max hostname lengths (MAXHOSTNAMELEN ?)

[Brad Knowles]

At 12:24 PM -0700 6/28/01, Sivakumar Thiyagarajan wrote:

>      Is there any maximum length for a host name or alias name for BIND
>  dns entries?

	Yup.  The limit is 63 characters for a single label element, and 
255 characters for the entire fully-qualified domain name.

>               If so, can this max length customised?

	Nope.  This is written into the standard and the protocol.

>  I have obzerved that nsupdate does not allow host names more than 62
>  chars long ( weird number ).

	Are you sure it's 62 characters and not 63?

>  Am I dealing with an nsupdate limit here or is it a DNS limit on
>  hostname lengths ?

	It's a DNS limit, and it cannot be changed (well, not without 
completely breaking the DNS, since no other nameservers on the planet 
will be able to deal with it).

-- 
Brad Knowles, <brad.knowles at skynet.be>

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