FWX_E_TCP_NOT_SYN_PACKET_DROPPED

[Boudewijn Plomp]

Hoi,

Heeft iemand van jullie een soortgelijk probleem kunnen oplossen zoals
deze...

I have two ISA Server 2004 Enterprise Editions running with Netwsork Load
Balancing (NLB). Each with five network adapters; one internal, one
external, two perimeter and one intra-array network. All adapters are
connected witch Cisco Catalyst switches, except the intra-array adapters.
When I check the logging I see lot's of Denied Connector with the error
result FWX_E_TCP_NOT_SYN_PACKET_DROPPED. Most problems seem to occur with
SMTP traffic. Everything seems to work fine, but I think it is not ok. Is it
possible that is has something to do with NLB and unicast in combination
with the Cisco Catalyst switches?

Does anyone know how to solve this issue or is this a bug?

Gr. Boudewijn

[Henk Steunenberg (Ms)]

Hello,

some SMTP Servers are sending RESETS back to the ISA Server after
the connection has already been fully closed at both ends. There is not data
loss,
just appears to be behavior of some SMTP relays.

regards,

Henk

Post by Boudewijn Plomp
Hoi,
Heeft iemand van jullie een soortgelijk probleem kunnen oplossen zoals
deze...
I have two ISA Server 2004 Enterprise Editions running with Netwsork Load
Balancing (NLB). Each with five network adapters; one internal, one
external, two perimeter and one intra-array network. All adapters are
connected witch Cisco Catalyst switches, except the intra-array adapters.
When I check the logging I see lot's of Denied Connector with the error
result FWX_E_TCP_NOT_SYN_PACKET_DROPPED. Most problems seem to occur with
SMTP traffic. Everything seems to work fine, but I think it is not ok. Is
it possible that is has something to do with NLB and unicast in
combination with the Cisco Catalyst switches?
Does anyone know how to solve this issue or is this a bug?
Gr. Boudewijn

[Boudewijn Plomp]

Henk,

I did some research. I think it has to do with ICMP Redirect. see this
Microsoft article...

ISA Server 2004 does not support traffic redirection
http://support.microsoft.com/default.aspx/kb/888042

Greetings,

Boudewijn

Of kan ik zeggen... groetjes?

Post by Henk Steunenberg (Ms)
Hello,
some SMTP Servers are sending RESETS back to the ISA Server after
the connection has already been fully closed at both ends. There is not
data loss,
just appears to be behavior of some SMTP relays.
regards,
Henk

Post by Boudewijn Plomp
Hoi,
Heeft iemand van jullie een soortgelijk probleem kunnen oplossen zoals
deze...
I have two ISA Server 2004 Enterprise Editions running with Netwsork Load
Balancing (NLB). Each with five network adapters; one internal, one
external, two perimeter and one intra-array network. All adapters are
connected witch Cisco Catalyst switches, except the intra-array adapters.
When I check the logging I see lot's of Denied Connector with the error
result FWX_E_TCP_NOT_SYN_PACKET_DROPPED. Most problems seem to occur with
SMTP traffic. Everything seems to work fine, but I think it is not ok. Is
it possible that is has something to do with NLB and unicast in
combination with the Cisco Catalyst switches?
Does anyone know how to solve this issue or is this a bug?
Gr. Boudewijn