Hello there,
I believe someone from Internet could be probing Your address block including 
network and broadcast IP addresses on frame-relay link. Hence unnecessary 
"resolutions" are throttled and event logged.
Is it possible to change the /30 to /31? Same for IPv6, I'd suggest to try /126.
If not then I'd suggest to block traffic from Internet to Your /30 with FW 
filter unless there is a legitimate reason for Internet users to access these 
IPs.
Regards
Alex
  ----- Original Message ----- 
  From: juni...@iber-x.com 
  To: Alex ; juniper-nsp@puck.nether.net 
  Sent: Tuesday, May 18, 2010 4:43 PM
  Subject: Re: [j-nsp] ssb NH: resolutions from x throttled


  Hi,

  Regardings your questions,

  1.- The encapsulation in these interfaces is frame-relay.

  2.- Addresses are public and we don't advertise this /30  link to the 
Internet only the general range of IP.

  3.- There isn't the same IPs in other interfaces. 
  The configuration of this particular interface is:

  lt-0/2/0 {
                  unit 101 {
                      encapsulation frame-relay;
                      dlci 100;
                      peer-unit 100;
                      family inet {
                          no-redirects;
                          address x/30;
                      }
                      family iso;
                      family inet6 {
                          y/124;
                          z/64;
                      }
                      family mpls;
                  }
  }

  Thanks for your time,



  El 17/05/2010 20:32, Alex escribió: 
    Hello there,
    May I ask some questions please?
    1/ What is the encapsulation on this link?
    2/ What are the link IP addresses: public or private? If public do you 
advertise these link addresses to the Internet at large?
    3/ Do these addresses overlap with addresses somewhere else in Your 
network? Perhaps in VRF?
    Regards
    Alex

      ----- Original Message ----- 
      From: juni...@iber-x.com 
      To: Alex ; juniper-nsp@puck.nether.net 
      Sent: Monday, May 17, 2010 4:25 PM
      Subject: Re: [j-nsp] ssb NH: resolutions from x throttled


      Hi,

      Our router M20 is divided in two logical routers, one is the physical and 
the other is the logical. And it is in the logical tunnel interface, lt-0/2/0, 
where the problem are. And it is only in that two interfaces where we've 
thought to apply the statement: 'proxy-arp'. What is it your opinion about the 
implementation in this scenario? 

      Do you have any other idea to solve this message in our Juniper's log 
without make a JUNO's upgrade? I would appreciate it because we are trying to 
solve it for a long time without success.

      Thanks,


      El 17/05/2010 11:16, Alex escribió: 
        I am sure You realise "proxy-arp" is an ARP Response function: 

        Warning: If you configure unrestricted proxy ARP, the proxy router 
replies to ARP requests for the target IP address on the same interface as the 
incoming ARP request. 
        
http://www.juniper.net/techpubs/software/junos/junos90/swconfig-network-interfaces/configuring-unrestricted-proxy-arp.html
 

        So if You have another JUNOS box sitting on the same PE-CE subnet with 
M20, and M20 has traffic coming in from its core-facing interface and addressed 
to unassigned IP addresses on said subnet, You can always configure "proxy-arp" 
on that other JUNOS box in order to respond to M20 and keep poor old M20 
happy... 

        Cheers 
        Alex 

        ----- Original Message ----- From: <juni...@iber-x.com> 
        To: "Christoph Blecker" <ad...@toph.ca>; <juniper-nsp@puck.nether.net> 
        Sent: Monday, May 17, 2010 10:45 AM 
        Subject: Re: [j-nsp] ssb NH: resolutions from x throttled 


        Hello, 

        Yes, we had read this upgrade recomendation but we are looking for an 
        alternative solution. How I said, we read that there is a possibility 
to 
        set a 'proxy-arp' option for a particular interface 
        
(http://www.juniper.net/techpubs/software/junos/junos90/swconfig-network-interfaces/configuring-unrestricted-proxy-arp.html)
 
        and maybe it exists a statement for the opposite because we think that 
        perhaps it will solve the 'problem'. 

        Set this statement is only one idea (probably it doesn't work) but, 
does 
        anyone have another idea? 

        Thanks for your help and time, 


        El 17/05/2010 10:18, Christoph Blecker escribió: 

          -----BEGIN PGP SIGNED MESSAGE----- 
          Hash: SHA1 

          Hello, 
          The issue appears to be a bug in the JUNOS version you are running. A 
          quick Google search turned up the following: 

          
http://www.juniper.net/techpubs/software/junos/junos73/rn-sw-73/previous-releases.html
 

          "If a router receives rapid multicast traffic from various groups or 
          sources that do not have entries in the forwarding table, the router 
          might generate the ?router-name feb NH: resolutions from iif number 
          throttled? system log message and might delay the installation of 
          forwarding table entries for some of these multicast packets. 
[PR/46474: 
          This issue has been resolved.]" 

          Solution would be to review your hardware and upgrade your JUNOS 
version 
          as applicable. ARP resolution is a normal and necessary funtion of 
the 
          router, and you would not want to disable it (I'm not even sure there 
          *is* a way to disable it withing JUNOS). 

          Cheers, 
          - -Christoph 

          On 10-05-17 01:43 AM, juni...@iber-x.com wrote: 


            Hi there, 

            We have a Juniper M20 with JUNOS 7.3R1.4, old version :( .. and 
since 
            few we have in our log these entries: 

            May 10 23:49:48.177 2010  xxxxx ssb NH: resolutions from iif 73 
throttled 
            May 10 23:50:41.168 2010  xxxxx ssb NH: resolutions from iif 88 
throttled 
            .. 

            Someone told us that maybe was a  port/ip scan on an Ethernet 
subnet and 
            this causes a flood of ARP requests. 
            We found that there is a statement to set the 'proxy-arp' option: 

            [edit] 
            u...@host# set interfaces interface-name unit logical-unit-number 
proxy-arp 

            But we can't find the opposite statement, I mean that the router 
doesn't 
            register any arp resolution in one interface. 

            Also we read that it was a problem [PR/46474] solved since the 
version 
            7.3R3 but we have an older JUNOS version.. 

            Does anyone know how to solve this 'problem'? 

            Thanks in advance, 



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