Question to split-dns-article

[Alphaphi]

Hello everyone,

as I still have problems to get my zimbra server running, probably because of a DNS-problem, I have the following question regarding the split dns article:

It is said that one should set up a split horizon for the zone "server.example.com", which is the name of the machine zimbra is running on. The named.conf.options looks therefore like this:

[...]
zone "server.example.com" {
type master;
file "db.server.example.com";
};
[...]


Later, to verify everything, one should query

dig yourdomain.com any
dig yourdomain.com mx

I don't understand this for two reasons:

First: Why am I supposed to create a zone "server.example.com", but query later "yourdomain.com"? Where is the connection between these domains?

Second: assume that example.com = yourdomain.com: why set up a zone for server.example.com, but dig later for example.com? Setting up the server.example.com-zone does sure not affect the dns entries for example.com?

Is the article wrong, or am I thinking wrong? Where is the mistake? And: which dns entries make the point, the ones for example.com or the ones for server.example.com?

Thanks a lot!
Andre

[phoenix]

Why don't you just post the output of all the commands mentioned in the 'Verify..' section of the Split DNS article and start from there.

[Alphaphi]

Not sure what you mean - which output is missing?

Here again everything as far as I understand it. Nothing left out, and typed on the zimbra host itself:


# dig ourcompany.com mx

; <<>> DiG 9.4.2-P2.1 <<>> ourcompany.com mx
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4795
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1

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

;; ANSWER SECTION:
ourcompany.com. 300 IN MX 10 zimbra.ourcompany.com.

;; AUTHORITY SECTION:
ourcompany.com. 300 IN NS zimbra.ourcompany.com.

;; ADDITIONAL SECTION:
zimbra.ourcompany.com. 300 IN A 192.168.116.202

;; Query time: 0 msec
;; SERVER: 192.168.116.202#53(192.168.116.202)
;; WHEN: Fri Oct 15 12:18:24 2010
;; MSG SIZE rcvd: 88




# dig ourcompany.com any

; <<>> DiG 9.4.2-P2.1 <<>> ourcompany.com any
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 50993
;; flags: qr aa rd ra; QUERY: 1, ANSWER: 4, AUTHORITY: 0, ADDITIONAL: 1

;; QUESTION SECTION:
;ourcompany.com. IN ANY

;; ANSWER SECTION:
ourcompany.com. 300 IN SOA zimbra.ourcompany.com. it.ourcompany.com. 2010009 43200 3600 3600000 2592000
ourcompany.com. 300 IN A 192.168.116.202
ourcompany.com. 300 IN MX 10 zimbra.ourcompany.com.
ourcompany.com. 300 IN NS zimbra.ourcompany.com.

;; ADDITIONAL SECTION:
zimbra.ourcompany.com. 300 IN A 192.168.116.202

;; Query time: 0 msec
;; SERVER: 192.168.116.202#53(192.168.116.202)
;; WHEN: Fri Oct 15 12:18:52 2010
;; MSG SIZE rcvd: 152



# host $(hostname)
zimbra.ourcompany.com has address 192.168.116.202
zimbra.ourcompany.com mail is handled by 10 zimbra.ourcompany.com.




# cat /etc/resolv.conf
### BEGIN INFO
#
# Modified_by: NetworkManager
# Process: /usr/bin/NetworkManager
# Process_id: 4413
#
### END INFO

search ourcompany.com
nameserver 192.168.116.202



# cat /etc/hosts
#127.0.0.1 localhost
#127.0.1.1 zimbra.ourcompany.com zimbra

127.0.0.1 localhost.localdomain localhost
192.168.116.202 zimbra.ourcompany.com zimbra

# The following lines are desirable for IPv6 capable hosts
::1 ip6-localhost ip6-loopback
fe00::0 ip6-localnet
ff00::0 ip6-mcastprefix
ff02::1 ip6-allnodes
ff02::2 ip6-allrouters
ff02::3 ip6-allhosts

[phoenix]

Originally Posted by Alphaphi

Not sure what you mean - which output is missing?

I didn't say any output was 'missing', I was asking you to post the output for verification.

Originally Posted by Alphaphi

Here again everything as far as I understand it. Nothing left out, and typed on the zimbra host itself:

I haven't asked you for this information previously. The output, however, is correct and there's nothing wrong with it so I'm left wondering where or what is the problem?

[Alphaphi]

The problem is:

# rczimbra status
Host zimbra
antispam Stopped
zmamavisdctl is not running
antivirus Stopped
zmamavisdctl is not running
convertd Running
ldap Running
logger Running
mailbox Running
mta Running
snmp Running
spell Running
stats Running

$ zmamavisdctl start
Starting amavisd... The value of variable $myhostname is "zimbra", but should have been
a fully qualified domain name; perhaps uname(3) did not provide such.
You must explicitly assign a FQDN of this host to variable $myhostname
in amavisd.conf, or fix what uname(3) provides as a host's network name!
failed.

# grep '\$myhostname' /opt/zimbra/conf/amavisd.conf
$myhostname = 'zimbra'; # must be a fully-qualified domain name!


So amavisd won't start because of this non-FQDN hostname. And without amavisd listening on 10024 postfix is not able to deliver any mail.

Where does this single "zimbra" in $myhostname come from? What did I configure wrong?

[phoenix]

Originally Posted by Alphaphi

Where does this single "zimbra" in $myhostname come from? What did I configure wrong?

It comes from the uname command, so what does the output of the following show:

uname -n
hostname
hostname -f
/etc/hostname

[Alphaphi]

# uname -n
zimbra

# hostname
zimbra

# hostname -f
zimbra.ourcompany.com

# cat /etc/hostname
zimbra

Are these entries OK?

[phoenix]

Originally Posted by Alphaphi

# uname -n
zimbra

# hostname
zimbra

# hostname -f
zimbra.ourcompany.com

# cat /etc/hostname
zimbra

Are these entries OK?

No, they're not. change the entry in the hostnem file to your FQDN and save it. Run the following commands:

hostname zimbra.ourcompany.com
su - zimbra
zmamavisdctl start

It should start OK, if that works then you can reboot your server for the change to become permanent via the hostname file. Just in case you were going to ask, I don’t know enough about Ubuntu/Debian to tell you where when or how that file gets changed. I assume it gets set when you initially install the o/s and subsequent hostname or networking changes do not modify that file.

[Alphaphi]

# echo "zimbra.ourcompany.com" > /etc/hostname

# hostname zimbra.ourcompany.com

# hostname
zimbra.ourcompany.com

# uname -n
zimbra.ourcompany.com

# su - zimbra
$ zmamavisdctl start
Starting amavisd... The value of variable $myhostname is "zimbra", but should have been
a fully qualified domain name; perhaps uname(3) did not provide such.
You must explicitly assign a FQDN of this host to variable $myhostname
in amavisd.conf, or fix what uname(3) provides as a host's network name!
failed.

[Server reboot]

root@zimbra:~# hostname
zimbra.ourcompany.com

# rczimbra status
Host zimbra
antispam Stopped
zmamavisdctl is not running
antivirus Stopped
zmamavisdctl is not running
convertd Running
ldap Running
logger Running
mailbox Running
mta Running
snmp Running
spell Running
stats Running

# cat /etc/hostname
zimbra.ourcompany.com

# grep '\$myhostname' /opt/zimbra/conf/amavisd.conf
$myhostname = 'zimbra'; # must be a fully-qualified domain name!



So there must be another source for the hostname somewhere inside the zimbra configuration. Does it make sense to grep for it and change it by hand?

[Alphaphi]

Originally Posted by phoenix

No, they're not. change the entry in the hostnem file to your FQDN and save it. Run the following commands:

hostname zimbra.ourcompany.com
su - zimbra
zmamavisdctl start

It should start OK, if that works then you can reboot your server for the change to become permanent via the hostname file. Just in case you were going to ask, I don’t know enough about Ubuntu/Debian to tell you where when or how that file gets changed. I assume it gets set when you initially install the o/s and subsequent hostname or networking changes do not modify that file.

I now finally found the right solution: simply use "zmsetservername", and this does the rather complex modification.

ZmSetServerName - Zimbra :: Wiki for details.

This helped, and now my mail queues are flowing.

Thanks for everything!
Andre