[Xorp-users] Is it possible to configure the NAT on XORP??

Atanu Ghosh atanu at ICSI.Berkeley.EDU
Mon Sep 17 08:01:14 PDT 2007


Hi,

The getting started web page (http://www.xorp.org/getting_started.html)
contains examples of basic protocol configurations.

	 Atanu.

>>>>> "sanjeev" == sanjeev kumar <ror.sanjeev at gmail.com> writes:

    sanjeev>    Hi, I want to configure the NATing on XORP,but i do not
    sanjeev> know how ..could u please suggest me some steps.  One more
    sanjeev> thing : I want to test OSPF on two machines,both of them
    sanjeev> running XORP router..instead of say..i want to connect two
    sanjeev> machines back to back,then want to configure OSPF..Is it
    sanjeev> possible and provide me some guidance.  Thanks...  Sanjeev

    sanjeev>    On 9/14/07, xorp-users-request at xorp.org <
    sanjeev> xorp-users-request at xorp.org> wrote:

    sanjeev>      Send Xorp-users mailing list submissions to
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    sanjeev> s or, via email, send a message with subject or body 'help'
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    sanjeev> Today's Topics: 1. Re: Questions on OSPF
    sanjeev> (kristian at spritelink.net) 2. Re: Questions on OSPF (Atanu
    sanjeev> Ghosh) 3. Re: Questions on OSPF ( kristian at spritelink.net)
    sanjeev> 4. Re: Questions on OSPF (Atanu Ghosh) 5. Re: Questions on
    sanjeev> OSPF (kristian at spritelink.net) 6. Re: Unreachable default
    sanjeev> route. (Pavlin Radoslavov)
    sanjeev> -------------------------------------------------------------------
    sanjeev> --- Message: 1 Date: Thu, 13 Sep 2007 20:52:03 +0200 From:
    sanjeev> <kristian at spritelink.net > Subject: Re: [Xorp-users]
    sanjeev> Questions on OSPF To: atanu at ICSI.Berkeley.EDU Cc: xorp
    sanjeev> <xorp-users at xorp.org> Message-ID: <
    sanjeev> 4cfe4c3ba67b049473b1d94a88052842 at Mail.SpriteLink.NET>
    sanjeev> Content-Type: text/plain; charset="UTF-8" On Thu, 13 Sep
    sanjeev> 2007 11:51:32 -0700, Atanu Ghosh < atanu at icsi.berkeley.edu>
    sanjeev> wrote:
    >>>>>>> "Kristian" == Kristian Larsson <kristian at spritelink.net >
    sanjeev>      writes:
    >>
    Kristian> Hansi wrote:
    >> >> Hello All,
    >> >>
    >> >> I'm currently learning how to configure OSPFv2 on two XORP >>
    >> machines just to establish adjacency with one another. In
    sanjeev>      a p2p
    >> >> link type, is it still necessary to explicitly set the
    sanjeev>      'neighbor'
    >> >> parameter of each machine before adjacency is established?  >>
    >> Furthermore, would it be possible to set the router-id to
    sanjeev>      its
    >> >> loopback address? instead of say.. the ip address of the >>
    >> interface on which ospf will be used?
    >> 
    Kristian> The neighbor command is only useful if you are
    sanjeev>      using a
    Kristian> medium on which the routers cannot broadcast and
    sanjeev>      thus
    Kristian> cannot discover each other.  If you're using
    sanjeev>      ethernet
    Kristian> (which I presume from your NIC names) you do not
    sanjeev>      have to
    Kristian> use the neighbor statements. I would advice
    sanjeev>      configuring
    Kristian> the interfaces as link-type p2p as this avoids DR
    sanjeev>      election
    Kristian> and unnecessary CPU load.
    >>  I am fairly sure that it is necessary to use the neighbour
    sanjeev>      statements.  Are you serious?  I haven't used the XORP
    sanjeev> code in quite some time now.. but at least I thought XORP
    sanjeev> implemented the OSPF standard. AFAIK, that includes being
    sanjeev> able to discover neighbors and turn up adjacencies to
    sanjeev> them. Is this not the case?  Observe that he is running an
    sanjeev> Ethernet point-to-point link, ie, it is not a non-broadcast
    sanjeev> medium.  Or are you saying that you can't do link-type p2p
    sanjeev> without configuring neighbours ?  -K
    sanjeev> ------------------------------ Message: 2 Date: Thu, 13 Sep
    sanjeev> 2007 12:18:42 -0700 From: Atanu Ghosh
    sanjeev> <atanu at ICSI.Berkeley.EDU > Subject: Re: [Xorp-users]
    sanjeev> Questions on OSPF To: kristian at spritelink.net Cc: xorp
    sanjeev> <xorp-users at xorp.org> Message-ID: <
    sanjeev> 6353.1189711122 at tigger.icir.org>
    >>>>>> "kristian" == kristian <kristian at spritelink.net > writes:
    kristian> On Thu, 13 Sep 2007 11:51:32 -0700, Atanu Ghosh
    kristian> <atanu at icsi.berkeley.edu> wrote:
    >>>>>>>> "Kristian" == Kristian Larsson <
    sanjeev>      kristian at spritelink.net>
    >>>>>>>> writes:
    >>>
    Kristian> Hansi wrote:
    >>> >> Hello All,
    >>> >>
    >>> >> I'm currently learning how to configure OSPFv2 on two
    sanjeev>      XORP >>
    >>> machines just to establish adjacency with one another. In a
    sanjeev>      p2p
    >>> >> link type, is it still necessary to explicitly set the
    >>> 'neighbor' >> parameter of each machine before adjacency is
    >>> established?  >> Furthermore, would it be possible to set
    sanjeev>      the
    >>> router-id to its >> loopback address? instead of say.. the
    sanjeev>      ip
    >>> address of the >> interface on which ospf will be used?
    >>> 
    Kristian> The neighbor command is only useful if you are using
    sanjeev>      a
    Kristian> medium on which the routers cannot broadcast and thus
    Kristian> cannot discover each other.  If you're using ethernet
    Kristian> (which I presume from your NIC names) you do not have
    sanjeev>      to
    Kristian> use the neighbor statements. I would advice
    sanjeev>      configuring
    Kristian> the interfaces as link-type p2p as this avoids DR
    sanjeev>      election
    Kristian> and unnecessary CPU load.
    >>> I am fairly sure that it is necessary to use the neighbour
    >>> statements.
    kristian> Are you serious?  I haven't used the XORP code in
    sanjeev>      quite
    kristian> some time now.. but at least I thought XORP
    sanjeev>      implemented
    kristian> the OSPF standard. AFAIK, that includes being able to
    kristian> discover neighbors and turn up adjacencies to them.
    sanjeev>      Is
    kristian> this not the case?  Observe that he is running an
    sanjeev>      Ethernet
    kristian> point-to-point link, ie, it is not a non-broadcast
    sanjeev>      medium.
    kristian> Or are you saying that you can't do link-type p2p
    sanjeev>      without
    kristian> configuring neighbours ?
    sanjeev>      If the link-type is set to "broadcast" then the
    sanjeev> neighbours will be correctly discovered. If the link-type
    sanjeev> is set to "p2p" (Point-to-point) or "p2m"
    sanjeev> (Point-to-multipoint) then it is necessary to configure the
    sanjeev> neighbours. It has been argued that it should not be
    sanjeev> necessary to configure the neighbours if the routers are
    sanjeev> connected via a true Point-to-point link, but unfortunately
    sanjeev> even in this case it is necessary to configure the
    sanjeev> neighbour.  Atanu.  ------------------------------ Message:
    sanjeev> 3 Date: Thu, 13 Sep 2007 21:31:49 +0200 From:
    sanjeev> <kristian at spritelink.net> Subject: Re: [Xorp-users]
    sanjeev> Questions on OSPF To: atanu at ICSI.Berkeley.EDU Cc: xorp <
    sanjeev> xorp-users at xorp.org> Message-ID:
    sanjeev> <93a9e57afbb58e1bf4d6d68740135f89 at Mail.SpriteLink.NET>
    sanjeev> Content-Type: text/plain; charset="UTF-8" On Thu, 13 Sep
    sanjeev> 2007 12:18:42 -0700, Atanu Ghosh <atanu at icsi.berkeley.edu>
    sanjeev> wrote:
    >>>>>>> "kristian" == kristian < kristian at spritelink.net> writes:
    >>
    kristian> On Thu, 13 Sep 2007 11:51:32 -0700, Atanu Ghosh
    kristian> <atanu at icsi.berkeley.edu> wrote:
    >> >>>>>>> "Kristian" == Kristian Larsson
    sanjeev>      <kristian at spritelink.net>
    >> >>>>>>> writes:
    >> >>
    Kristian> Hansi wrote:
    >> >> >> Hello All,
    >> >> >>
    >> >> >> I'm currently learning how to configure OSPFv2 on two
    sanjeev>      XORP >>
    >> >> machines just to establish adjacency with one another. In
    sanjeev>      a p2p
    >> >> >> link type, is it still necessary to explicitly set the >>
    >> 'neighbor' >> parameter of each machine before adjacency
    sanjeev>      is
    >> >> established?  >> Furthermore, would it be possible to set
    sanjeev>      the
    >> >> router-id to its >> loopback address? instead of say.. the
    sanjeev>      ip
    >> >> address of the >> interface on which ospf will be used?
    >> >>
    Kristian> The neighbor command is only useful if you are
    sanjeev>      using a
    Kristian> medium on which the routers cannot broadcast and
    sanjeev>      thus
    Kristian> cannot discover each other.  If you're using
    sanjeev>      ethernet
    Kristian> (which I presume from your NIC names) you do not
    sanjeev>      have to
    Kristian> use the neighbor statements. I would advice
    sanjeev>      configuring
    Kristian> the interfaces as link-type p2p as this avoids DR
    sanjeev>      election
    Kristian> and unnecessary CPU load.
    >>  >> I am fairly sure that it is necessary to use the
    sanjeev>      neighbour
    >> >> statements.
    >> 
    kristian> Are you serious?  I haven't used the XORP code in
    sanjeev>      quite
    kristian> some time now.. but at least I thought XORP
    sanjeev>      implemented
    kristian> the OSPF standard. AFAIK, that includes being able
    sanjeev>      to
    kristian> discover neighbors and turn up adjacencies to them.
    sanjeev>      Is
    kristian> this not the case?  Observe that he is running an
    sanjeev>      Ethernet
    kristian> point-to-point link, ie, it is not a non-broadcast
    sanjeev>      medium.
    kristian> Or are you saying that you can't do link-type p2p
    sanjeev>      without
    kristian> configuring neighbours ?
    >>  If the link-type is set to "broadcast" then the neighbours will
    sanjeev>      be
    >> correctly discovered. If the link-type is set to "p2p"
    sanjeev>      (Point-to-point)
    >> or "p2m" (Point-to-multipoint) then it is necessary to configure
    sanjeev>      the
    >> neighbours. It has been argued that it should not be necessary to
    >> configure the neighbours if the routers are connected via a true
    >> Point-to-point link, but unfortunately even in this case it is
    sanjeev>      necessary
    >> to configure the neighbour.
    sanjeev>      Okey, that "kinda" makes sense. I apparently forgot or
    sanjeev> missed the conversation on this.  What I want to configure
    sanjeev> with link-type p2p is not whether or not the router should
    sanjeev> try to broadcast but if it should setup one of those
    sanjeev> virtual router thingys, hehe. I'm not very familiar with
    sanjeev> the terminology but (as you know) on a broadcast medium you
    sanjeev> first have a DR selection and all that and then you're
    sanjeev> gonna run your SPF. Since SPF can't handle the concept of a
    sanjeev> broadcast medium it creates a "virtual router" to represent
    sanjeev> the broadcast medium and connects all routers in that
    sanjeev> broadcast domain as adjacencies to the virtual router.
    sanjeev> When I configure 'isis network point-to-point' on a Cisco
    sanjeev> router I expect it to not setup one of these "virtual
    sanjeev> routers" in it's SPF topology. And this is different with
    sanjeev> XORP?  Perhaps the increase in simplicity to the SPF
    sanjeev> topology that 'isis network point-to-point' brings is so
    sanjeev> small that it's negligable. I think SPF runs take in the
    sanjeev> order of 10ms or so for a network with a couple of hundred
    sanjeev> routers on a normal routing engine these days.  -K
    sanjeev> ------------------------------ Message: 4 Date: Thu, 13 Sep
    sanjeev> 2007 14:58:01 -0700 From: Atanu Ghosh <
    sanjeev> atanu at ICSI.Berkeley.EDU> Subject: Re: [Xorp-users]
    sanjeev> Questions on OSPF To: kristian at spritelink.net Cc: xorp
    sanjeev> <xorp-users at xorp.org > Message-ID:
    sanjeev> <44891.1189720681 at tigger.icir.org>
    >>>>>> "kristian" == kristian < kristian at spritelink.net> writes:
    kristian> On Thu, 13 Sep 2007 12:18:42 -0700, Atanu Ghosh
    kristian> <atanu at icsi.berkeley.edu> wrote:
    >>>>>>>> "kristian" == kristian < kristian at spritelink.net>
    sanjeev>      writes:
    >>>
    kristian> On Thu, 13 Sep 2007 11:51:32 -0700, Atanu Ghosh <
    kristian> atanu at icsi.berkeley.edu> wrote:
    >>> >>>>>>> "Kristian" == Kristian Larsson
    sanjeev>      <kristian at spritelink.net>
    >>> >>>>>>> writes:
    >>> >>
    Kristian> Hansi wrote:
    >>> >> >> Hello All,
    >>> >> >>
    >>> >> >> I'm currently learning how to configure OSPFv2 on two
    sanjeev>      XORP
    >>> >> >> machines just to establish adjacency with one another.
    sanjeev>      In a
    >>> p2p >> >> link type, is it still necessary to explicitly set
    sanjeev>      the
    >>> >> 'neighbor' >> parameter of each machine before adjacency
    sanjeev>      is >>
    >>> established?  >> Furthermore, would it be possible to set
    sanjeev>      the >>
    >>> router-id to its >> loopback address? instead of say.. the
    sanjeev>      ip >>
    >>> address of the >> interface on which ospf will be used?
    >>> >>
    Kristian> The neighbor command is only useful if you are using
    sanjeev>      a
    Kristian> medium on which the routers cannot broadcast and thus
    Kristian> cannot discover each other.  If you're using ethernet
    Kristian> (which I presume from your NIC names) you do not have
    sanjeev>      to
    Kristian> use the neighbor statements. I would advice
    sanjeev>      configuring
    Kristian> the interfaces as link-type p2p as this avoids DR
    sanjeev>      election
    Kristian> and unnecessary CPU load.
    >>> >> I am fairly sure that it is necessary to use the
    sanjeev>      neighbour >>
    >>> statements.
    >>> 
    kristian> Are you serious?  I haven't used the XORP code in
    sanjeev>      quite
    kristian> some time now.. but at least I thought XORP
    sanjeev>      implemented
    kristian> the OSPF standard. AFAIK, that includes being able to
    kristian> discover neighbors and turn up adjacencies to them.
    sanjeev>      Is
    kristian> this not the case?  Observe that he is running an
    sanjeev>      Ethernet
    kristian> point-to-point link, ie, it is not a non-broadcast
    sanjeev>      medium.
    kristian> Or are you saying that you can't do link-type p2p
    sanjeev>      without
    kristian> configuring neighbours ?
    >>> If the link-type is set to "broadcast" then the neighbours
    sanjeev>      will
    >>> be correctly discovered. If the link-type is set to "p2p"
    >>> (Point-to-point) or "p2m" (Point-to-multipoint) then it is
    >>> necessary to configure the neighbours. It has been argued
    sanjeev>      that it
    >>> should not be necessary to configure the neighbours if the
    >>> routers are connected via a true Point-to-point link, but
    >>> unfortunately even in this case it is necessary to configure
    sanjeev>      the
    >>> neighbour.
    kristian> Okey, that "kinda" makes sense. I apparently forgot
    sanjeev>      or
    kristian> missed the conversation on this.  What I want to
    sanjeev>      configure
    kristian> with link-type p2p is not whether or not the router
    sanjeev>      should
    kristian> try to broadcast but if it should setup one of those
    kristian> virtual router thingys, hehe. I'm not very familiar
    sanjeev>      with
    kristian> the terminology but (as you know) on a broadcast
    sanjeev>      medium
    kristian> you first have a DR selection and all that and then
    sanjeev>      you're
    kristian> gonna run your SPF. Since SPF can't handle the
    sanjeev>      concept of
    kristian> a broadcast medium it creates a "virtual router" to
    kristian> represent the broadcast medium and connects all
    sanjeev>      routers in
    kristian> that broadcast domain as adjacencies to the virtual
    kristian> router.  When I configure 'isis network
    sanjeev>      point-to-point' on
    kristian> a Cisco router I expect it to not setup one of these
    kristian> "virtual routers" in it's SPF topology. And this is
    kristian> different with XORP?
    sanjeev>      Setting the link type to "broadcast" or "p2p" will
    sanjeev> both result in the hello packets being broadcast, the
    sanjeev> distinction is that if the link-type is set to "p2p" no DR
    sanjeev> election will be attempted. The XORP OSPF behaves as
    sanjeev> specified in the relevant RFCs and interoperates with other
    sanjeev> OSPF implementations, the only difference is in
    sanjeev> configuration of a "p2p" where we require the neighbour to
    sanjeev> be specified, which as I mentioned before should not
    sanjeev> strictly be necessary.  Atanu.
    sanjeev> ------------------------------ Message: 5 Date: Thu, 13 Sep
    sanjeev> 2007 23:51:06 +0200 From: <kristian at spritelink.net>
    sanjeev> Subject: Re: [Xorp-users] Questions on OSPF To:
    sanjeev> atanu at ICSI.Berkeley.EDU Cc: xorp <xorp-users at xorp.org>
    sanjeev> Message-ID: <
    sanjeev> 5f7ec0f76565b4e68ed2457fdf8df3b8 at Mail.SpriteLink.NET>
    sanjeev> Content-Type: text/plain; charset="UTF-8" On Thu, 13 Sep
    sanjeev> 2007 14:58:01 -0700, Atanu Ghosh <atanu at icsi.berkeley.edu >
    sanjeev> wrote:
    >>>>>>> "kristian" == kristian <kristian at spritelink.net> writes:
    >>
    kristian> On Thu, 13 Sep 2007 12:18:42 -0700, Atanu Ghosh
    kristian> <atanu at icsi.berkeley.edu> wrote:
    >> >>>>>>> "kristian" == kristian < kristian at spritelink.net>
    sanjeev>      writes:
    >> >>
    kristian> On Thu, 13 Sep 2007 11:51:32 -0700, Atanu Ghosh
    kristian> <atanu at icsi.berkeley.edu > wrote:
    >> >> >>>>>>> "Kristian" == Kristian Larsson
    sanjeev>      <kristian at spritelink.net>
    >> >> >>>>>>> writes:
    >> >> >>
    Kristian> Hansi wrote:
    >> >> >> >> Hello All,
    >> >> >> >>
    >> >> >> >> I'm currently learning how to configure OSPFv2 on
    sanjeev>      two XORP
    >> >> >> >> machines just to establish adjacency with one
    sanjeev>      another. In a
    >> >> p2p >> >> link type, is it still necessary to explicitly
    sanjeev>      set the
    >> >> >> 'neighbor' >> parameter of each machine before
    sanjeev>      adjacency is >>
    >> >> established?  >> Furthermore, would it be possible to set
    sanjeev>      the >>
    >> >> router-id to its >> loopback address? instead of say.. the
    sanjeev>      ip >>
    >> >> address of the >> interface on which ospf will be used?
    >> >> >>
    Kristian> The neighbor command is only useful if you are
    sanjeev>      using a
    Kristian> medium on which the routers cannot broadcast and
    sanjeev>      thus
    Kristian> cannot discover each other.  If you're using
    sanjeev>      ethernet
    Kristian> (which I presume from your NIC names) you do not
    sanjeev>      have to
    Kristian> use the neighbor statements. I would advice
    sanjeev>      configuring
    Kristian> the interfaces as link-type p2p as this avoids DR
    sanjeev>      election
    Kristian> and unnecessary CPU load.
    >> >> >> I am fairly sure that it is necessary to use the
    sanjeev>      neighbour >>
    >> >> statements.
    >> >>
    kristian> Are you serious?  I haven't used the XORP code in
    sanjeev>      quite
    kristian> some time now.. but at least I thought XORP
    sanjeev>      implemented
    kristian> the OSPF standard. AFAIK, that includes being able
    sanjeev>      to
    kristian> discover neighbors and turn up adjacencies to them.
    sanjeev>      Is
    kristian> this not the case?  Observe that he is running an
    sanjeev>      Ethernet
    kristian> point-to-point link, ie, it is not a non-broadcast
    sanjeev>      medium.
    kristian> Or are you saying that you can't do link-type p2p
    sanjeev>      without
    kristian> configuring neighbours ?
    >>  >> If the link-type is set to "broadcast" then the
    sanjeev>      neighbours will
    >> >> be correctly discovered. If the link-type is set to "p2p" >>
    >> (Point-to-point) or "p2m" (Point-to-multipoint) then it is >>
    >> necessary to configure the neighbours. It has been argued
    sanjeev>      that it
    >> >> should not be necessary to configure the neighbours if the >>
    >> routers are connected via a true Point-to-point link, but >>
    >> unfortunately even in this case it is necessary to
    sanjeev>      configure the
    >> >> neighbour.
    >> 
    kristian> Okey, that "kinda" makes sense. I apparently forgot
    sanjeev>      or
    kristian> missed the conversation on this.  What I want to
    sanjeev>      configure
    kristian> with link-type p2p is not whether or not the router
    sanjeev>      should
    kristian> try to broadcast but if it should setup one of
    sanjeev>      those
    kristian> virtual router thingys, hehe. I'm not very familiar
    sanjeev>      with
    kristian> the terminology but (as you know) on a broadcast
    sanjeev>      medium
    kristian> you first have a DR selection and all that and then
    sanjeev>      you're
    kristian> gonna run your SPF. Since SPF can't handle the
    sanjeev>      concept of
    kristian> a broadcast medium it creates a "virtual router" to
    kristian> represent the broadcast medium and connects all
    sanjeev>      routers in
    kristian> that broadcast domain as adjacencies to the virtual
    kristian> router.  When I configure 'isis network
    sanjeev>      point-to-point' on
    kristian> a Cisco router I expect it to not setup one of
    sanjeev>      these
    kristian> "virtual routers" in it's SPF topology. And this is
    kristian> different with XORP?
    >>  Setting the link type to "broadcast" or "p2p" will both result
    >> in
    sanjeev>      the
    >> hello packets being broadcast, the distinction is that if the
    sanjeev>      link-type
    >> is set to "p2p" no DR election will be attempted.
    sanjeev>      Alright, just as I expected.
    >> The XORP OSPF behaves as specified in the relevant RFCs and
    >> interoperates with other
    sanjeev>      OSPF
    >> implementations, the only difference is in configuration of a
    sanjeev>      "p2p"
    >> where we require the neighbour to be specified, which as I
    sanjeev>      mentioned
    >> before should not strictly be necessary.
    sanjeev>      Okey, not what I expected. Why is it so? Just lack of
    sanjeev> time to do the actual implementation (although I don't see
    sanjeev> how it would actually be more code than it is today) or has
    sanjeev> there been a policy decision against it?  -K
    sanjeev> ------------------------------ Message: 6 Date: Thu, 13 Sep
    sanjeev> 2007 16:11:57 -0700 From: Pavlin Radoslavov
    sanjeev> <pavlin at icir.org> Subject: Re: [Xorp-users] Unreachable
    sanjeev> default route.  To: Ben Greear <greearb at candelatech.com>
    sanjeev> Cc: xorp-users at xorp.org, Pavlin Radoslavov <pavlin at icir.org
    sanjeev> >, Tim Durack <tdurack at gmail.com> Message-ID:
    sanjeev> <200709132312.l8DNBvsa040733 at possum.icir.org > Ben Greear
    sanjeev> <greearb at candelatech.com> wrote:
    >> Pavlin Radoslavov wrote:
    >> 
    >> > You could use the following configuration on Linux to configure
    sanjeev>      a
    >> > discard interface and a static route that is blackhole:
    >> >
    >> > interfaces { > interface my_discard { > discard: true > vif
    >> my_discard { > } > } > }
    >> 
    >> [snip]
    >> 
    >> Ok, this does indeed create a blackhole route.  But, it seems
    sanjeev>      this will just
    >> silently eat packets.  What I really want is unreachable, which
    sanjeev>      will return ~~~~~~~~~~~~~~~~~~~~ Correct. This is the
    sanjeev> definition of "blackhole" :)
    >> the proper ICMP packet saying the destination is unreachable.
    >> 
    >> Any idea how hard it would be to add this functionality?
    sanjeev>      You need to install a different type of route in the
    sanjeev> kernel which I believe in Linux is RTN_UNREACHABLE instead
    sanjeev> of RTN_BLACKHOLE.  However, XORP doesn't support such
    sanjeev> routes.  You could try experimenting with such routes by
    sanjeev> replacing all references (I counted two references) of
    sanjeev> RTN_BLACKHOLE with RTN_UNREACHABLE inside file
    sanjeev> fea/data_plane/fibconfig/fibconfig_entry_set_netlink_socket.cc
    sanjeev> This is not the right solution, but allows you to play with
    sanjeev> such routes.  Just curious, could you describe your
    sanjeev> particular scenario you have that requires installing
    sanjeev> RTN_UNREACHABLE routes.
    >> In the meantime, I'll work on a patch that makes the 'static'
    sanjeev>      priority
    >> configurable with an environment variable.
    sanjeev>      I should tell you upfront that configurable admin
    sanjeev> distances in RIB has been on our TODO list for quite some
    sanjeev> time. However it is not trivial if we want to do it
    sanjeev> properly by taking into account various considerations.
    sanjeev> E.g., one of the goals is to be able to configure the
    sanjeev> priorities (on the fly) inside the XORP config file.
    sanjeev> Hence, most likely we won't use a solution that is based on
    sanjeev> setting an environmental variable (or something like this).
    sanjeev> In other words, don't be offended if your patch is not
    sanjeev> applied to the CVS.  Though, if I were in your position I
    sanjeev> would use such shortcut in my local XORP copy.  Regards,
    sanjeev> Pavlin
    >> Thanks, Ben
    >> 
    >> --
    >> Ben Greear <greearb at candelatech.com> Candela Technologies Inc
    >> http://www.candelatech.com
    >> 
    >> _______________________________________________ Xorp-users
    >> mailing list Xorp-users at xorp.org
    >> http://mailman.ICSI.Berkeley.EDU/mailman/listinfo/xorp-users
    sanjeev>      ------------------------------
    sanjeev> _______________________________________________ Xorp-users
    sanjeev> mailing list Xorp-users at xorp.org
    sanjeev> http://mailman.ICSI.Berkeley.EDU/mailman/listinfo/xorp-users
    sanjeev> End of Xorp-users Digest, Vol 18, Issue 15
    sanjeev> ******************************************

    sanjeev>    -- Efforts may fail,But don't Fail to make efforts.
    sanjeev> --------- Sanjeev Kumar Project Engineer CDAC(Formerly
    sanjeev> NCST) Juhu,Mumbai-400049
    sanjeev> _______________________________________________ Xorp-users
    sanjeev> mailing list Xorp-users at xorp.org
    sanjeev> http://mailman.ICSI.Berkeley.EDU/mailman/listinfo/xorp-users



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