Problem on Setting DNS in Unbuntu 10.04LTS

[vaiocliehk]

I have setup BIND9 in ubuntu 10.04LTS with the configuration below, but still cant sent and receive email.

Zimbra Server IP: 192.168.44.100
Domain: example.com

/etc/resolv.conf
nameserver 192.168.44.100

/etc/hosts
127.0.0.1 localhost.localdomain localhost
192.168.44.100 mail.example.com mail

/etc/bind/named.conf.local
zone "example.com"{
type master;
file "/etc/bind/db.example.com";
};

/etc/bind/db.example.com

$TTL 604800
@ IN SOA mail.example.com. admin.example.com. (
20101128 ; Serial
604800 ; Refresh
86400 ; Retry
2419200 ; Expire
604800 ) ; Negative Cache TTL
;
@ IN NS 192.168.44.100
IN MX 10 mail.example.com
IN A 192.168.44.100
mail IN A 192.168.44.100


What wrong with my setting?
Do anybody could give a helpful hand to me?

[zelthian]

You might want to start here:

DNS for Rocket Scientists - Contents

Check chapter 8 on DNS Resource Records. A lot of what you're doing is a bit wonky.

[support@imiraclehk.com]

Would you mind to point out where the mistake or wonky is?
I'm sorry that i'm newbie of linux.

[zelthian]

If you're a newbie of Linux, you'd probably be better off using the OS you are familiar with to run your DNS server. You really shouldn't run DNS on the same server as your Zimbra server anyway, unless you have to, and that looks like exactly what you are trying to do. That said, your DNS setup may not be the reason you can't send and receive email in the first place.

For a good primer on BIND9, check out this page:

https://help.ubuntu.com/community/BIND9ServerHowto

A forum like this is really not the best place for someone to teach you BIND from scratch. Use that link as a primer, and my original like for a more in-depth study.

That said, my Silly Wild Academic Guess would be that you haven't indicated any forwarders in the named.conf.options file, which would prevent the Zimbra server from resolving other Internet domain names, thus preventing it from sending mail out. And, if you are trying to receive email FROM the Internet, then you need a domain and a public DNS entry for the MX record (and a public A record) for your Zimbra server that works from the Internet. And that's a whole other discussion (public facing IPs, NAT forwarding, dynamic DNS and such).

Again, these are things that are best learned as part of a general education on DNS.

[phoenix]

Originally Posted by vaiocliehk

I have setup BIND9 in ubuntu 10.04LTS with the configuration below, but still cant sent and receive email.

Why do you think it's a DNS problem? What errors do you see in the log files? What are the symptoms of your problem? Have you disabled the firewall and AppArmor on this server? Are all the Zimbra services running?

[vaiocliehk]

1. installing zimbra, the system show error of mx record.
2. after install zimbra, error in check mx record in domain and cant send and receive email.

where can i check the log file?

[phoenix]

Originally Posted by vaiocliehk

1. installing zimbra, the system show error of mx record.
2. after install zimbra, error in check mx record in domain and cant send and receive email.

where can i check the log file?

Although your DNS records appear to be OK that you posted earlier I'd suggest you go to the Split DNS article and run all the commands (on the Zimbra server) in the 'Verify...' section of that article and post the output here if you still have questions.

What about the answers to my other questions?

[zelthian]

Did you restart networking and bind, or restart the server, after you made the changes to hosts, resolv.conf, and the BIND config files?

[zelthian]

vaiocliehk, please post your /etc/hostname file.

In the meantime, let me post some examples. I'll use the IP you set up in your files. This assumes that you don't need to send email to the Internet; you don't want your email coming from "example.com".

This should help get past the mx record errors on your host. You may want to reboot after you make this changes and be sure your DNS settings on your network card on the server are still pointing to this IP after reboot.

This should let you send and receive email WITHIN the server. Since you don't own the example.com domain, you wouldn't be able to receive email from the Internet, and I would strongly advise not trying to send email to the Internet from your server using the "example.com" domain.

NOTE: The IP addresses of the forwarders in the named.conf.options file are for the public Google DNS servers. You can change those to the IPs of the DNS servers of your ISP.

NOTE2: Be sure you increment (add 1 to) the number next to "serial" in your db. files and restart bind (sudo /etc/init.d/bind9 restart) every time you make a change to these files or the BIND process won't pick up the changes.

/etc/named.conf.local

zone "example.com" {
	type master;
	file "/etc/bind/db.example.com";
	};

zone "44.168.192.in-addr.arpa" {
        type master;
        notify no;
        file "/etc/bind/db.192";
};

/etc/bind/db.example.com

$TTL	604800
@	IN	SOA	mail.example.com. root.example.com (
			      2		; Serial
			 604800		; Refresh
			  86400		; Retry
			2419200		; Expire
			 604800 )	; Negative Cache TTL
;

@	IN	NS	mail.example.com.
@	IN	MX	10	mail.example.com.
mail	IN	A	192.168.44.100

/etc/bind/db.192

$TTL	604800
@       IN      SOA     mail.example.com. root.example.com. (
                              2         ; Serial
                         604800         ; Refresh
                          86400         ; Retry
                        2419200         ; Expire
                         604800 )       ; Negative Cache TTL
;
@	IN      NS      mail.example.com.
100	IN	PTR	mail.example.com.

/etc/bind/named.conf.options

options {
	directory "/var/cache/bind";

	  forwarders {
		8.8.8.8;
		8.8.4.4;
	 };

	auth-nxdomain no;    # conform to RFC1035
	listen-on-v6 { any; };
};

[vaiocliehk]

actually i already restart bind9 service or reboot server after i have modified the configuration file.
In fact i need to using "example.com" this domain for email outgoing and incoming to internet. but i will first try the local mail sending.
Thanks all support