Thanks for everyone It's working after few hour.. My ISP may have blocked port 25 outbound It' working well now Sorry for answer so late, because of busy with my business Thanks again TOM
2014-02-21 11:53 GMT+08:00 Eric Kimminau <e...@kimminau.org>: > 1) Postfix has NO impact on telnet. If you cannot telnet outbound to a > remote port 25 the problem is that something on your host is blocking port > 25 or something upstream from you is blocking port 25. > > Can you perform the following: > > telnet localhost 25 > > If this works, you CAN telnet to port 25 locally. > > Then try a known Good SMTP server, such as Google: > # nslookup -q=MX gmail.com > Server: 209.172.41.202 > Address: 209.172.41.202#53 > > Non-authoritative answer: > gmail.com mail exchanger = 5 gmail-smtp-in.l.google.com. > gmail.com mail exchanger = 30 alt3.gmail-smtp-in.l.google.com. > gmail.com mail exchanger = 20 alt2.gmail-smtp-in.l.google.com. > gmail.com mail exchanger = 10 alt1.gmail-smtp-in.l.google.com. > gmail.com mail exchanger = 40 alt4.gmail-smtp-in.l.google.com. > > Authoritative answers can be found from: > alt3.gmail-smtp-in.l.google.com internet address = 173.194.70.27 > gmail-smtp-in.l.google.com internet address = 173.194.76.26 > alt4.gmail-smtp-in.l.google.com internet address = 173.194.69.27 > alt1.gmail-smtp-in.l.google.com internet address = 173.194.66.27 > alt2.gmail-smtp-in.l.google.com internet address = 74.125.136.27 > > [root@cl-t159-360cl ~]# telnet gmail-smtp-in.l.google.com 25 > Trying 173.194.76.26... > Connected to gmail-smtp-in.l.google.com (173.194.76.26). > Escape character is '^]'. > 220 mx.google.com ESMTP a3si2597941qao.15 - gsmtp > quit > Connection closed by foreign host. > > Make sure you actually have a service sunning on port 25, i.e.: > > netstat -an | grep 25 > tcp 0 0 0.0.0.0:25 0.0.0.0:* > LISTEN > i > > Make sure you do not have the inet service set to private in your > master.cf: > When I first started troubleshooting I got an error in the /var/log/maillog > Jan 30 11:34:45 list postfix/master[20710]: fatal: /etc/postfix/master.cf: > line 40: inet service cannot be private. > went into master.cf > found this > "smtp inet - - n - - smtp" > Changed first "-" to n > "smtp inet n - n - - smtp" > restarted post fix worked. > > Hope it helps. > > > > > On 2/20/2014 9:31 PM, Feel Zhou wrote: > > Hello, My friend > This is Tom, I'm sending my greeting from China. > Today, one of my postfix server can not telnet any other mail server's > port 25. It's working before 9:00am(bejing time CHina), I have restart the > mail server and reinstall the postfix. but it's looks like not working. How > can I fix this problem. Thanks for your help > TOM > > > -- > Eric Kimminau, Troop #284 recruiting...@kimminau.org > cell: 248-766-5353 > home: 248-393-8036 > >
