Mail notater

blocking of server

Suddenly I couldn't send mail from mars.tekkom.dk to mercantec.dk. To figure out why I used telnet

Finding mailserver

[root@mars etc]#<input>dig -t MX mercantec.dk</input>

; <<>> DiG 9.4.2-P2 <<>> -t MX mercantec.dk
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 47863
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 6, ADDITIONAL: 0

;; QUESTION SECTION:
;mercantec.dk.                  IN      MX

;; ANSWER SECTION:
mercantec.dk.           86400   IN      MX      10 <notice>spa01.mercantec.dk</notice>.

Finding reason

[heth@mars ~]$<input> telnet spa01.mercantec.dk 25</input>
Trying 193.163.33.237...
Connected to spa01.mercantec.dk.
Escape character is '^]'.
220 spa01.mercantec.dk ESMTP (793039d8cf351cb2d25552ec1fbcb273)
<input>HELO mars.tekkom.dk</input>
250 spa01.mercantec.dk Hello cpe.atm2-0-75146.vgnxx2.customer.tele.dk [83.90.47.30], pleased to meet you
<input>MAIL FROM:<heht@mars.tekkom.dk></input>
250 Sender <heht@mars.tekkom.dk> OK
<input>RCPT TO:<heth@mercantec.dk></input>
554 Service unavailable; Client host [cpe.atm2-0-75146.vgnxx2.customer.tele.dk] 
<notice>blocked using Barracuda Reputation; http://bbl.barracudacentral.com/q.cgi?ip=83.90.47.30</notice>
Connection closed by foreign host.

Curing

Filled out form Barracuda removal form and wait one hour - they say. After 48 hours it worked.