Over the years I've found myself using many different naming schemes for servers under my control. I came across a naming convention that finally feels correct. That blog post is quite well written and will let it stand on its own. In the event it ever disappears the important bits (and those where I've personalized it) are included here.
There are ultimately two or three DNS names that each host receives. The first is a permanent unique identifier for the host. The blog post offers the mnemonic encoding project as a way to generate the hostnames. I've built my own generator that accomplishes the same effect with a vastly larger potential space (not that I need it). It has the added bonus of generating interesting names that are easy to talk about. Some samples (none real):
brave-noon-funeral.stelfox.net obscured-dawn-bush.stelfox.net striking-evening-moss.stelfox.net
The second name is a CNAME intended to be redirectable to new instances or servers if an old one dies or otherwise needs to be decommissioned. This is tied directly to the function of the machine, while letting the machine behind the name be replaceable.
This name is a combination of a short purpose code, a serial number (indicating the specific instances of the purpose), what environment it runs in (production, staging, etc), a location code, and your domain. The blog post also includes a country code but I've chose to leave that out.
The last name(s) are convenience names intended to expose services to users.
These domains are along the lines of
webmail.stelfox.net and can point at
multiple instances of purpose names or unique instance names.
Serials are unique to the purpose and site and are zero padded integers (01, 02). Serials are only unique within their local location code. Environment should not be taken into account when calculating the serial.
List of Purposes
These three letter purpose codes are kind of arbitrary. For consistency this documents the purpose codes I've generated for specific uses.
- app - Application server (non-web)
- sql - Database server
- ftp - SFTP server
- mta - Mail server
- dns - Name server
- cfg - Configuration management server (Puppet, Ansible, etc.)
- mon - Monitoring server (Nagios, Sensu, etc.)
- prx - Proxy / Load balancer (software)
- ssh - SSH jump / Bastion host
- sto - Storage server
- vcs - Version control software (Git)
- vmm - Virtual machine manager
- web - Web server
- cch - Cache server (Redis, Memcached, etc.)
- vpn - VPN server
List of Environments
Similar to the purpose codes, these are the chosen three letter codes for different environments.
- dev - Development
- tst - Testing
- stg - Staging
- prd - Production
Location codes in the original blog post are broken into two segments the local code based on the United Nations Code for Trade and Transport Locations (UN/LOCODE) which is more specific than IATA airport codes and the country code. For my uses I leave the country code out.