Conference iosg::all-in-1_v30

    Hi,
    
    Given an entry in FILECAB we first get FILECAB.PARTITION, and we use
    this to determine if the drawer is local. If it is then we use
    FILECAB.UNIQUE_NAME as the key to the PARTITION, and get
    PARTITION.DIRECTORY as the drawer file location.
    
    We do not access PARTITION_MASTER in the local code, and this is only
    accessed by the FCS. So I'll defer to Bob on you second question.
    
    Cheers
    
    Stuart

    
    re .0
    
>2) Where can I found a description of the PARTITION_MASTER DSAB?? How is the link
>set betwwen PARTITION_MASTER and PARTITION.???
    
    The partition master file is keyed by the partition ID, which is a
    DNS$CTS of the partition object (the partition master file is only used
    at distribution level 1).
    
    When the server is handed a partition id to perform an action on it
    does the following:
    
    If this is the local server:
    	1) Do I service this partition? If the partition ID is in the
    	   partition master file then the server services it so it.
    	2) If I service the partition, lookup the name of the partition 
      	   definition file from the partition master file.
    	3) Use that partition file for the requested task.
        2a) If I don't service the partition (partition id is not in
            my partition master file), then the task must be brokered.
    	3a) Search the servers internal cache and/or DNS namespace to
            locate a server that does service the partition
     	4a) Broker the task to that server.
    
    If this is a server brokered TO:
    
    	1) Validate and authenticate the incoming connection request
    	   (from the server above at step 4a)
    	2) Verify that I really do service this partition by looking up
           the partition ID in my partition master file.
    	3) If I do service the partition, perform the requested task
    	4) If I don't service the partition return the error 
    	   OafcServerDnsNotSynch to indicate that this server
    	   and the DNS namespace are not in synch.
    
    some other info that may help you understand this all.
    
    When a server starts up at distribution level 1, it nexts through
    its partition master file, pulling partition names and IDs from 
    the file one by one. Each partition is then looked up in the DNS
    namespace to gather a server set for it and to verify that it exists
    and it is a partition. This info is then stored in a cache called the
    servers partition list. So in step 2 above, the file is not really
    used, the partition list is used to verify if the server services 
    the partition.
    
    the information in the DNS namespace and the infromation in a servers
    partition master file must match. That is to say, if the partition
    object in the DNS namespace says a server services a partiiton id, then
    that servers partition master file must have a partition id for that
    partition.
    
    --Bob
    

Re: .2

Bob,

I thought that the PARTITION_MASTER file contained one entry for each partition
on the cluster (assuming dist level 1) and that there was only one 
PARTITION_MASTER per cluster.

.2 implies that there is one PARTITION_MASTER per server.

Of course if all the servers in a cluster have to service the same set of 
partitions then both the above equate to the same thing.

Which one is right?

Thanks,

Terry

Re 2: What's DNS$CTS (I'm also ignorant about DNS)

And more in general, I got the Diamond FT slides aboit File cabinet Data structure
and the different Data strucures are layed out. But I can not find back 
explanation for different fileds (they do not appear in APR 1).
CAn yoy give me more info about the following fields

PARTITION.FORMAT
PARTITION.VERSION
PARTITION.DRAWER_IUID
PARTITION.MSG
PARTITION.FORWARD

FILECAB.EXTERNAL_UID

PARTITION_MASTER.OPAQUE_NAME

many thanks in advance

Pierre

    Re .4
    
    PARTITION.FORMAT	- not used in V3 - do not use it yourself
    PARTITION.VERSION	- not used in V3 - do not use it yourself
    PARTITION.DRAWER_IUID - internal identifier for use by File Cab. Server
    PARTITION.MSG	- flag whether drawer has [.MSG] subdirectory
    PARTITION.FORWARD	- not used in V3 - do not use it yourself
    
    FILECAB.EXTERNAL_UID - external identifier for use by File Cab. Server
    
    PARTITION_MASTER.OPAQUE_NAME - DNS internal representation of a
    				   partition name.
    
    Cheers
    
    Stuart

    
    re .3
    
    Terry,
          
    There is one partition master file per system and one partition file
    per partition (assuming distribution level 1). Distribution level
    0 partitions are not stored in the partition master file and there
    can be only 1 level 0 partition per system.
    
    A partition master file has an entry in it for each partition on the
    system.  there can be multiple servers per partition, but each server
    needs its own server configuration file.
    

    that clear it up??
    
    --Bob
    

Bob,

So that means all the servers in a cluster service the same set of 
partitions. Right?

Terry

    
    Terry,
    
    Yup, there are ways around that, but I don't believe we document them.
    
    --Bob