote prefix '172.27.1.0/24'
|
||
set vpn ipsec site-to-site peer branch tunnel 1 local prefix '172.29.41.89/32'
|
||
set vpn ipsec site-to-site peer branch tunnel 1 remote prefix '10.125.0.0/16'
|
||
|
||
Testing and Validation
|
||
""""""""""""""""""""""
|
||
|
||
If you've completed all the above steps you no doubt want to see if it's
|
||
all working.
|
||
|
||
Start by checking for IPSec SAs (Security Associations) with:
|
||
|
||
.. code-block:: none
|
||
|
||
$ show vpn ipsec sa
|
||
|
||
Peer ID / IP Local ID / IP
|
||
------------ -------------
|
||
198.51.100.243 203.0.113.46
|
||
|
||
Tunnel State Bytes Out/In Encrypt Hash NAT-T A-Time L-Time Proto
|
||
------ ----- ------------- ------- ---- ----- ------ ------ -----
|
||
0 up 0.0/0.0 aes256 sha256 no 1647 3600 all
|
||
1 up 0.0/0.0 aes256 sha256 no 865 3600 all
|
||
|
||
That looks good - we defined 2 tunnels and they're both up and running.
|