TAYGA.CONF(5)															     TAYGA.CONF(5)

NAME

       tayga.conf - configuration file of the TAYGA stateless NAT64 daemon

DESCRIPTION

       This  file  contains the configuration parameters for the TAYGA stateless NAT64 daemon.	It must exist and contain the mandatory configura-
       tion items or TAYGA will refuse to run.

       The configuration directives are listed below.  With the exception of the map directive, only one instance of each directive may appear	in
       tayga.conf.

       tun-device device
	      Name of the network interface that will be created by the kernel TUN module for TAYGA to exchange IPv4 and IPv6 packets with the in-
	      kernel TCP/IP stack.  If device does not already exist as a persistent interface (created by the --mktun flag to tayga(8), for exam-
	      ple), it will be created automatically when the TAYGA daemon starts and destroyed when the daemon exits.

	      Note  that  TAYGA  does  not  configure the host-side parameters of device.  This must be done by the system administrator using the
	      ifconfig(8), route(8), and/or ip(8) commands.

	      This configuration directive is mandatory.

       ipv4-addr ipv4_address
	      IPv4 address that TAYGA will use as the source address for ICMPv4 errors generated by the  translation  process.	 TAYGA	will  also
	      respond to ICMP echo requests (pings) at this address.

	      ipv4_address  is	permitted  to  overlap with the prefix specified in the dynamic-pool directive, in which case ipv4_address will be
	      removed from the pool of available addresses.

	      This configuration directive is mandatory.

       ipv6-addr ipv6_address
	      IPv6 address that TAYGA will use as the source address for ICMPv6 errors generated by the  translation  process.	 TAYGA	will  also
	      respond to ICMPv6 echo requests (pings) at this address.

	      This  configuration  directive is mandatory unless the NAT64 prefix is specified with the prefix directive, in which case TAYGA will
	      generate its IPv6 address by mapping the address specified in ipv4-addr into the NAT64 prefix.

       prefix ipv6_address/length
	      NAT64 prefix for mapping IPv4 addresses into the IPv6 address space.  TAYGA performs address translation as specified in	RFC  6052,
	      and only prefix lengths allowed in that document will be permitted in the prefix directive.

	      The  use	of  either a Network-Specific Prefix or the Well-Known Prefix (64:ff9b::/96) is allowed, however, as required by RFC 6052,
	      TAYGA will refuse to translate packets with a source or destination address composed of the Well-Known Prefix and a non-global  IPv4
	      address (10.x.x.x, 192.168.x.x, etc).

	      Use  of  the  prefix directive is optional.  If it is not specified, all addresses to be translated must be listed individually with
	      the map directive.

       map ipv4_address ipv6_address
	      Creates a static mapping between ipv4_address and ipv6_address to be used when translating IPv4 packets to IPv6 or IPv6  packets	to
	      IPv4.  Multiple map directives are permitted in the tayga.conf file.

	      ipv4_address  is	permitted  to  overlap with the prefix specified in the dynamic-pool directive, in which case ipv4_address will be
	      removed from the pool of available addresses.

	      ipv6_address must not overlap with the prefix specified in the prefix directive.

       dynamic-pool ipv4_address/length
	      Address prefix containing addresses available to be assigned to IPv6 hosts.  length must be  31  or  less,  as  the  lowest-numbered
	      address in the prefix is considered reserved and will not be used for dynamic assignment.

	      If  TAYGA  receives  an  IPv6 packet to be translated with an IPv6 source address that does not match any existing mapping rules (as
	      specified by the map directive or the prefix directive), TAYGA will create a dynamic mapping between the IPv6 address  and  an  IPv4
	      address  drawn  from  the prefix specified by the dynamic-pool directive.  This mapping will be valid for two hours and four minutes
	      after the last packet matching the mapping is translated.

	      The dynamic-pool directive is optional.  If it is not specified, all IPv6 addresses appearing in packets passing through TAYGA  must
	      match the NAT64 prefix or a static mapping rule.

       data-dir path
	      The absolute path of a directory where TAYGA should store its data files.  Presently the only data file that TAYGA will store is the
	      dynamic.map file, which tracks dynamic address assignments made from the dynamic pool.

	      path is also the directory that will be used as a chroot(2) "jail" if the --chroot command-line option is  specified  to	the  TAYGA
	      daemon.

	      The  TAYGA daemon must have full permissions (rwx) to path after it has dropped superuser privileges.  Generally this means that the
	      owner of path should be the user specified in the --user command-line option.

	      The data-dir directive is optional, but without it, dynamic mappings will be lost when the TAYGA daemon is stopped.   Also,  use	of
	      the --chroot command-line option will not be possible.

       strict-frag-hdr on|off|true|false|1|0
	      Flag  to	control  whether  TAYGA adds fragmentation headers to IPv6 packets that do not require fragmentation.  RFC 6145 stipulates
	      that the fragmentation header SHOULD be added to all translated packets when the sender has not set the DF (Don't Fragment) flag, to
	      indicate	that the sender allows fragmentation and may not support path MTU discovery.  Unfortunately, some firewall implementations
	      drop IPv6 packets that are fragmented into a single fragment, most notably Linux netfilter conntrack in kernels older than 2.6.34.

	      When strict-frag-hdr is set to true, on, or 1, fragmentation headers will be added to all translated packets where the DF bit in the
	      original packet is clear.  This is the RFC-complaint behavior.

	      When  strict-frag-hdr  is set to false, off, or 0, fragmentation headers will be suppressed when the translated packet fits entirely
	      within the IPv6 network MTU (1280 bytes).  This is the default behavior.

	      This setting does not affect packets that arrive at TAYGA already fragmented, or packets that must be fragmented to fit  within  the
	      IPv6 network MTU.

SEE ALSO

       tayga(8)
       <http://www.litech.org/tayga/>

TAYGA 0.9.2							     June 2011							     TAYGA.CONF(5)