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Conference azur::mcc

Title:	DECmcc user notes file. Does not replace IPMT.
Notice:	Use IPMT for problems. Newsletter location in note 6187
Moderator:	TAEC::BEROUD

Created:	Mon Aug 21 1989
Last Modified:	Wed Jun 04 1997
Last Successful Update:	Fri Jun 06 1997
Number of topics:	6497
Total number of notes:	27359

1770.0. "Moving MCC to a new machine" by RDGENG::PRATT () Wed Nov 06 1991 09:10

Hi,

I currently have MCC running on a system with its own private DNS namespace.
For various reasons it is necessary to move MCC onto another system. What I
propose to do is to install MCC on the new system, use the existing DNS
namespace, run it up in parallel with the existing MCC until it has been
fully set up, and then delete the original MCC. 

However will I have problems having two separate MCC directors using the same
namespace, as the uids will be different between the 2 MIRs and DNS? Also would
this affect historian/exporter data? Would it be easier to install MCC on the
new system, and copy over the MIR files from the original system? Or will I not
have a problem in the first place?

Regards

Ian Pratt

T.R	Title	User	Personal Name	Date	Lines
1770.1	Grant access to 'new' MCC system.	TOOK::MCPHERSON	i'm only 5 foot one...	`Wed Nov 06 1991 10:25`	11
	I think the only problem you might have is that you need to remember to grant appropriate access rights to the _new_ MCC system (different DECnet address, correct?) on the DNS server running on the 'old' MCC system. If I understand your problem, that should cover you. Actually, the supposition made for using DNS as MCC's datastore is that multiple directors should share a single DNS server. After all, DNS is a pretty heavy burden to bear if you're not planning on _sharing_ the data, isn't it? /doug
1770.2	Are the UID's still valid?	RDGENG::PRATT		`Wed Nov 06 1991 14:36`	19
	Doug, That is what I was hoping to hear, but how is this problem resolved... If my understanding is correct, when you register an entity (eg node4) in MCC, then a uid is created for that entity, and is stored in both the MIR, and as an attribute of the object in DNS. A softlink is also created in the .MCC_UID directory which points the UID back to the object. All future references by MCC to that entity are done via the UID rather than the entity name (particularly the historian/exporter functions). If I register the same entity from my new Director will it use the existing UID attribute in DNS and put that into it's own MIR, or will it try to create a new one? If so, won't there be a conflict between the existing MIR and the new one? I recall having similiar problems in the early days of MCC, and I know that there are/were plans to change the way MCC uses UID's and DNS, have any changes been made? or is my understanding above totally incorrect? Ian
1770.3	Multiple users, multiple machines - no problem	TOOK::STRUTT	Management - the one word oxymoron	`Thu Nov 07 1991 21:14`	14
	The UIDs and the (no longer used) .MCC_UID namespace directory are both red herrings (ie. irrelevant). MCC was designed to allow multiple users on the same or separate machine to be able (subject to access controls, of course) to share the same namespace and hence be able to manage the same objects (again, subject to access controls). Having a single user or a single machine is only a special case of the more general case we implemented. If you find a situation (other than relating to access control) where it doesn't appear to work, please let us know. It certainly works for us! Colin