topic Re: Hostname Maximum Character length in Operating System - HP-UX

Hostname Maximum Character length

Jagadesh — Thu, 06 Nov 2003 04:01:36 GMT

What is the default hostname character lenght in HP-UX 11 & 11i? How can i increase the same. What is the maximum value will it support?

Thanks
S.Jagadesh

Re: Hostname Maximum Character length

Robert-Jan Goossens — Thu, 06 Nov 2003 04:06:00 GMT

Hi Jagadesh,

http://www4.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000068695446

"uname -n" returns "unknown" DocId: UCMDSKBRC00012527 Updated: 5/28/03 11:22:00 AM

Regards,
Robert-Jan

Re: Hostname Maximum Character length

aparna challagulla — Thu, 06 Nov 2003 04:07:44 GMT

hi
The default is 8.
The maximum value is 64.
It is generally not advised to increase it from the default value due to some compatibility issues.
HTH
aparna

Re: Hostname Maximum Character length

G. Vrijhoeven — Thu, 06 Nov 2003 04:09:52 GMT

HI,

The name_of_host argument is restricted to
MAXHOSTNAMELEN characters as defined in .

Gideon

Re: Hostname Maximum Character length

Pete Randall — Thu, 06 Nov 2003 06:19:12 GMT

Personally, I can't imagine a reason good enough to convince me to exceed 8 characters. See the following threads:

http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0x2db614a24fd1d4118fef0090279cd0f9,00.html
and
http://forums.itrc.hp.com/cm/QuestionAnswer/1,,0xc2b7d5fab40ed6118ff40090279cd0f9,00.html

Pete

Re: Hostname Maximum Character length

Jagadesh — Thu, 06 Nov 2003 07:51:46 GMT

Thanks for the information.

What is the maximum lenght of Hostname. As the reply i come to know that is 64, but kindly clarify me whether is it 64 or 63.

Thanks
Jagadesh

Re: Hostname Maximum Character length

Pete Randall — Thu, 06 Nov 2003 08:02:35 GMT

Jagadesh,

Every reference I've seen says it's 64 characters but - I will repeat - I would NOT exceed 8 characters. You're asking for far more trouble than it's worth.

Pete

Re: Hostname Maximum Character length

Jagadesh — Thu, 06 Nov 2003 08:07:14 GMT

Hi Preet,

This hostname length qurey is for testing purpose only. We are not going to do this in the production environment. We need to exactly know what is the maximum character support for Hostname.

Thanks
Jagadesh

Re: Hostname Maximum Character length

Stuart Abramson_2 — Thu, 06 Nov 2003 09:39:25 GMT

I just went through this, and the question has been answered 100 times in the archives.

But, here's the answer:

You can go to a max of 64 characters, but DON'T EXCEED 8 CHARACTERS!

Here's why:

o...There is some important distinction between "hostname" and "nodename", which I have never understood.

o...Many HP-UX utilities, such as swinstall, for example, don't understand hostnames longer than 8 characters. So, if you:

.. swinstall -s longhostname:depot_name

he just plain won't be able to find it. And the error message won't much help you.

o...There are many other examples of this, which I can't remember. JUST DON'T EXCEED 8 CHARACTERS.

Re: Hostname Maximum Character length

rick jones — Thu, 06 Nov 2003 20:36:19 GMT

the "hostname" command returns the name of the system in the internet namespace

the "nodename" command returned the name of the system in the "ns transport/probe" namespace (stuff from the MPE systems)

the "uname" command returns the name of the system in the "uucp" namespace.

uname has an 8 character limit.
hostname has a 64 character limit
i forget about nodename, and it may have been usurped for the uname stuff - it may be "nodename" in the config files to set the uname name...

anyhow, i have set the "hostname" of my personal workstation (hp-ux 11) to "tardy.cup.hp.com" and the uname name to "tardy"

the wrinkles arise when you want the host part of the FQDN to be > 8 characters - some utilities/programs/scripts that really mean to be operating in the "internet" namespace are buggy and are using the uname command instead of the hostname command. if you do not have an "alias" in the uname space that maps to what you have in the internet space, this can be a problem.

it is not possible to increase the limit. it is hardcoded within the kernel/an include file.