I am having a trouble at sending email with zimbra, sometimes I have to restart the network service (using service network restart syntax, FYI I am using CentOS 5.1). The SMTP Server I am using is the SMTP server provided by my ISP.
And when the emails are deferred, I tried to telnet the ISP SMTP Server and it ended with failure. After I restart the network service, I can normally telnet the SMTP server again. And when I check to zimbra admin interface, the error status in the deferred mail item view is network connection timed out. Is the problem is in my network card or the connection to the SMTP server or something else...?
Do anyone here have experienced the same problem like me?
Thanks in advance