NAT bypass verification

To verify that NAT bypass is in effect, use the following show service active-subscribers detail and show filter ip commands.

*A:Dut-C# show service active-subscribers detail 
===============================================================================
Active Subscribers
===============================================================================
-------------------------------------------------------------------------------
Subscriber AL_x0ffx6x0x0x2
           (sub_l2-dhcp1)
-------------------------------------------------------------------------------
NAT Policy    : pol-B-1
Outside IP    : 130.0.0.201
Ports         : 1536-1570
NAT Policy    : pol-o-1
Outside IP    : 19.0.0.87 (vprn101)
Ports         : 1024-1055
NAT Policy    : pol-o1-1
Outside IP    : 130.0.0.68 (vprn601)
Ports         : 1152-1349
NAT Policy    : pol-o2-1
Outside IP    : 130.0.0.222 (vprn602)
Ports         : 1152-1349
-------------------------------------------------------------------------------
I. Sched. Policy : N/A                              
E. Sched. Policy : N/A                              E. Agg Rate Limit: Max
                                                    E. Min Resv Bw   : 1
I. Policer Ctrl. : N/A                              
E. Policer Ctrl. : N/A                              
I. vport-hashing : Disabled                         
I. sec-sh-hashing: Disabled                         
Q Frame-Based Ac*: Disabled                         
Acct. Policy     : N/A                              Collect Stats    : Disabled
ANCP Pol.        : N/A                              
Accu-stats-pol   : (Not Specified)                  
HostTrk Pol.     : N/A                              
IGMP Policy      : N/A                              
MLD Policy       : N/A                              
PIM Policy       : N/A                              
Sub. MCAC Policy : N/A                              
NAT Policy       : pol-o-1                          
Firewall Policy  : N/A                              
UPnP Policy      : N/A                              
NAT Prefix List  : npl-4                            
Allow NAT bypass : Yes

This command shows that the ESM subscriber is a L2-Aware NAT subscriber for which bypass is enabled.

The following command provides insight into whether the NAT bypass is in effect:

*A:Dut-A>config>filter# show filter ip 10
===============================================================================
IP Filter
===============================================================================
Filter Id           : 10                           Applied        : Yes
Scope               : Template                     Def. Action    : Drop
Type                : Normal
System filter       : Unchained
Radius Ins Pt       : n/a
CrCtl. Ins Pt       : n/a
RadSh. Ins Pt       : n/a
PccRl. Ins Pt       : n/a
Entries             : 1
Description         : (Not Specified)
Filter Name         : 10
-------------------------------------------------------------------------------
Filter Match Criteria : IP
-------------------------------------------------------------------------------
Entry               : 1
Description         : (Not Specified)
Log Id              : n/a
Src. IP             : 0.0.0.0/0
Src. Port           : n/a
Dest. IP            : 0.0.0.0/0
Dest. Port          : n/a
Protocol            : Undefined                    Dscp           : Undefined
ICMP Type           : Undefined                    ICMP Code      : Undefined
Fragment            : Off                          Src Route Opt  : Off
Sampling            : Off                          Int. Sampling  : On
IP-Option           : 0/0                          Multiple Option: Off
Tcp-flag            : (Not Specified)
Option-pres         : Off
Egress PBR          : Disabled
Primary Action      : Forward
L2 Aware NAT Bypass : Enabled
Ing. Matches        : 0 pkts
Egr. Matches        : 0 pkts
===============================================================================