route(1M)																 route(1M)

NAME

       route - manually manipulate the routing tables

SYNOPSIS

       pmtu] destination mask] gateway [count] src]

       pmtu] v6destination [ / prefix] v6gateway [count] v6src]

       destination mask] gateway [count] src]

       v6destination [ / prefix] v6gateway [count] v6src]

DESCRIPTION

       The command manipulates the network routing tables manually.  You must have appropriate privileges.

   Subcommands
       The following subcommands are supported.

	      Add the specified host or network route to the network routing table.
			     If the route already exists, a message is printed and nothing changes.

	      Delete the specified host or network route from the network routing table.

   Options and Arguments
       recognizes the following options and arguments.

	      Specifies an IPv6 route.
			     When  this  option  is used, the destination and the gateway must have IPv6 addresses.  When this option is not used,
			     the command defaults to an IPv4 route and the destination and the gateway must have IPv4 addresses.

	      Deletes all route table entries added through route command or
			     through an ioctl.	If this is used with one of the subcommands, the entries are deleted before the subcommand is pro-
			     cessed.

	      Print any host and network addresses in Internet "dot" notation
			     for IPv4 and in "colon" notation for IPv6, except for the default network address, which is printed as

	      Specifies a path maximum transmission unit (MTU) value for
			     a	static	route.	 The minimum value allowed is 68 bytes for IPv4 and 1280 bytes for IPv6; the maximum is the MTU of
			     the outgoing interface for this route.  This option can be applied to both host and network routes.

	       or
	      The type of    destination address.  If this argument is omitted, routes to a particular host are distinguished from those to a net-
			     work  by  interpreting  the  Internet  address associated with destination.  For IPv4, if the destination has a local
			     address part of the route is assumed to be to a network; otherwise, it is treated as a route to a host.  For IPv6, if
			     the  destination  has  an	address  that  is less than 128 bits, including any leading and trailing 0's, the route is
			     assumed to be a network; otherwise, it is treated as a route to a	host.	An  exception  is  the	IPv6  "Unspecified
			     Address", typically represented as which is always interpreted as the default network route.

	      destination    (inet only) The destination host system where the packets will be routed.	destination can be one of the following:

				  o  A host name (the official name or an alias, see gethostent(3N)).
				  o  A network name (the official name or an alias, see getnetent(3N)).
				  o  An Internet address in "dot" notation (see inet(3N)).
				  o  The keyword which signifies the wildcard gateway route (see routing(7)).

	      v6destination  (inet6  only)  The destination host system where the packets will be routed.  v6destination can be one of the follow-
			     ing:

				  o  A host name (the official name or an alias, see getaddrinfo(3N)).
				  o  An IPv6 address in "colon" notation (see inet6(3N)).
				  o  The keyword which signifies the wildcard gateway route.

	      prefix	     (inet6 only) The prefix is an integer between 0 and 128 inclusive.  It specifies how many of the leftmost	contiguous
			     bits of the v6destination address comprise the prefix.  Its format is similar to the CIDR notation in IPv4.  A prefix
			     of 0 would be a default route.  If the prefix is omitted when adding a network route, then the prefix would be 64	by
			     default.	It  is	advisable  to  specify	the  prefix when an IPv6 network route is added.  The prefix option can be
			     applied to network routes only.

	      (inet only)    The mask that will be bit-wise ANDed with destination to yield a net address where the packets will be routed.   mask
			     can  be  specified  as  a	single hexadecimal number with a leading with a "dot-notation" Internet address, or with a
			     pseudo-network name listed in the network table (see networks(4)).  The length of the mask, which is  the	number	of
			     contiguous  1's starting from the left-most bit position of the 32-bit field, can be shorter than the default network
			     mask for the destination address.	(See routing(7)).  If the option is not given, mask for the route will be  derived
			     from  the	associated with the local interfaces.  (See ifconfig(1M)).  mask will be defaulted to the longest of those
			     local interfaces that have the same network address.  If there is not any local interface that has the  same  network
			     address, then mask will default to the default value of network mask of destination.

	      gateway	     (inet only) The gateway through which the destination is reached.	gateway can be one of the following:

				  o  A host name (the official name or an alias, see gethostent(3N)).
				  o  An Internet address in "dot" notation (see inet(3N)).

	      v6gateway      (inet6 only) The gateway through which the destination is reached.  v6gateway can be one of the following:

				  o  A host name (the official name or an alias, see getaddrinfo(3N)).
				  o  An IPv6 address in "colon" notation (see inet6(3N)).

	      count	     An  integer  that indicates whether the gateway is a remote host or the local host.  If the route leads to a destina-
			     tion through a remote gateway, count should be a number greater than 0.  If the route leads to  destination  and  the
			     gateway  is the local host, count should be 0.  The default for count is zero.  The result is not defined if count is
			     negative.

	      (inet only)    The specified source address.  This option allows traffic to be directed to a selected interface instead  of  to  the
			     system  default.	When the Strong ES Model is set to 1, this option allows going out of an interface that would nor-
			     mally be blocked.	Note that the gateway and source must be in the same subnet.

			     src can be one of the following:

				  o  A host name (the official name or an alias, see gethostent(3N)).
				  o  An Internet address in "dot" notation (see inet(3N)).

	      (inet6 only)   The specified source address.  This option allows traffic to be directed to a selected interface instead  of  to  the
			     system default.  Note that the gateway and source must be in the same subnet.

			     v6src can be one of the following:

				  o  A host name (the official name or an alias, see getaddrinfo(3N)).
				  o  An IPv6 address in "colon" notation (see inet6(3N)).

   Operation
       All  symbolic names specified for a destination or gateway are looked up first as a host name using for IPv4 and for IPv6; if the host name
       is not found, the destination is searched for as a network name using for IPv4 only.  destination and gateway can be in "dot" notation (see
       inet(3N)).  v6destination and v6gateway can be in "colon" notation (see inet6(3N)).

       If  the	option	is  not specified, any host and network addresses are displayed symbolically according to the name returned by and respec-
       tively, except for the default network address (printed as and addresses that have unknown names.  Addresses with unknown names are printed
       in Internet "dot" notation (see inet(3N)).

       If  the	option	is specified, any host and network addresses are printed in Internet "dot" notation except for the default network address
       which is printed as

       If the option is specified, deletes all route table entries that specify a remote host for a gateway.  If it is used with one of  the  sub-
       commands described above, the entries are deleted before the subcommand is processed.

       Path  MTU  Discovery is a technique for discovering the maximum size of an IP datagram that can be sent on an internet path without causing
       datagram fragmentation in the intermediate routers.  In essence, a source host that utilizes this technique initially sends  out  datagrams
       up  to  the  the  size of the outgoing interface.  The Don't Fragment (DF) bit in the IP datagram header is set.  As an intermediate router
       that supports Path MTU Discovery receives a datagram that is too large to be forwarded in one piece to the next-hop router and the  DF  bit
       is set, the router will discard the datagram and send an ICMP Destination Unreachable message with a code meaning "fragmentation needed and
       DF set".  The ICMP message will also contain the MTU of the next-hop router.  When the source host receives the ICMP  message,  it  reduces
       the  path  MTU of the route to the MTU in the ICMP message.  With this technique, the host route in the source host for this path will con-
       tain the proper MTU.

       The pmtu option is useful only if you know the network environment well enough to enter an appropriate pmtu for a host  or  network  route.
       IP  will  fragment a datagram to the pmtu specified for the route on the local host before sending the datagram out to the remote.  It will
       avoid fragmentation by routers along the path, if the pmtu specified in the command is correct.

       can be used to find the pmtu information for the route to a remote host.  The pmtu information in the routing table can be  displayed  with
       the command (see netstat(1)).

       The  loopback  interface  is automatically configured when the system boots with the TCP/IP software.  For IPv4, the default IP address and
       netmask of the loopback interface are 127.0.0.1 and 255.0.0.0, respectively.  For IPv6, the default IP address and prefix of  the  loopback
       interface are ::1 and 128, respectively.

       When  is configured, the 127.0.0.0 loopback route for IPv4 and the ::1 loopback route for IPv6 are set up automatically so that packets for
       any 127.*.*.* address and ::1 will loop back to the local host.	Users cannot add or delete any 127.*.*.* or ::1 loopback routes.

   IPv6 Operation
       The keyword is required for adding or deleting IPv6 routes.

       Examples

       add a direct IPv6 host route

       add an indirect IPv6 (sub)network route

       delete an indirect IPv6 (sub)network route

   Output
	      The specified route is being added to the tables.

	      The specified route is being deleted from the tables.

   Flags
       The values of the count and destination type fields in the command determine the presence of the and flags in  the  display  and  thus  the
       route type, as shown in the following table.

	      Count   Destination Type	 Flags		   Route Type
	      ------------------------------------------------------------------
	       =0	  network	  U	 Route	to  a  network directly
						 from the local host
	       >0	  network	  UG	 Route to a network  through  a
						 remote host gateway
	       =0	    host	  UH	 Route	 to   a   remote   host
						 directly from the local host
	       >0	    host	  UGH	 Route to a remote host through
						 a remote host gateway
	       =0	  default	  U	 Wildcard  route  directly from
						 the local host
	       >0	  default	  UG	 Wildcard   route   through   a
						 remote host gateway
	      ------------------------------------------------------------------

DIAGNOSTICS

       The following error diagnostics can be displayed:

       The specified entry is already in the routing table.

       The specified route was not in the routing table.

       Routes for any 127.*.*.* loopback destination cannot be added or deleted.

WARNINGS

       Reciprocal  commands  must  be executed on the local host, the destination host, and all intermediate hosts if routing is to succeed in the
       cases of virtual circuit connections or bidirectional datagram transfers.

       The HP-UX implementation of does not presently support a subcommand.

AUTHOR

       was developed by the University of California, Berkeley.

FILES

SEE ALSO

       netstat(1), ifconfig(1M), ndd(1M), ping(1M), getsockopt(2), recv(2), send(2),  getaddrinfo(3N),	gethostent(3N),  getnetent(3N),  inet(3N),
       inet6(3N), routing(7), route(7P).

																	 route(1M)