[133390] in North American Network Operators' Group
Re: SONET and MAC address
daemon@ATHENA.MIT.EDU (Jay Nakamura)
Wed Dec 8 19:33:23 2010
In-Reply-To: <AANLkTimOj7nc_-fOnyOHo8sUbNhw4U9Ez_yNBHp93mki@mail.gmail.com>
Date: Wed, 8 Dec 2010 19:33:11 -0500
From: Jay Nakamura <zeusdadog@gmail.com>
To: Danijel <theghost101@gmail.com>
Cc: NANOG <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
I think we narrowed it down to a cheap media converter they supplied.
It's a 10/100/1000 copper to gig fiber converter, which makes me think
it's got a low grade switch inside that doesn't have a per-VLAN FDB.
On Wed, Dec 8, 2010 at 5:46 PM, Danijel <theghost101@gmail.com> wrote:
> Same thing with Siemens and Huawei gear, there are "transparent" cards th=
at
> don't learn anything and L2 cards that do.
>
> --
> *blap*
>
>
> On Wed, Dec 8, 2010 at 22:57, Scott Berkman <scott@sberkman.net> wrote:
>
>> Don't know the FlashWave gear well, but in the Cisco ONS/Cerent world Gi=
gE
>> ports can be configured in different modes, some of which do in fact lea=
rn
>> MAC addresses. =A0Others emulate a single layer-2 link and as the vendor
>> stated, would not look at the MAC address at all.
>>
>> =A0 =A0 =A0 =A0-Scott
>>
>> -----Original Message-----
>> From: Jay Nakamura [mailto:zeusdadog@gmail.com]
>> Sent: Wednesday, December 08, 2010 3:33 PM
>> To: NANOG
>> Subject: SONET and MAC address
>>
>> We have a Gigabit Ethernet transport between cities by a vendor. =A0We f=
ound
>> that when there are identical MAC address that are on different VLANs on
>> different side of the circuit, one of the VLAN looses packets. =A0This
>> situation came up because two different networks that travel over the
>> Ethernet were using HSRP with the same virtual MAC address.
>>
>> The vendor says both sides are directly connected to Fujitsu SONET gear =
and
>> the equipment doesn't even look at the MAC address so it's not their
>> circuit. =A0All I know is, I can't recreate the problem if this circuit =
is
>> not
>> in the path.
>>
>> I haven't worked with Fujitsu SONET gear so I don't know if their claim =
is
>> true or not. =A0I vaguely remember someone talking about some equipment
>> actually having a builtin switch on the SONET port and that was messing =
up
>> the forwarding.
>>
>> Also, on one side of the circuit, there is a copper to fiber media
>> converter. =A0I am going to find out what model this is and see if that =
could
>> be the cause.
>>
>> Anyone have any thoughts on what I should look into or have the vendor l=
ook
>> into? =A0Anyone run into this situation?
>>
>> Thanks!
>>
>>
>>
>>
>
