RE: AD Replication problem

The packet size does not limit the AD replication. packet size depends on the
Maximal Transmission Unit (MTU), which lives between second and third OSI
layers, while AD replication is way above in the OSI model.
MTU is medium specific (i.e. Ethernet's default MTU is 1500, hence largest
IP packet would be 1472=1500-28(IP headers) )
What matters is the ability of the interfaces to determine the maximal MTU
of the link connecting distant peers.

My guess is that your ISP has changed MTU settings on one of the routers in
an offending way - instead of fragmenting the packets to the correct MTU and
passing them over, it just drops the packets exceeding it's interface's MTU
setting, without providing correct ICMP feedback to the sender.

--
Smith & Wesson - the original point and click interface


"Mr.B" wrote:

> We had problems with wan lines between several lines. There was a storm and
> it cut down optical lanes of ISP provider. Several sites were unreachable. So
> I would get several KCC errors. Those errors are continuing and getting
> worse.
> I start to ping sites and getting errors when packet reaches beyond certain
> size, witch was not happening before.
>
> Ping –l 1472 Server
> I get response 2ms
> And if i ping with size 1473 , I get time out
>
> Before broken optical lines i could ping sites with packets grater than
> 9000bytes. There was response time like 200ms .
>
> What is the size of the packets that must come through, so that the AD
> replication success.
>
.

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