How to enable dns on a NetApp running ONTAP

 








 

I had to enable dns on the NetApp ONTAP device the other day and as I am in the thick of learning NetApp, I thought I would write this one down. It is pretty easy but you need to do this through the cli.

At first, DNS is not enabled. You can see this in the System Manager UI:

 
















You have to drop to the command line and edit a few files to enable dns. The cutdown FreeBSD cli is, yep, cutdown. However, once you know your way around, it is pretty easy. When you need to write and read a file, there are 2 key commands:

wrfile
rdfile

wrfile writes to a file. I don't like this but you need to press CTRL-C to quit out of the file and you get this message when you do so:

read: error reading standard input: Interrupted system call

However you can also use wrfile -a which appends to the file. It's not vi, that's for sure.

However, back to the point. Below shows how one can set up DNS and a sneaky gotcha you need to be aware of.

If you just try to enable dns from the command options dns.enable on, you maight get this message:

Setting option dns.enable to 'off' conflicts with /etc/rc that sets it to 'on'

There is a rc file that loads services on boot and here is where DNS is set, which by default is off as you can see:

ontap> rdfile /etc/rc
hostname ontap
ifconfig e0a `hostname`-e0a mediatype auto flowcontrol full netmask 255.255.255.0 mtusize 1500
route add default 10.10.10.1 1
routed on
options dns.enable off
options nis.enable off
savecore

You can see it states dns.enable off. This means, whilst you can start dns by running options dns.enable on, with the rc file set this way, dns.enable on is not persistent. So first you need to update the /etc/rc file and set dns to be enabled.

Hint : You can rdfile /etc/rc then copy and paste the contents appropriately in when you run the wrfile /etc/rc. You'll get the drift when you have a go yourself. So here goes:

ontap> wrfile /etc/rc
hostname ontap
ifconfig e0a `hostname`-e0a mediatype auto flowcontrol full netmask 255.255.255.0 mtusize 1500
route add default 10.10.10.1 1
routed on
options dns.enable on
options nis.enable off
read: error reading standard input: Interrupted system call

Here you can see this read: error reading standard input: Interrupted system call. This is because you have to CTRL-C out of the wrfile command to save your changes. If ANYONE knows a way around htis, please send a commnt. However, a man wrfile doesn't suggest a way.

So now, you have the /etc/rc file set up with dns enables, you need to change the /etc/resolv.conf. Here you can use the wrfile -a command. Just append your dns nameserver like so:

ontap> wrfile -a /etc/resolv.conf nameserver 10.10.10.10
Lastly, you need to run the following command to trun on dns

ontap> options dns.enable on

And there you have it. To prove dns is now running, the UI will show your changes:

Now I can continue setting up CIFS and adding the ONTAP device to AD. Pretty straight forward once you know how.