Conference azur::mcc

6160.0. "Domain lookups very slow" by DV780::SMITHG () Fri Nov 04 1994 18:46

My customer is running MCC 1.3, VMS 5.5-2 and DNS 2.0.  The MCC 
domain structure and DNS directories are defined as below.  What's going on
is that when they click on certain domains within MCC it takes forever to 
complete the "look into" -  basically to open up the domain and display it
on the screen.  The worst example of this is when opening domain 
United_States; we've clocked 18 minutes on the 4500 and 12 minutes on an
alpha we're using for test.  I am trying to help the customer figure out if
the problem in with DNS or MCC.

    (most of the network entities are DECnis routers and are accessed
    via the DECnet/OSI AM; 50 of so of them.)
    
I'm not at all familiar with how DNS does it's lookups and wondered about 
the possibility that the dictionary structure is defined as well as it
could be.  I'm particularly concerned about the huge flat structure that
they use for XYZ.MCC.  Does DNS index thru something like that or is it
a sequential path that's taken?

    BTW: the DNS server is not on the same machine that's running MCC. 
    I've also looked thru the older notes that addressed DNS performance
    and they appear to have been resolved in earlier releases of MCC or
    DNS.

Any help you can give me on this would be great.

Thanks, Gary

   

MCC Domain Structure:
                                                      
				XYZnet
				  |
	--------------------------+--------------------------------
	|		|		|		| ...
     Canada	  United_States	      XYZwan*
			|
	   -------------+--------------
	   |	 |	|	| ...
	  AZ	CA	CO		       *Note:  The only entities 
			|			defined in domain XYZwan
	       ---------+---------		are the domains for the
	       |	|	|...		network cabs (CSPPOP_1, etc)
	     DENV      CSP
		        |
	       ---------+--------
	       |	|	|...
	   CSPPOP_1 CSPPOP_2			<- Lowest level domain defined
			|			   These are the network cabs
		--------+----------		   in each city
		|	|	|...
	    CSP001   CSP002   CSP300		<- Network devices in the cab
						   such as routers, servers,
						   concentrators


DNS Directory Strucure:

				XYZ:.
				 |
	      -------------------------------------------
	      |						|
	     MCC.				       USA.
	      |						|
	------+--------------------------------		|
	|	|	|	|	|...		|
 United_States CO    XYZnet  CSPPOP_1 DENV 		|
(No further levels defined here; everything      	|
 except the individual network devices are		|
 defined here... one long horizontal structure)		|
							|
							|
		              --------------------------+
			      |
	 	-------------------------------
		|	|	|	|...
	       DEN     CSP     SCR     ZNR	<- city codes
		        |
	     	--------+-----------
		|	|	|...
	     CSP001   CSP002 CSP300    		<- this is where all the
						   individual network devices
						   are defined, such as
						   routers, concentrators,
				   	           servers, etc.
							

            <<< NOTED::DISK$NOTES8:[NOTES$LIBRARY_8OF4]DNS.NOTE;3 >>>
                -< DECdns - Digital's Distributed Name Service >-
================================================================================
Note 1188.2            18+ minutes to look into MCC domain                2 of 2
DV780::SMITHG                                        18 lines  15-NOV-1994 16:51
                          -< additional information >-
--------------------------------------------------------------------------------
    I have a little more information to add on the configuration and the
    testing that we have done:
    
    - first, MCC was running in medium confidence not low.  We have defined
    the MCC_DNS_CONF logical to low and it made a big difference!  The area
    that still needs improvement is when looking into an MCC domain that
    contains mainly DECnet/OSI nodes (DECnis routers in our case.)
    
    - the DNS directories are defined in a single clearinghouse.  That will
    change shortly when the customer puts a replica of the root directory
    on another machine.
    
    - We have not yet been able to do the clerk traces.
    
    What would help me the most right now, are comments on the customer's
    DNS directory structure.  Does it look reasonable?  
    
    Thanks again.  Gary