Negative greeting error while sending email
MTA is not able to send emails when "localhost[127.0.0.1]" is missing from zimbraMtaMyNetworks
Problem
Negative greeting 554 5.7.1 <localhost[127.0.0.1] error in zimbra.log while sending email.
May 31 03:28:16 mta2 postfix/smtp[2326054]: 02DEC202BDF0: to=<bob@example.com>, relay=127.0.0.1[127.0.0.1]:10026, delay=0.18, delays=0.1/0.01/0/0.06, dsn=4.5.0, status=deferred (host 127.0.0.1[127.0.0.1] said: 451 4.5.0 id=2321174-01 - Temporary MTA failure on relaying, From MTA() during fwd-connect (Negative greeting: 554 5.7.1 <localhost[127.0.0.1]>: Client host rejected: Access denied): id=2321174-01 (in reply to end of DATA command))
Solution
Check the zimbraMtaMyNetworks output in all MTA servers:
zmprov -l gs zimbra.example.com zimbraMtaMyNetworks
Confirm localhost (127.0.0.0/8 [::1]/128) network added or not. Add localhost network into zimbraMtaMyNetworks.
Example:
zmprov ms `zmhostname` zimbraMtaMyNetworks '127.0.0.0/8 [::1]/128 10.0.1.34/32 10.0.2.35/32' zmmtactl restart