tcp connection reset therefore unable to send mail ...i think

[dogsbod]

Hi,

I'm unable to send email via a sonicwall firewall.
Ethereal shows that when our mailsweeper machine attempts to initaite conversation with wan ip inorder to send mail the latter responds with RST\ACK, ethereal states
"reset casue: rctcpi". Unable to determine what this means.
I also cannot ping the wan ip, but can ping external addresses and receive mail.

lan---exchnage server---mailsweeper----soniwall---internet

any help greatly appreciated...

 

[thedaver]

Is the other end of the WAN using private IP? Is there static routing in the firewall that would prevent return traffic? Any filters in the firewall that would block ports/packets?

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[dogsbod]

the other end being the external interface of the firewall? then its a public IP. I'm letting 'all' traffic out of the firewall and only smtp in. As far as static routing, there is nothing defined. Is being unable to ping the wan ip from the lan the basis of why I can't send email? Thanks

 

[xfer4242]

Reset Cause of RCTCPI is code generated by the Sonicwall. This does not indicate why it was dropped, but just tells you that the RST packet was actually generated by the Sonicwall. Check your rules. If the rule is ok, then go into the dial.html page (

http://xxx.xxx.xxx/diag.html)

and look for a SYN Flood Prevention option (You may not have it). If you find it, uncheck it and try again.

The sonicwall may have killed the connection becuase its blocked, something wrong with the three way handshake, or a packet came in out of order following the tcp connection.

Good luck...