Newbie with problems

Julian Anastasov ja at
Wed Aug 1 12:39:04 BST 2001


On Wed, 1 Aug 2001, Heiko Engler wrote:

> >        The setup is ok but your first posting is ambigous. My question
> >is whether all LVS connections from this service detect packets with
> >wrong checksum or you found this error only for one?
> This is the only connection I established (I just started). Really weird

	OK, I'm waiting for the final results.

> is: when I turn of the  sendmail on the real server and a packet is send
> from the real server with the AR flag set it gets through the virtual
> server and I get a connection refused on the client.

	This is expected. Don't turn off the sendmail before removing
it from the LVS table.

> The checksum problem only seem to occur with the SA flag on.
> Direct connections from the virtual server to real server on the smtp
> port is working too.

	Hm, may be the checksum is not updated after a packet mangling
in the PRE_ROUTING or in the FORWARD chain. An evidence for this will be
when all LVS connections detect wrong checksum. Can you test with a fresh
kernel, eg. 2.4.7?

> And when I use iptables -j DNAT to real server sendmail is answering
> correctly.
> Regards
> Heiko


Julian Anastasov <ja at>

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