Thank you so much for your reply:
This is tail of zimbra log when I try to send an email from another email which name is
khucnam.hai@mcsoft.vn to
admin@domainname.com
root@domainname:/etc# tail /var/log/zimbra.log
Apr 28 15:58:58 domainname postfix/smtpd[28517]: connect from localhost.localdomain[127.0.0.1]
Apr 28 15:58:58 domainname postfix/smtpd[28517]: 61EE99BC62: client=localhost.localdomain[127.0.0.1]
Apr 28 15:58:58 domainname postfix/cleanup[28510]: 61EE99BC62: message-id=<1209373106.9689.16.camel@zilotvn>
Apr 28 15:58:58 domainame postfix/qmgr[25517]: 61EE99BC62: from=
, size=1293, nrcpt=1 (queue active)
Apr 28 15:58:58 domainname postfix/smtpd[28517]: disconnect from localhost.localdomain[127.0.0.1]
Apr 28 15:58:58 domainname amavis[25705]: (25705-02) FWD via SMTP: -> , BODY=8BITMIME 250 2.6.0 Ok, id=25705-02, from MTA([127.0.0.1]:10025): 250 Ok: queued as 61EE99BC62
Apr 28 15:58:58 domainname amavis[25705]: (25705-02) Passed CLEAN, [203.162.1.108] [203.162.1.108] -> , Message-ID: <1209373106.9689.16.camel@zilotvn>, mail_id: kt+YhQhr8OfF, Hits: -2.413, queued_as: 61EE99BC62, 344 ms
Apr 28 15:58:58 domainnname postfix/smtp[28514]: F3FC99BC58: to=, relay=127.0.0.1[127.0.0.1], delay=1, status=sent (250 2.6.0 Ok, id=25705-02, from MTA([127.0.0.1]:10025): 250 Ok: queued as 61EE99BC62)
Apr 28 15:58:58 domainname postfix/qmgr[25517]: 61EE99BC62: to=, relay=none, delay=0, status=deferred (delivery temporarily suspended: Host or domain name not found. Name service error for name=domainname.com type=A: Host not found, try again)
Apr 28 15:58:58 domainname postfix/qmgr[25517]: F3FC99BC58: removed
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Ping domainname.com from localhost:
root@domainname:/etc# ping domainname.com
PING domainname.com (10.75.85.30) 56(84) bytes of data.
64 bytes from domainname.com (10.75.85.30): icmp_seq=1 ttl=64 time=0.025 ms
64 bytes from domainname.com (10.75.85.30): icmp_seq=2 ttl=64 time=0.023 ms
64 bytes from domainname.com (10.75.85.30): icmp_seq=3 ttl=64 time=0.024 ms
64 bytes from domainname.com (10.75.85.30): icmp_seq=4 ttl=64 time=0.020 ms
64 bytes from domainname.com (10.75.85.30): icmp_seq=5 ttl=64 time=0.025 ms
Ping domainname.com from the Internet
zilotvn@zilotvn:/$ ping domainname.com
PING domainname.com (222.252.22.202) 56(84) bytes of data.
64 bytes from localhost (222.252.22.202): icmp_seq=1 ttl=120 time=929 ms
64 bytes from localhost (222.252.22.202): icmp_seq=2 ttl=120 time=856 ms
64 bytes from localhost (222.252.22.202): icmp_seq=3 ttl=120 time=809 ms
64 bytes from localhost (222.252.22.202): icmp_seq=4 ttl=120 time=824 ms
64 bytes from localhost (222.252.22.202): icmp_seq=5 ttl=120 time=666 ms