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Saty_Attota_201's avatar
Saty_Attota_201
Icon for Nimbostratus rankNimbostratus
Jul 02, 2018

SMTP mail - getting error 550 5.7.1 Unable to relay for

I did set up mailhub. Could see entry in /etc/ssmtp/ssmtp.conf as expected.   Created SMTP configuration from System -> Device -> SMTP   Later I issued the following commands:   modify /sys ...
application delivery
BIG-IP
Super-NetOps
TMOS
Chase_Abbott's avatar
Chase_Abbott
Icon for Admin rankAdmin
Jul 02, 2018

You should be able to telnet from the BIGP-IP to Exchange and send an email. If that cannot happen, Exchange still needs further configuration. In this case, you're using BIG-IP like any telnet client.

 

  1. Verify the IP you specified to relay IS the actual IP being used. If you setup automap versus SNAT pool. BIG-IP can have many sending IP addresses so SMTP/Transport Agent logs will verify (or tcpdump/wireshark the Exchange Transport/CAS box).
  2. Is requires authentication enabled for the receive connector? 550 5.71 can fail due to the receive connection auth settings.
  3. Is the sierracollege.edu setup as a receiving domain for this? The failure happened immediately after RCPT instead of completing the mail setup .

You should be able to complete a basic SMTP handshake in any telnet client to validate this works. If that fails, you'll need to investigate the incoming receive connector, transport agent, and other Exchange related configs prior. Best step is to simplify the config to basic send/receive before introducing new configs and proxies.

 

If you want, obfusicate and send along transport logs of the session.