Re: GNS ICMP drops to real switches

You try swapping out the NICs? Are you using USB to Ethernet adapters or a
breakout switch? I actually set my adapters to accept Jumbo Frames and that
solved a lot of issues for me (1500 > 2000 bytes).

On Wed, Aug 15, 2012 at 9:26 AM, Maarten Vervoorn <mr.vervoorn_at_gmail.com>wrote:

> I have did some more troubleshooting and it seems that when I send only
> 40byte icmp packets I will no drops. When I send ICMP packets of 41 bytes I
> do receive drops
>
> Regards,
>
> Maarten
>
> 2012/8/15 Maarten Vervoorn <mr.vervoorn_at_gmail.com>
>
>> Stephen,
>>
>> All protocols work fine. The packets are leaving the virtual network
>> because I can see it in wireshark. This probably means something is wrong
>> with the NIC. Could be hardware or some driver settings
>>
>> I also used GNS during my CCIE study everything works perfectly no ping
>> drops there. I would not relate this issue to GNS or dynamibs but to some
>> NIC settings. Currently I'm building a CCIE lab for some collegues who are
>> also studying for the CCIE exam. I was wondering someone maybe had the same
>> issue and was able to solve it.
>>
>> Kind regards,
>>
>> Maarten Vervoorn
>>
>> 2012/8/15 Stephen Lynch <slynch_at_absnt.com>
>>
>>> I know this is probably not something you want to hear, but I used GNS3
>>> throughout my entire study process and somethings simply don't work.
>>> Multicast and NTP are technologies that don't really play well with GNS3
>>> and you may get varied results from lab to lab.
>>>
>>> Stephen Lynch
>>> CCIE #36243
>>>
>>>
>>>
>>>
>>> On Wed, Aug 15, 2012 at 9:06 AM, Maarten Vervoorn <
>>> mr.vervoorn_at_gmail.com> wrote:
>>>
>>>> It is ping with any number from a 7200 router. If I send 1000 or 5000
>>>> pings
>>>> 5% is dropped. Size is 100bytes.
>>>>
>>>> Host link is 100Mbps. No error and collisions are in the statistics of
>>>> the
>>>> adapter, virtual router, breakout switch or physical switch.
>>>> The physical host link is shared among 9 virtual routers with 12
>>>> ethernet
>>>> connections over that. The NIC creates an adapter for each VLAN which is
>>>> attached to one ethernet link of the virtual router and not shared with
>>>> other connections. Behind the physcial port is a breakout switch which
>>>> uses
>>>> QinQ tunneling.
>>>> I have also tested the configuration without QinQ and just attached one
>>>> router to the breakout switch and have routed ports on both sites. So a
>>>> direct L3 connection between physical and virtual and gave the same
>>>> result.
>>>> I can see the packet in Wireshark leaving the server. That is just
>>>> before
>>>> the data is actually set on the NIC. But I do not receive it on the
>>>> switch
>>>> behind it. So it seems on the transmit site of the NIC it gets dropped
>>>>
>>>> Kind regards,
>>>>
>>>> Maarten Vervoorn
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> 2012/8/15 Carlos G Mendioroz <tron_at_huapi.ba.ar>
>>>>
>>>> > What kind of pings give you drops ? (I.e. size, frequency)
>>>> > Is this repeatable ?
>>>> >
>>>> > May be you are getting a collision where it is not expected?
>>>> > Your host link is @100Mbps ? @ Giga ?
>>>> >
>>>> > Is your host link dedicated to just this virtual trunk ? Can you
>>>> check tx
>>>> > (virtual) count vs real rx and vice versa ?
>>>> >
>>>> > Just some thougths...
>>>> > -Carlos
>>>> >
>>>> >
>>>> > Maarten Vervoorn @ 15/08/2012 04:34 -0300 dixit:
>>>> >
>>>> >> Dear all,
>>>> >>
>>>> >> Can anyone help me with this ICMP drop issue?
>>>> >>
>>>> >> I have created a CCIE R&S lab in GNS and used QinQ to connect the
>>>> virtual
>>>> >> router network to the real switches. All connectivity is working.
>>>> >>
>>>> >> When I ping form a virtual router to a physical switch I receive
>>>> drops
>>>> >> about 5 percent avarage.
>>>> >>
>>>> >> I installed GNS on a windows 2008 R2 64bit machine. 1 Xeon procesors
>>>> with
>>>> >> 4
>>>> >> cores each and 6 Gbit of memory
>>>> >> Idle PC is calculated and at 0% when the lab is booted
>>>> >> The NIC is a HP-NC382i DP (Broadcom chipset)
>>>> >> I use the HP configuration tooling to create serveral VLAN on the
>>>> adapter.
>>>> >> This VLAN is presented as a NIC in Windows which I use in GNS for a
>>>> >> virtual
>>>> >> router to real switch connection
>>>> >>
>>>> >> When I ping from the real switch to the virtual router I receive no
>>>> drops
>>>> >> When I ping from router to router (virtually connected) I receive no
>>>> drops
>>>> >> When I ping from router to router ( through the physical switch
>>>> network) I
>>>> >> receive the same drops.
>>>> >> When I ping the cpu of the server and router is not increased.
>>>> >>
>>>> >> When I use wireshark to snif the traffic on the physical interface
>>>> of the
>>>> >> server I can see the ICMP request of the packet that times out. I do
>>>> not
>>>> >> receive that packet on the switch behind the port.
>>>> >>
>>>> >> When I look at the statistics of the NIC on the server I do not see
>>>> any
>>>> >> errors
>>>> >> When I look at the statistics of the router interface I do not see
>>>> any
>>>> >> errors
>>>> >> When I look at the statistics of the breakout switch port I do not
>>>> see any
>>>> >> errors
>>>> >> When I look at the statistics of the real switch port I do not see
>>>> any
>>>> >> errors
>>>> >>
>>>> >> I updated the drivers to the latest version. which didn't have any
>>>> result.
>>>> >> I replaced the cable. Which also didn't have any results
>>>> >>
>>>> >> Any one have any experience with this same issue? Some setteing on
>>>> the
>>>> >> adapter maybe. I have tried to enable or disable serveral things
>>>> like flow
>>>> >> control but this doesn't seem to help
>>>> >>
>>>> >> Thanks in advance
>>>> >>
>>>> >> Regards,
>>>> >>
>>>> >> Maarten Vervoorn
>>>> >>
>>>> >>
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>>>> >>
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>>>>
>>>> >> ___________
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>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> >>
>>>> > --
>>>> > Carlos G Mendioroz <tron_at_huapi.ba.ar> LW7 EQI Argentina
>>>>
>>>>
>>>> Blogs and organic groups at http://www.ccie.net
>>>>
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Received on Wed Aug 15 2012 - 09:28:33 ART