Problems with setting up DNS Redundancy - Mavericks

Question

Level 1

0 points

Problems with setting up DNS Redundancy - Mavericks

Hi All,

I'm attempting to setup a 2nd OSX server for OD, DNS and DHCP redundancy. I've followed all instructions I have found online but I'm having problems . below is what I'm running and what I've done.

Main server.

server.superannuationproperty.org - 10.0.0.1.

Failover 2nd server

server2.superannuationproperty.org - 10.0.0.9

1. I setup zone transfers on the Primary and Reverse zones - main server.

2 On Failover server added a Secondary zone - server.superannuationproperty.org with IP 10.0.0.1 and for the Reverse in my case was 1.0.0.10.in-addr.arpa and 10.0.0.1.

3. Added forwarding servers on the Failover as 8.8.8.8 and ISP DNS server (as it is on the main server)

4 Changed Failover DNS settings to point to itself first then to the ISP DNS and 8.8.8.8

Internet is working fine on the server but I can't ping server2.superannuationproperty.org and when I run a "checkhostname" I get "The DNS hostname is not available, please repair DNS and re-run this tool" message.

I assume this is why my OD replica isn't working too. I'm able to add the replica ok but when creating new users on the main, they show up on the failover but with "not allowed" I'm also unable to login to clients when the main server is powered off.

Does anyone know what I'm doing wrong here??

Thanks in advance.

Mac Mini Server (Late 2012), null

Posted on Mar 1, 2015 7:36 PM

Reply

Answer 1

Mar 2, 2015 2:25 AM in response to new2mavsrv

I could not tell for certain from your post which DNS servers you are advertising via DHCP. In your case you should be advertising

10.0.0.1

10.0.0.9

It is normally considered a bad idea to advertise any others via DHCP in your setup, and remember that any other requests would automatically get redirected to 8.8.8.8 and your ISP by your DNS server(s) as you have set up those for forwarding on both your DNS servers.

With regards to running two DHCP servers, there are two approaches, first you can set each DHCP server to check for an already running DHCP server on the network when it starts up and if it finds one it will then turn itself off to prevent a conflict. Unfortunately the Apple DHCP server is not clever enough by itself to continue checking to see if the other server later fails. (You could possible write your own script to do this.) The other more common approach is to define two DHCP servers with mostly identical settings except each will use a non-overlapping range of client IP addresses. Then clients will use whichever DHCP server responds first. Each range will need to be big enough for all the devices and not just half of them.

You can test each DNS server is responding to requests properly by doing the following in Terminal

nslookup server.superannuationproperty.org 10.0.0.1

nslookup server.superannuationproperty.org 10.0.0.9

nslookup 10.0.0.1 10.0.0.1

nslookup 10.0.0.1 10.0.0.9

nslookup server2.superannuationproperty.org 10.0.0.1

nslookup server2.superannuationproperty.org.10.0.0.9

nslookup 10.0.0.9 10.0.0.1

nslookup 10.0.0.9 10.0.0.9

Reply

Answer 2

new2mavsrv Author

Level 1

0 points

Mar 2, 2015 9:43 PM in response to John Lockwood

Thanks for your reply. I have DHCP redundancy working by dishing out two different ranges and yes i've set DHCP so clients get both servers. 10.0.0.1 and 10.0.0.9

I still can't get DNS to work however.... after stuffing around with it today i decided to start from scratch and rebuilt the failover server with a fresh copy of Mavericks and Server.

I gave the server a local address this time server2.local

I setup a secondary zone of Server.superannuationproperty.org - 10.0.0.1 and Reverse of 1.0.0.10.in-addr.arpa - 10.0.0.1

After running a "checkhostname" i'm still getting "The DNS hostname is not available, please repair DNS and re-run this tool."

I ran nslookup on 10.0.0.9 with "server can't find 9.0.0.10.in-addr.arpa.: NXDOMAIN" and on server2.local with "server can't find server2.local: NXDOMAIN"

i can ping server2.local however...

I can't figure out what i'm doing wrong. I don't want to attempt to join the Master OD until I have DNS sorted out.

I checked the logs under DNS config see below. From what i can see it's transferred the zone info from the main server, i just don't know what's wrong??? Thanks.

3-Mar-2015 15:09:18.242 managed-keys-zone/com.apple.ServerAdmin.DNS.public: loaded serial 0

03-Mar-2015 15:09:18.244 zone 0.0.127.in-addr.arpa/IN/com.apple.ServerAdmin.DNS.public: loaded serial 1997022700

03-Mar-2015 15:09:18.249 zone localhost/IN/com.apple.ServerAdmin.DNS.public: loaded serial 42

03-Mar-2015 15:09:18.249 all zones loaded

03-Mar-2015 15:09:18.249 running

03-Mar-2015 15:09:18.251 zone 1.0.0.10.in-addr.arpa/IN/com.apple.ServerAdmin.DNS.public: Transfer started.

03-Mar-2015 15:09:18.252 transfer of '1.0.0.10.in-addr.arpa/IN/com.apple.ServerAdmin.DNS.public' from 10.0.0.1#53: connected using 10.0.0.9#50354

03-Mar-2015 15:09:18.294 zone 1.0.0.10.in-addr.arpa/IN/com.apple.ServerAdmin.DNS.public: transferred serial 2015030303

03-Mar-2015 15:09:18.294 transfer of '1.0.0.10.in-addr.arpa/IN/com.apple.ServerAdmin.DNS.public' from 10.0.0.1#53: Transfer completed: 1 messages, 4 records, 178 bytes, 0.042 secs (4238 bytes/sec)

03-Mar-2015 15:09:18.294 zone 1.0.0.10.in-addr.arpa/IN/com.apple.ServerAdmin.DNS.public: sending notifies (serial 2015030303)

03-Mar-2015 15:09:18.752 zone server.superannuationproperty.org/IN/com.apple.ServerAdmin.DNS.public: Transfer started.

03-Mar-2015 15:09:18.752 transfer of 'server.superannuationproperty.org/IN/com.apple.ServerAdmin.DNS.public' from 10.0.0.1#53: connected using 10.0.0.9#50355

03-Mar-2015 15:09:18.754 zone server.superannuationproperty.org/IN/com.apple.ServerAdmin.DNS.public: transferred serial 2015030303

03-Mar-2015 15:09:18.754 transfer of 'server.superannuationproperty.org/IN/com.apple.ServerAdmin.DNS.public' from 10.0.0.1#53: Transfer completed: 1 messages, 4 records, 159 bytes, 0.001 secs (159000 bytes/sec)

03-Mar-2015 15:10:21.878 received SIGHUP signal to reload zones

03-Mar-2015 15:10:21.903 loading configuration from '/Library/Server/named/named.conf'

03-Mar-2015 15:10:21.904 using default UDP/IPv4 port range: [49152, 65535]

03-Mar-2015 15:10:21.904 using default UDP/IPv6 port range: [49152, 65535]

03-Mar-2015 15:10:21.921 sizing zone task pool based on 5 zones

03-Mar-2015 15:10:21.950 reloading configuration succeeded

03-Mar-2015 15:10:21.960 reloading zones succeeded

03-Mar-2015 15:10:21.992 all zones loaded

03-Mar-2015 15:10:21.992 running

03-Mar-2015 15:22:37.333 received SIGHUP signal to reload zones

03-Mar-2015 15:22:37.333 loading configuration from '/Library/Server/named/named.conf'

03-Mar-2015 15:22:37.334 using default UDP/IPv4 port range: [49152, 65535]

03-Mar-2015 15:22:37.334 using default UDP/IPv6 port range: [49152, 65535]

03-Mar-2015 15:22:37.350 sizing zone task pool based on 5 zones

03-Mar-2015 15:22:37.354 reloading configuration succeeded

03-Mar-2015 15:22:37.355 reloading zones succeeded

03-Mar-2015 15:22:37.365 all zones loaded

03-Mar-2015 15:22:37.365 running

03-Mar-2015 15:24:19.671 received SIGHUP signal to reload zones

03-Mar-2015 15:24:19.671 loading configuration from '/Library/Server/named/named.conf'

03-Mar-2015 15:24:19.672 using default UDP/IPv4 port range: [49152, 65535]

03-Mar-2015 15:24:19.672 using default UDP/IPv6 port range: [49152, 65535]

03-Mar-2015 15:24:19.688 sizing zone task pool based on 5 zones

03-Mar-2015 15:24:19.694 reloading configuration succeeded

03-Mar-2015 15:24:19.695 reloading zones succeeded

03-Mar-2015 15:24:19.703 all zones loaded

03-Mar-2015 15:24:19.704 running

Reply