Mac OSX 10.5.3 Leopard STANDARD Server CHANGEIP questions

Question

I am confused on how to check and change TCP/IP addresses via Mac OSX Leopard 10.5.3 server in STANDARD mode.
I watched the great Sean Colins Lynda.com tutorial on OSX 10.5 Server, but i still have a few questions with how to deal with DNSs and CHANGE IP
Here is the hardware & scenario:
-- G5 Silver Doors Tower with 1.7GB Ram and Mac OSX 10.5 Leopard 10 user server
-- Cablevision ISP with there BOOST service [that allows you to set-up a server and does not block ports 25 or 80]
-- NO Static IP from Cablevison [they change it once in a blue moon when they want so I rely on DYNDNS below]
-- Apple Airport TimeCapsule [with all latest firmware updates etc]
-- DynDNS account and client software installed on server to update the DYNDNS severs with the current Cablevisions TCP/IP address
Problem and Question
===
Three times a year I will need to move this server. 1/3rd of year and at setup it is on residential Cablevision Account and Apple TimeCapsule Router, Then 2/3 of year server will be behind two funky large networks where I will have to set-up manual IP, DNS, and proxy info
I need to know what the proper process is when I want to move the Mac. When the 10.5.3 STANDARD Server is in STANDARD mode can I just change the TCP/IP address in SYSTEM PREFERENCES...NETWORK ? Do I have to run the CHANGEIP command Afterwards [or Before]
Also, for DNS config on server does it always need to have the loop back self reference [127.0.0.1] or can it just be configed from the Airport and/or network?
And, big problem for now... dumbly when I set-up the OSX Server on the TimeCapsule Network I forgot to write down the TCP/IP address used. Now I am on the second funky corporate network and can't use the command:
sudo changeip - idon't_knowip 10.0.96.48 server.cmtenyoffice.com server.cmtenyoffice.com
Also, another question for the HOSTNAME... should it be HOSTNAME or FullyQuallifiedDomainName?
My HOSTNAME seems to be "CMTE-Server.local" but I specified the FullyQualifiedDomainName to "sever.cmtenyoffice.com"
NOTE: I do NOT have this domain registered and am not yet hosting a website or email server on this machine, but I may soon register the domain and then point MX records etc to the DYNDNS record that would point to server
Anyhow, to wrap up,
1- What is the proper process for changing the TCP IP address with a Leopard 10.5.3 STANDARD SERVER?
2- What do I do with CHANGEIP command if I don't know what the STARTING TCP/IP address is?
3- For HOSTNAME should I be entering the unregistered FQDN or the "CMTE-Server.local"
Thanks for any an all info.
-- Eric ZORK Alan
-- Professional Poet & BED VLOGGER

Answer 1

Hi Eric
You use the one its using now.
If the Server is Standalone issue:
sudo changeip - oldIP newIP oldhostname newhostname
Even if nothing changes you can still issue the command, supply the system admin name and password and let it do its stuff. Prior to doing this you must change the address in the Network Preferences Pane. Although not necessary it does not hurt if you restart afterwards.
If the Server is an OD Master issue:
sudo changeip /LDAPv3/127.0.0.1 oldIP newIP oldhostname newhostname
You will not only be prompted for the system admin name and password but also for the Directory Administrator name and password. With both command you will get feedback as to what is going on. Obviously you will see more changes made if its an LDAP Server. Hostname will be the fully qualifed domain name (FQDN) defined in the DNS Service eg: myserver.mydomain.com.
man changeip
For usage. Actually prior to doing any of this and incidentally a good way of finding out not only the hostname but also the IP address associated with that name issue:
sudo changeip -checkhostname
You should run this before/after making the change. If everything checks out OK it should report 'the names match, there is nothing to change'. This is a good a test that lets you know its worked. However its not the only test. I would run host, nslookup and dig also. Next set a client to use the Server for its DNS and then test connectivity with firstly the Server's fqdn and lastly its IP Address.
Ultimately the truest test is: "what impact has the change made on clients accessing the Server and its Services successfully?"
If the Server is a mature OD Master (possibly PDC as well) with DNS, Mail, AFP, SMB, iCal and any other 2-3 additional services configured and running then issuing changeip may appear - superficially - to have worked. Occsasionally - in my experience - serious problems begin to develop with the LDAP database to the extent where the only 'cure' is to demote to Standalone, sorting out DNS and re-promoting. This can have serious repercussions if you have not made preparations to limit the re-build time prior to changing the IP address and issuing the command. Equally it can be successful. However can you take the risk?
Tony