Sometimes Mail Detected as spam

[wkey]

Hi!

i have zimbra with hostname(example) : mail.zimbra.com, and make another domain inside it with name zimbra.com and used it as primary domain at global config.
so my accounts will be : user1@zimbra.com, user2@zimbra.com not user1@mail.zimbra.com, user2@mail.zimbra.com.

and this is my configuration :

[root@mail ~]# cat /etc/hosts
127.0.0.1      localhost localhost.localdomain localhost4 localhost4.localdomain4
192.168.0.5   mail.zimbra.com mail

[root@ ~]# host 192.168.0.5
5.0.168.192.in-addr.arpa domain name pointer mail.zimbra.com.

dig mx to mail.zimbra.com and zimbra.com return with QUESTION, ANSWER, and AUTHORITY section. And the status was noerror

the problem is, when i send mail to gmail or yahoo, it still detected mail as spam, and i still get "Warning - Reverse DNS does not match SMTP Banner" from mxtoolbox.com.

for additional information, my server run under Port Address Translation,,

any ideas ?

sorry for my bad english, and Thanks !

[phoenix]

i have zimbra with hostname(example) : mail.zimbra.com, and make another domain inside it with name zimbra.com and used it as primary domain at global config.

What you should do is rename the "mail.domain.com" to "domain.com" - you don't need a second domain. Make sure your reverse DNS matches the SMTP banner and that you take a backup of your server before you make any changes.

[root@ ~]# host 192.168.0.5
5.0.168.192.in-addr.arpa domain name pointer mail.zimbra.com.

That 'host' command should be using the Public IP of your server to check the reverse DNS is correct.

dig mx to mail.zimbra.com and zimbra.com return with QUESTION, ANSWER, and AUTHORITY section. And the status was noerror

In future you should provide all the relevant output of those commands so it can be confirmed that what you have for DNS is correct.

[wkey]

i'm sorry, i wasn't give a proper information about my server before. You know, i can't give the real information of my server, so it's little difficult to tell the situation, but i'll try .

What you should do is rename the "mail.domain.com" to "domain.com" - you don't need a second domain

i have several domain :

192.168.0.3 : ns.zimbra.com = DNS server
192.168.0.4 : zimbra.com = Web server
192.168.0.5 : mail.zimbra.com = Mail server

domain "zimbra.com" have been used for web server and have separate ip from "mail.zimbra.com". The real domain for mail server is mail.zimbra.com not "zimbra.com". But i want my account on zimbra have name user@zimbra.com not user@mail.zimbra.com. So i created domain alias "zimbra.com" on my "mail.zimbra.com" mail server.

Make sure your reverse DNS matches the SMTP banner and that you take a backup of your server before you make any changes.

what method to use for check if my reverse DNS matches the SMTP banner or not ?

That 'host' command should be using the Public IP of your server to check the reverse DNS is correct.

im used host from private and public network and the result was fine.

[root@ ~]# host 192.168.0.5
5.0.168.192.in-addr.arpa domain name pointer mail.zimbra.com.

[root@ ~]# host my.ip.public.network
network.public.ip.my.in-addr.arpa domain name pointer mail.zimbra.com.

and for dig, the result was something like this :

; <<>> DiG 9.3.6-P1-RedHat-9.3.6-20.P1.el5 <<>> mx mail.zimbra.com
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 42754
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2

;; QUESTION SECTION:
;mail.zimbra.com.        IN      MX

;; ANSWER SECTION:
mail.zimbra.com. 40145 IN MX     10 mail.zimbra.com.

;; AUTHORITY SECTION:
mail.zimbra.com. 71244 IN     NS      ns.zimbra.com.

;; ADDITIONAL SECTION:
mail.zimbra.com. 74989 IN A      192.168.0.5
ns.zimbra.com. 40145 IN A      192.168.0.3

;; Query time: 0 msec
;; SERVER: 192.168.0.3#53(192.168.0.3)
;; WHEN: Fri Mar  8 14:11:19 2013
;; MSG SIZE  rcvd: 114

; <<>> DiG 9.3.6-P1-RedHat-9.3.6-20.P1.el5 <<>> mx zimbra.com
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 46177
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 2

;; QUESTION SECTION:
;zimbra.com.     IN      MX

;; ANSWER SECTION:
zimbra.com. 39710 IN     MX      10 mail.zimbra.com.

;; AUTHORITY SECTION:
zimbra.com. 70802 IN     NS      ns.zimbra.com.

;; ADDITIONAL SECTION:
mail.zimbra.com. 74547 IN A      192.168.0.5
ns.zimbra.com. 39703 IN A       192.168.0.3

;; Query time: 0 msec
;; SERVER: 192.168.0.3#53(192.168.0.3)
;; WHEN: Fri Mar  8 14:18:41 2013
;; MSG SIZE  rcvd: 114

once again, sorry for my bad english and Thanks !

[phoenix]

domain "zimbra.com" have been used for web server and have separate ip from "mail.zimbra.com". The real domain for mail server is mail.zimbra.com not "zimbra.com". But i want my account on zimbra have name user@zimbra.com not user@mail.zimbra.com. So i created domain alias "zimbra.com" on my "mail.zimbra.com" mail server.

You don't need a domain alias, all you need to do is rename the domain to your correct domain name - the domain name has nothing to do with your web server and will not interfere with it. Change the domain name and you won't have to bother with any additional steps of using a domain alias.

[wkey]

sorry but, i still didn't understand what you mean with rename the domain. Do you mean i must change my zimbra hostname and record on dns server to "domain.com" ?

[phoenix]

sorry but, i still didn't understand what you mean with rename the domain. Do you mean i must change my zimbra hostname and record on dns server to "domain.com" ?

What you are calling a "zimbra hostname" is the domain you have installed on the Zimbra server - it is a domain name when it's in this situation (or more correctly, a sub-domain) and if you want mail to go with the correct domain name then rename it.. Yes, you need valid DNS A & MX records for that domain - it will not interfere with your web server.

[wkey]

What you are calling a "zimbra hostname" is the domain you have installed on the Zimbra server - it is a domain name when it's in this situation (or more correctly, a sub-domain) and if you want mail to go with the correct domain name then rename it.. Yes, you need valid DNS A & MX records for that domain - it will not interfere with your web server.

okay, i understand now . But, is there no other way to fix my issue without changing my domain name (using domain alias)? it's quite a job to change domain in zimbra, change the record in dns server, and ask isp to change ptr record.

thanks !

[phoenix]

it's quite a job to change domain in zimbra,....

No it's not, it's one command (plus a backup first).

.... change the record in dns server,....

That's trivial to change your LAN DNS records.

..... and ask isp to change ptr record.

It's not necessary to change any DNS records with your ISP if you have ZCS behind a NAT router (which you have). When you say "change ptr record" which ptr record do you mean? All you should have in your external DNS is A & MX records (and nothing else) pointing to your Public IP address.

[wkey]

It's not necessary to change any DNS records with your ISP if you have ZCS behind a NAT router (which you have). When you say "change ptr record" which ptr record do you mean? All you should have in your external DNS is A & MX records (and nothing else) pointing to your Public IP address.

my zimbra isn't under NAT but PAT. My zimbra have its own public ip, different from ns server or web server (zimbra.com), if the server accessed from internal network the ip is 192.168.0.5, but if accessed from internet the ip is different(ip public).

So i need the isp to reconfigure pointer from mail.zimbra.com to zimbra.com since my zimbra server doesn't get reverse ns from my ns server, but direct from the ISP.