Host Naming Guidelines
From Sysadmin
The following guidelines are offered for host naming. These guidelines apply regardless of the specific scheme in use.
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Guidelines
The following guidelines are offered for naming physical hosts. The guidelines apply equally whether personalised host naming is used or not.
Length
Keep the hostname short. In the past Unix hostnames were limited to 8 characters. This is no longer true on modern Unix systems, but long names should still be avoided. Users will be typing the name regularly. Forcing them to type longer names for the sake of it is pointless.
Semantics
Avoid semantic problems, especially puns. Avoid the use of words like up, down or terms that are used in the context of computers. Imagine a system named down and the ambiguity in the statement down is up.
Propriety
The hostname should not be or imply a swear word, curse, blasphemy, insult or offensive word. Remember that the hostname may be used in front of co-workers and clients.
Pronounceability
The hostname should be easily pronounceable by those who will commonly use the system. This may require evaluating pronounceability in more than one language.
Where short codes are used for the hosts these codes can be made to be pronounceable by using vowels within the code.
Leading zeros in host serial numbers can be awkward to pronounce. Experience shows that users will tend to drop leading zeros in hostname serial numbers in conversation, potentially introducing ambiguity and confusion.
Spelling
The hostname should be easy to spell. Use the regular spelling of a word. The hostname may be conveyed verbally and using an unusual spelling will cause avoidable problems. In particular the use of unusual spelling may cause confusion for those using a second language.
Ambiguity
The hostname must not be substantially similar to any other hostname or to the name of a human. In addition the hostname should not contain the name of major or well known geographical regions as this can easily be taken for the physical location of the system.
Domain Names
Avoid the use of domain names. This may cause confusion with the resolver library, although this is less of a problem than it was in the past.
Numerals
Don't start a hostname with a numeral. There is concern that this may cause problems with some resolver libraries. The use of numerals after the first character is acceptable and common.
Special Characters
Do not use any special character in a hostname except a dash (-).
Case
Hostnames are lower case by convention. It is strongly recommended to adhere to this as convention as using only lower case avoids potential problems with case sensitivity that might exist with different operating systems and applications.
Commonality
Avoid common words that may cause confusion when used in a computer discussion (like up or ping).
Hamming Distance
It can make sense to arrange the hostnames so that no two hostnames differ by only one character. This can reduces errors relating to a mistypes hostname. This criteria can be difficult to achieve in some situations, eg if hosts don't use leading serials in their hostname serial number.
