Second DNS server works finally

You need to add the slave's server to the transfer setting in /etc/named.conf, on the master.

allow-transfer  { xxx; };

I have DirectSlave on the second server.

The cloud control panel on RamNode rocks.

If they had block storage, and a cheaper VDS, I'd switch the main server to them too. But, BuyVM is cheap, will be hard to offer the same prices.

Their control panel, has a firewall, just delete the allow all incoming rules.

Nice, no SWAP, and only 512 MB of RAM, it's the cheapest $3 plan, under standard.

Guess, my DNS doesn't need much RAM.

And the CPU looks to mostly be under 10%.

You can also allow only a specific IP to access certain ports.

The hardest part, was getting it to connect, the firewall on the slave is fine. I forgot CSF is configured to block outgoing ports that aren't allowed. After adding the port, I was able to connect from this server.

I'll setup a on the VPS some other day. So if the main server is down, you might know why. Unless it's another BuyVM outage, their entire site went down, last time that happened. And it lasted a while.