[c-nsp] NAT problem on ISR 4331

David Prall dcp at dcptech.com
Mon Mar 21 21:45:15 EDT 2016


NVI isn’t supported within XE as you’ve stated. Have you tested with match-in-vrf on the ip nat command. 
http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipaddr_nat/configuration/xe-2/nat-xe-2-book/iadnat-match-vrf.html

As well your pool does not include the VRF that the pool belongs to. 

David

--
http://dcp.dcptech.com







On 3/16/16, 7:16 AM, "cisco-nsp on behalf of Eugen Şerban" <cisco-nsp-bounces at puck.nether.net on behalf of eugen.shr at gmail.com> wrote:

>Hello,
>
>I tried to implement the NVI, but according to cisco: NAT Virtual
>Interfaces (NVIs) are not supported in the Cisco IOS XE software.
>
>I cannot put the guest and the internet in the same VRF. As you can see
>from the routing tables, the default route for both guest and hotspot is in
>a separate tunnel (400 for guest and 600 for hotspot). If I put them in the
>internet VRF I'd have to implement PBR, which I don't.
>
>From your configuration, I can see that you also have the internet in a
>different VRF (not the global).
>
>Just to recap, everything works if I create the nat per interface, but it
>doesn't work if the nat is per pool.
>
>This works:
>ip nat inside source list Guest2Internet interface gi 0/0/2 vrf guest
>overload
>
>This does not work:
>ip nat pool GuestNAT 1.2.3.91 1.2.3.91 netmask 255.255.255.248
>ip nat inside source list Guest2Internet pool GuestNAT vrf guest overload
>
>
>2016-03-16 11:54 GMT+01:00 Nick Cutting <ncutting at edgetg.co.uk>:
>
>> Sorry Global table... not global vrf
>>
>> Also - you may get more options using the NVI rather than ip nat inside /
>> outside when the internet is in a vrf - but less when the internet is in
>> the global table is involved.  I cannot remember the specifics - but stick
>> to this rule.
>>
>> This is on a router with ADSL default route in a VRF, and the guest wifi
>> in the same VRF
>>
>> interface GigabitEthernet0/0.201
>>  ip nat enable
>>
>> ip nat source list GUEST-WIFI-NAT interface GigabitEthernet0/0.201 vrf
>> ADSL overload
>>
>>
>>
>> -----Original Message-----
>> From: cisco-nsp [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of
>> Nick Cutting
>> Sent: 16 March 2016 10:37
>> To: Eugen Şerban; cnsp at marenda.net
>> Cc: cisco-nsp at puck.nether.net
>> Subject: Re: [c-nsp] NAT problem on ISR 4331
>>
>> These routers are much closer to ASR than ISR - they have the same feature
>> set. - e.g. VASI interfaces etc.
>>
>> Juergen is right about the global VRF - that is where I keep the internet
>> (default route), when implementing similar designs
>>
>> -----Original Message-----
>> From: cisco-nsp [mailto:cisco-nsp-bounces at puck.nether.net] On Behalf Of
>> Eugen Serban
>> Sent: 16 March 2016 09:36
>> To: cnsp at marenda.net
>> Cc: cisco-nsp at puck.nether.net
>> Subject: Re: [c-nsp] NAT problem on ISR 4331
>>
>> Hello Juergen,
>>
>> Please find bellow the routing table for all VRFs.
>>
>> The idea with this router is that in the future it might be used for
>> "hybrid networks", "local internet breakout" (or however you'd like to call
>> it). So we plan to use the default VRF for internal (trusted) traffic.
>>
>> hostname#sh ip route
>> [...]
>>
>> Gateway of last resort is not set
>>
>>       192.168.0.0/16 is variably subnetted, 3 subnets, 3 masks
>> S        192.168.0.0/16 [1/0] via 192.168.37.1
>> C        192.168.37.0/26 is directly connected, GigabitEthernet0/0/1.1
>> L        192.168.37.56/32 is directly connected, GigabitEthernet0/0/1.1
>>
>> hostname#sh ip route vrf internet
>>
>> Routing Table: internet
>> [...]
>>
>> Gateway of last resort is 1.2.3.89 to network 0.0.0.0
>>
>> S*    0.0.0.0/0 [1/0] via 1.2.3.89, GigabitEthernet0/0/2
>>       1.0.0.0/8 is variably subnetted, 4 subnets, 2 masks
>> C        1.2.3.88/29 is directly connected, GigabitEthernet0/0/2
>> L        1.2.3.90/32 is directly connected, GigabitEthernet0/0/2
>> L        1.2.3.91/32 is directly connected, GigabitEthernet0/0/2
>> L        1.2.3.92/32 is directly connected, GigabitEthernet0/0/2
>>       14.0.0.0/32 is subnetted, 1 subnets
>> S        14.22.77.29 [1/0] via 1.2.3.89, GigabitEthernet0/0/2
>>       18.0.0.0/32 is subnetted, 1 subnets
>> S        18.33.25.41 [1/0] via 1.2.3.89, GigabitEthernet0/0/2
>>
>> hostname#sh ip route vrf guest
>>
>> Routing Table: guest
>> [...]
>>
>> Gateway of last resort is 0.0.0.0 to network 0.0.0.0
>>
>> S*    0.0.0.0/0 is directly connected, Tunnel400
>>       14.0.0.0/32 is subnetted, 1 subnets
>> B        14.22.77.29
>>            [20/0] via 1.2.3.89 (internet), 6d22h, GigabitEthernet0/0/2
>>       18.0.0.0/32 is subnetted, 1 subnets
>> B        18.33.25.41
>>            [20/0] via 1.2.3.89 (internet), 6d22h, GigabitEthernet0/0/2
>>       172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
>> C        172.16.112.0/23 is directly connected, GigabitEthernet0/0/1.122
>> L        172.16.112.1/32 is directly connected, GigabitEthernet0/0/1.122
>>
>>
>> hostname#sh ip route vrf hotspot
>>
>> Routing Table: hotspot
>> [...]
>>
>> Gateway of last resort is 0.0.0.0 to network 0.0.0.0
>>
>> S*    0.0.0.0/0 is directly connected, Tunnel600
>>       14.0.0.0/32 is subnetted, 1 subnets
>> B        14.22.77.29
>>            [20/0] via 1.2.3.89 (internet), 6d22h, GigabitEthernet0/0/2
>>       18.0.0.0/32 is subnetted, 1 subnets
>> B        18.33.25.41
>>            [20/0] via 1.2.3.89 (internet), 6d22h, GigabitEthernet0/0/2
>>       172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
>> C        172.16.32.0/23 is directly connected, GigabitEthernet0/0/1.121
>> L        172.16.32.1/32 is directly connected, GigabitEthernet0/0/1.121
>>
>>
>>
>> 2016-03-15 19:58 GMT+01:00 Juergen Marenda <cnsp at marenda.net>:
>>
>> > Hi,
>> >
>> > First of all, your routing statements would be from interest...
>> > For All mentioned VRFs and global, please.
>> >
>> > From my experience eith ISR1 Routers,
>> > "surf" nat outside interface almost always had to be the global vrf,
>> > not "vrf internet" ; and you must pin the inside vrf's (default-)route
>> > to the global (default-)gateway.
>> > (here, host-routes to your two special's should be sufficient)
>> >
>> > Finally I would tend to write " no ip virtual-reassembly " on nearly
>> > every Interface to disable that miss-feature.
>> >
>> > Hope this help's,
>> >
>> > Juergen.
>> >
>> > -----Ursprüngliche Nachricht-----
>> > Von: cisco-nsp [mailto:cisco-nsp-bounces at puck.nether.net] Im Auftrag
>> > von Eugen Serban
>> > Gesendet: Dienstag, 15. März 2016 16:23
>> > An: Nick Cutting
>> > Cc: cisco-nsp at puck.nether.net
>> > Betreff: Re: [c-nsp] NAT problem on ISR 4331
>> >
>> > Hello Nick,
>> >
>> > Thank you for the hint with monitor capture. I will try that one.
>> >
>> > to answer your questions, yes, it's because I need to present a
>> > different IP for each VRF.
>> >
>> > I am trying to use two different IPs for the NAT (we pay for them, so
>> > we might just use them), please see the conf.
>> >
>> >
>> > ip nat translation timeout 60
>> > ip nat translation tcp-timeout 60
>> > ip nat translation udp-timeout 60
>> > ip nat translation dns-timeout 60
>> > no ip nat service all-algs
>> > no ip nat service dns-reset-ttl
>> > !
>> > ip nat pool HotspotNAT 1.2.3.92 1.2.3.92 netmask 255.255.255.248 ip
>> > nat pool GuestNAT 1.2.3.91 1.2.3.91 netmask 255.255.255.248 !
>> > ip nat inside source list Guest2Internet pool GuestNAT vrf guest
>> > overload ip nat inside source list Hotspot2Internet pool HotspotNAT
>> > vrf hotspot overload !
>> > ip access-list extended Guest2Internet  permit ip 172.16.112.0
>> > 0.0.1.255 host 14.22.77.29  permit ip 172.16.112.0 0.0.1.255 host
>> > 18.33.25.41 ip access-list extended Hotspot2Internet
>> >   permit ip 172.16.32.0 0.0.1.255 host 14.22.77.29
>> >   permit ip 172.16.32.0 0.0.1.255 host 18.33.25.41 !
>> > interface GigabitEthernet0/0/1.121
>> >  description Hotspot Vlan
>> >  encapsulation dot1Q 121
>> >  ip vrf forwarding hotspot
>> >  ip address 172.16.32.1 255.255.254.0
>> >  ip nat inside
>> >  no cdp enable
>> >  arp timeout 300
>> >  ip virtual-reassembly
>> > !
>> > interface GigabitEthernet0/0/1.122
>> >  description Guest Vlan
>> >  encapsulation dot1Q 122
>> >  ip vrf forwarding guest
>> >  ip address 172.16.112.1 255.255.254.0  ip nat inside  no cdp enable
>> > arp timeout 300  ip virtual-reassembly !
>> > interface GigabitEthernet0/0/2
>> >  description WAN interface 1
>> >  ip vrf forwarding internet
>> >  ip address 1.2.3.91 255.255.255.248 secondary  ip address 1.2.3.92
>> > 255.255.255.248 secondary  ip address 1.2.3.90 255.255.255.248  no ip
>> > redirects  no ip unreachables  no ip proxy-arp  ip nat outside  ip
>> > verify unicast reverse-path 100  negotiation auto  no cdp enable  arp
>> > timeout 300  ip virtual-reassembly !
>> > [...]
>> >
>> >
>> _______________________________________________
>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>> _______________________________________________
>> cisco-nsp mailing list  cisco-nsp at puck.nether.net
>> https://puck.nether.net/mailman/listinfo/cisco-nsp
>> archive at http://puck.nether.net/pipermail/cisco-nsp/
>>
>_______________________________________________
>cisco-nsp mailing list  cisco-nsp at puck.nether.net
>https://puck.nether.net/mailman/listinfo/cisco-nsp
>archive at http://puck.nether.net/pipermail/cisco-nsp/



More information about the cisco-nsp mailing list