I follow this article and resolved the problem of cert expired . Now my mail system work well . But I only prolonged the date of my credentials one more year. It means next year, i also need to repeat today's work. I modified the entry to 3650 according to the sentences of " If you want to change the duration of the certificate from the default (365 days), modify the "default_days" entry in the file /opt/zimbra/conf/zmssl.cnf.in ". BUT after "zmcontrol stop / zmcontrol start" , I also found the duration of certificate is one year(by the command "/opt/zimbra/bin/zmcertmgr viewdeployedcrt all").
Now my question is : how to change the duration of certificate to 5 or 10 or more years by cli .