can you paste config from BB1 and it's RIB?

2012/3/16 Imre Oszkar <[email protected]>

>
> Hi Piotr,
>
> Thanks for the idea! Seems that it should work, but for some reason I
> cannot see any OOO packet.
>
> I set up the following scenario:
> 1.  unequal path between the source (BB1) and the destination (server).
> BB1 is doing per-packet load balancing.
> 2.  Outbound rate limiter on R4
>
>
>
>                |----R4---R1----\
> |BB1|----|                         -----R3----R5---|SERVER|
>                |-----------R2----/
>
>
> Per packet load-balaning:
>
> BB1#traceroute 136.1.122.100 (Server)
>
> Type escape sequence to abort.
> Tracing the route to 136.1.122.100
>
>   1 10.5.8.2 4 msec
>     10.5.8.4 0 msec
>     10.5.8.2 4 msec
>   2 10.5.9.1 0 msec
>     10.5.11.3 4 msec
>     10.5.9.1 0 msec
>   3 136.1.121.5 4 msec
>     10.5.10.3 0 msec
>     136.1.121.5 0 msec
>   4 136.1.121.5 4 msec
>     136.1.122.100 0 msec
>     136.1.121.5 0 msec
>
>
> On R4 I have outbound rate-limiter which is heavily dropping packets.
>
> R4#sh interfaces rate-limit
> FastEthernet0/0
>   Output
>     matches: all traffic
>       params:  8000 bps, 1500 limit, 2000 extended limit
>       conformed 1286 packets, 72962 bytes; action: transmit
>       exceeded 12008 packets, 649782 bytes; action: drop
>       last packet: 1680ms ago, current burst: 0 bytes
>       last cleared 00:11:14 ago, conformed 0 bps, exceeded 7000 bps
>
>
> I'm doing FTP file transfer between the Server and BB1 and I'm running
> wireshark on the Server. Wireshark doesn't report a single OOO
> packet. There is nothing enabled on the routers between BB1 and Server that
> would cause packet reassembling.
>
> Do I miss something here? Can you help me out?
>
> Thanks,
> Oszkar
>
>
> On Wed, Mar 14, 2012 at 10:08 AM, Piotr Matusiak <[email protected]> wrote:
>
>> Hi,
>>
>> CBAC does reassembly for all packets not only those subjected to DPI. I'm
>> not sure about packet copy tho.
>> For ZBF you must have at least 15.0 to make OOO packets work. It does not
>> work for 12.4T.
>>
>> You can generate OOO packets by trying to setup unequal path to the
>> destination and involve some rate-limiting on one leg. Then configure CEF
>> per-packet load balancing and you'll see packets going through two paths
>> being OOO at the destination.
>>
>> Regards,
>> Piotr
>>
>>
>> 2012/3/14 Imre Oszkar <[email protected]>
>>
>>> Hi Kings,
>>>
>>> I'm familiar with that output, but that doesn't really answer any of my
>>> questions.
>>>
>>> CBAC:
>>> 1. is it true that  OOO reassembly works only for packets that requires
>>> application inspection (DPI). If no appfw is configured OOO packets are
>>> dropped.
>>> 2. is it true that the packets reaching the destination will be  still
>>> OOO. (so all the reordering happens on a copy of the packet not the
>>> original packet)
>>>
>>> ZBF:
>>> 1. in case of ZBF  is it enough to configure L4 inspection (match
>>> protocol TCP) in order to kick in the reassembly for the OOO packets?
>>>
>>> Nothing comes in my mind how can I generate OOO packets in a lab
>>> environment to test all these, so if somebody could give me an idea that
>>> would be wonderful.
>>>
>>> Thanks,
>>> Oszkar
>>>
>>>
>>> On Wed, Mar 14, 2012 at 1:24 AM, Kingsley Charles <
>>> [email protected]> wrote:
>>>
>>>> By default, CBAC support OoO. check out the following snippet.
>>>>
>>>> router#sh ip inspect all
>>>> Dropped packet logging is enabled
>>>> Session audit trail is disabled
>>>> Session alert is enabled
>>>> one-minute (sampling period) thresholds are [unlimited : unlimited]
>>>> connections
>>>> max-incomplete sessions thresholds are [unlimited : unlimited]
>>>> max-incomplete tcp connections per host is unlimited. Block-time 0
>>>> minute.
>>>> tcp synwait-time is 30 sec -- tcp finwait-time is 5 sec
>>>> tcp idle-time is 3600 sec -- udp idle-time is 30 sec
>>>> *tcp reassembly queue length 16; timeout 5 sec; memory-limit 1024 kilo
>>>> bytes*
>>>>
>>>> In 12.4(15)T, ZFW doesn't have the parameter map to configure OoO. And
>>>> I guess, it supports it.
>>>>
>>>> With regards
>>>> Kings
>>>>
>>>> On Tue, Mar 13, 2012 at 11:02 AM, Imre Oszkar <[email protected]>wrote:
>>>>
>>>>> Hi guys,
>>>>>
>>>>> Does anybody have a clear understanding of how OOO packets are handled
>>>>> by the IOS firewall (CBAC and ZBF)?
>>>>> I have found a lot of contradictory information  about this topic on
>>>>> the cisco site,  and I'm getting confused.
>>>>>
>>>>> CBAC
>>>>>
>>>>> According to my understanding in case of CBAC OOO packets are dropped
>>>>> by default. However if we configure L7 inspection for a certain protocol
>>>>> then OOO packet support kicks in for that particular protocol. That means
>>>>> that a copy of the out-of-order packets will be copied into the buffer
>>>>> while the original packet will be transmitted to the destination as it is.
>>>>> No reordering. Once the missing sequence arrives the firewall will fill 
>>>>> the
>>>>> hole and will do  the firewall logic and the result will be a new session.
>>>>>
>>>>> With the  "ip inspect tcp reassembly queue lenght 0" I can disable the
>>>>> OOO packet processing. So even the L7 inspected packets are going to be
>>>>> dropped if they are OOO.
>>>>>
>>>>>
>>>>> Zone based firewall
>>>>>
>>>>> "OoO packets are dropped when IPS and zone-based policy firewall with
>>>>> L4 inspection are enabled."
>>>>> According to this sentence OOO are treated in the same way as in case
>>>>> of CBAC, however the same config guide later on says:
>>>>>
>>>>> "In Cisco IOS Release 12.4(15)T, OoO processing was enabled for
>>>>> zone-based firewall and for IPS shared sessions with Layer 4 match (match
>>>>> protocol TCP, match protocol http), and for any TCP-based Layer 7 packet
>>>>> ordering."
>>>>> From this one I understand that OOO processing works for L4 inspected
>>>>> packets as well eg for any TCP traffic.
>>>>>
>>>>>
>>>>> http://www.cisco.com/en/US/docs/ios-xml/ios/sec_data_zbf/configuration/12-4t/sec-zone-pol-fw.html#GUID-CA37F2B4-CA9D-44DD-9B27-C9C235C4D4DE
>>>>>
>>>>>
>>>>>
>>>>> Thank you for your comments!
>>>>> Oszkar
>>>>>
>>>>> _______________________________________________
>>>>> For more information regarding industry leading CCIE Lab training,
>>>>> please visit www.ipexpert.com
>>>>>
>>>>> Are you a CCNP or CCIE and looking for a job? Check out
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>>>>>
>>>>
>>>>
>>>
>>> _______________________________________________
>>> For more information regarding industry leading CCIE Lab training,
>>> please visit www.ipexpert.com
>>>
>>> Are you a CCNP or CCIE and looking for a job? Check out
>>> www.PlatinumPlacement.com
>>>
>>
>>
>
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