[j-nsp] NAT

[Kevin Oberman]

> From: Ibariouen Khalid <ibariouen.khalid at ericsson.com>
> Date: Fri, 26 Mar 2010 22:36:39 +0100
> Sender: juniper-nsp-bounces at puck.nether.net
> 
> Hi all
> Can someone tell me what does "no nat vector means" exactelly :
> 
> 
> GFW01(M)-> get counter statistics interface ethernet1/3
> Hardware counters for interface ethernet1/3:
> in bytes       201903417 | out bytes     2103176764 | early frame           0
> in packets    2949387186 | out packets   2468188341 | late frame            0
> in no buffer           0 | out no buffer          0 | re-xmt limit          0
> in overrun            63 | out underrun           0 | drop vlan             0
> address spoof          0 | in icmp        164486382 | no nat vector      1977
> 
> 
> in some document No nat vector Indicates the number of packets dropped
> because the Network Address Translation (NAT) connection was
> unavailable for the gate.
> 
> 
> But it's not clear for me ?  4 Public ip addresses are enought for
> 61973 sessions .

I believe it may be a count of packets received for which the router has
no NAT translation. I believe that this is a packet that the router
has no NAT translation to send it to. E.g. A packet arrives from a
when no outgoing traffic has established a destination nor is there a
pre-configured destination, The router has no place to forward the
packet, do it is counted and dropped.

A wide assortment of common network scans would result in this event.
-- 
R. Kevin Oberman, Network Engineer
Energy Sciences Network (ESnet)
Ernest O. Lawrence Berkeley National Laboratory (Berkeley Lab)
E-mail: oberman at es.net			Phone: +1 510 486-8634
Key fingerprint:059B 2DDF 031C 9BA3 14A4  EADA 927D EBB3 987B 3751