Number of Domains

Linode has a free DNS service, which is pretty straightforward to use. So there's little reason for you to run a DNS server on your linode. It would be a waste of your valuable RAM…..

Unless:

1) You have an awful lot of domains to take care of automatically;

2) You want some feature that isn't offered by Linode DNS; or

3) You have clients who expect their hosting provider to run their own name servers.

I might qualify for the first one. One of my Linodes runs primarily as a DNS server (with more uses planned) with two IPs; one is used for slave DNS for my private business, and the other is used for master DNS for someone else. The slave DNS serves 90 domains (not counting belonging temporary zones), the master serves 324 domains.

Then again, I've gotten used to fiddling around with the BIND zone files directly…